Web Standards

Let’s suppose you have N elements with the same animation that should animate sequentially. The first one, then the second one, and so on until we reach the last one, then we loop back to the beginning. I am sure you know what I am talking about, and you also know that it’s tricky to get such an effect. You need to define complex keyframes, calculate delays, make it work for a specific number of items, etc.

Tell you what: with modern CSS, we can easily achieve this using a few lines of code, and it works for any number of items!

The following demo is currently limited to Chrome and Edge, but will work in other browsers as the sibling-index() and sibling-count() functions gain broader support. You can track Firefox support in Ticket #1953973 and WebKit’s position in Issue #471.

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In the above demo, the elements are animated sequentially and the keyframes are as simple as a single to frame changing an element’s background color and scale:

@keyframes x { to { background: #F8CA00; scale: .8; } }

You can add or remove as many items as you want and everything will keep running smoothly. Cool, right? That effect is made possible with this strange and complex-looking code:

.container > * { --_s: calc(100%*(sibling-index() - 1)/sibling-count()); --_e: calc(100%*(sibling-index())/sibling-count()); animation: x calc(var(--d)*sibling-count()) infinite linear(0, 0 var(--_s), 1, 0 var(--_e), 0); }

It’s a bit scary and unreadable, but I will dissect it with you to understand the logic behind it.

The CSS linear() function

When working with animations, we can define timing functions (also called easing functions). We can use predefined keyword values — such as linear, ease, ease-in, etc. — or steps() to define discrete animations. There’s also cubic-bezier().

But we have a newer, more powerful function we can add to that list: linear().

From the specification:

A linear easing function is an easing function that interpolates linearly between its control points. Each control point is a pair of numbers, associating an input progress value to an output progress value.

animation-timing-function: linear creates a linear interpolation between two points — the start and end of the animation — while the linear() function allows us to define as many points as we want and have a “linear” interpolation between two consecutive points.

It’s a bit confusing at first glance, but once we start working with it, things becomes clearer. Let’s start with the first value, which is nothing but an equivalent of the linear value.

linear(0 0%, 1 100%)

We have two points, and each point is defined with two values (the “output” progress and “input” progress). The “output” progress is the animation (i.e., what is defined within the keyframes) and the “input” progress is the time.

Let’s consider the following code:

.box { animation: move 2s linear(0 0%, 1 100%); } @keyframes move { 0% {translate: 0px } 100% {translate: 80px} }

In this case, we want 0 of the animation (translate: 0px) at t=0% (in other words, 0% of 2s, so 0s) and 1 of the animation (translate: 80px) at t=100% (which is 100% of 2s, so 2s). Between these points, we do a linear interpolation.

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Instead of percentages, we can use numbers, which means that the following is also valid:

linear(0 0, 1 1)

But I recommend you stick to the percentage notation to avoid getting confused with the first value which is a number as well. The 0% and 100% are implicit, so we can remove them and simply use the following:

linear(0, 1)

Let’s add a third point:

linear(0, 1, 0)

As you can see, I am not defining any “input” progress (the percentage values that represent the time) because they are not mandatory; however, introducing them is the first thing to do to understand what the function is doing.

The first value is always at 0% and the last value is always at 100%.

linear(0 0%, 1, 0 100%)

The value will be 50% for the middle point. When a control point is missing its “input” progress, we take the mid-value between two adjacent points. If you are familiar with gradients, you will notice the same logic applies to color stops.

linear(0 0%, 1 50%, 0 100%)

Easier to read, right? Can you explain what it does? Take a few minutes to think about it before continuing.

Got it? I am sure you did!

It breaks down like this:

1. We start with translate: 0px at t=0s (0% of 2s).
2. Then we move to translate: 80px at t=1s (50% of 2s).
3. Then we get back to translate: 0px at t=2s (100% of 2s).

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Most of the timing functions allow us to only move forward, but with linear() we can move in both directions as many times as we want. That’s what makes this function so powerful. With a “simple” keyframes you can have a “complex” animation.

I could have used the following keyframes to do the same thing:

@keyframes move { 0%, 100% { translate: 0px } 50% { translate: 80px } }

However, I won’t be able to update the percentage values on the fly if I want a different animation. There is no way to control keyframes using CSS so I need to define new keyframes each time I need a new animation. But with linear(), I only need one keyframes.

In the demo below, all the elements are using the same keyframes and yet have completely different animations!

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Now that we know more about linear(), let’s move to the main trick of our effect. Don’t forget that the idea is to create a sequential animation with a certain number (N) of elements. Each element needs to animate, then “wait” until all the others are done with their animation to start again. That waiting time can be seen as a delay.

The intuitive way to do this is the following:

@keyframes move { 0%, 50% { translate: 0px } 100% { translate: 80px } }

We specify the same value at 0% and 50%; hence nothing will happen between 0% and 50%. We have our delay, but as I said previously, we won’t be able to control those percentages using CSS. Instead, we can express the same thing using linear():

linear(0 0%, 0 50%, 1 100%)

The first two control points have the same “output” progress. The first one is at 0% of the time, and the second one at 50% of the time, so nothing will “visually” happen in the first half of the animation. We created a delay without having to update the keyframes!

@keyframes move { 0% { translate: 0px } 100% { translate: 80px } } CodePen Embed Fallback

Let’s add another point to get back to the initial state:

linear(0 0%, 0 50%, 1 75%, 0 100%)

Or simply:

linear(0, 0 50%, 1, 0) CodePen Embed Fallback

Cool, right? We’re able to create a complex animation with a simple set of keyframes. Not only that, but we can easily adjust the configuration by tweaking the linear() function. This is what we will do for each element to get our sequential animation!

The full animation

Let’s get back to our first animation and use the previous linear() value we did before. We will start with two elements.

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Nothing surprising yet. Both elements have the exact same animation, so they animate the same way at the same time. Now, let’s update the linear() function for the first element to have the opposite effect: an animation in the first half, then a delay in the second half.

linear(0, 1, 0 50%, 0)

This literally inverts the previous value:

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Tada! We have established a sequential animation with two elements! Are you starting to see the idea? The goal is to do the same with any number (N) of elements. Of course, we are not going to assign a different linear() value for each element — we will do it programmatically.

First, let’s draw a figure to understand what we did for two elements.

When one element is waiting, the other one is animating. We can identify two ranges. Let’s imagine the same with three elements.

This time, we need three ranges. Each element animates in one range and waits in two ranges. Do you see the pattern? For N elements, we need N ranges, and the linear() function will have the following syntax:

linear(0, 0 S, 1, 0 E, 0)

The start and the end are equal to 0, which is the initial state of the animation, then we have an animation between S and E. An element will wait from 0% to S, animate from S to E, then wait again from E to 100%. The animation time equals to 100%/N, which means E - S = 100%/N.

The first element starts its animation at the first range (0 * 100%/N), the second element at the second range (1 * 100%/N), the third element at the third range (2 * 100%/N), and so on. S is equal to:

S = (i - 1) * 100%/N

…where i is the index of the element.

Now, you may ask, how do we get the value of N and i? The answer is as simple as using the sibling-count()and sibling-index() functions! Again, these are currently supported in Chromium browsers, but we can expect them to roll out in other browsers down the road.

S = calc(100%*(sibling-index() - 1)/sibling-count())

And:

E = S + 100%/N E = calc(100%*sibling-index()/sibling-count())

We write all this with some good CSS and we are done!

.box { --d: .5s; /* animation duration */ --_s: calc(100%*(sibling-index() - 1)/sibling-count()); --_e: calc(100%*(sibling-index())/sibling-count()); animation: x calc(var(--d)*sibling-count()) infinite linear(0, 0 var(--_s), 1, 0 var(--_e), 0); } @keyframes x { to { background: #F8CA00; scale: .8; } }

I used a variable (--d) to control the duration, but it’s not mandatory. I wanted to be able to control the amount of time each element takes to animate. That’s why I multiply it later by N.

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Now all that’s left is to define your animation. Add as many elements as you want, and watch the result. No more complex keyframes and magic values!

Note: For unknown reasons (probably a bug) you need to register the variables with @property.

More variations

We can extend the basic idea to create more variations. For example, instead of having to wait for an element to completely end its animation, the next one can already start its own.

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This time, I am defining N + 1 ranges, and each element animates in two ranges. The first element will animate in the first and second range, while the second element will animate in the second and third range; hence an overlap of both animations in the second range, etc.

I will not spend too much time explaining this case because it’s one example among many we create, so I let you dissect the code as a small exercise. And here is another one for you to study as well.

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The linear() function was mainly introduced to create complex easing such as bounce and elastic, but combined with other modern features, it unlocks a lot of possibilities. Through this article, we got a small overview of its potential. I said “small” because we can go further and create even more complex animations, so stay tuned for more articles to come!

Sequential linear() Animation With N Elements originally published on CSS-Tricks, which is part of the DigitalOcean family. You should get the newsletter.

Last week I had a running list of user experience and technical hurdles that made using applications "within" AI models challenging. Then OpenAI's ChatGPT Apps announcement promised to remove most of them. Given how much AI is changing how apps are built and used, I thought it would be worth talking through these challenges and OpenAI's proposed solutions.

Whether you call it a chat app, a remote MCP server app, or an embedded app, when your AI application runs in ChatGPT, the capabilities of ChatGPT become capabilities of your app. ChatGPT can search the web, so can your app. ChatGPT can connect to Salesforce, so can your app. These all sound like great reasons to build an embedded AI app but... there's tradeoffs.

Embedded apps previously had to be added to Claude.ai or ChatGPT (in developer mode) by connecting a remote MCP server, for which the input field could be several clicks deep into a client's settings. That process turned app discovery into a brick wall for most people.

To address this, OpenAI announced a formal app submission and review process with quality standards. Yes, an app store. Get approved and installing your embedded app becomes a one-click action (pending privacy consent flows). No more manual server configs.

If you were able to add an embedded app to a chat client like Claude.ai or ChatGPT, using it was a mostly text-based affair. Embedded apps could not render images much less so, user interface controls. So people were left reading and typing.

Now, ChatGPT apps are able to render "React components that run inside an iframe" which not only enables inline images, maps, and videos but custom user interface controls as well. These iframes can also run in an expanded full screen mode giving apps more surface area for app-specific UI and in a picture-in-picture (PIP) mode for ongoing sessions.

This doesn't mean that embedded app discoverability problems are solved. People still need to either ask for apps by name in ChatGPT, access them by through the "+" button, or rely on the model's ability to decide if/when to use specific apps.

The back and forth between the server running an embedded app and the AI client also has room for improvement. Unlike desktop and mobile operating systems, ChatGPT doesn't (yet) support automatic background refresh, server-initiated notifications, or even passing files (only context) from the front end to a server. These capabilities are pretty fundamental to modern apps, so perhaps support isn't far away.

The tradeoffs involved in building apps for any platform have always been about distribution and technical capabilities or limitations. 800M weekly ChatGPT users is a compelling distribution opportunity and with ChatGPT Apps, a lot of embedded AI app user experience and technical issues have been addressed.

Is this enough to move MCP remote servers from a developer-only protocol to applications that feel like proper software? It's the same pattern from every platform shift: underlying technology first, then the user experience layer that makes it accessible. And there was definitely big steps forward on that last week.

You’ve probably heard the buzz about CSS Masonry. You might even be current on the ongoing debate about how it should be built, with two big proposals on the table, one from the Chrome team and one from the WebKit team.

The two competing proposals are interesting in their own right. Chrome posted about its implementation a while back, and WebKit followed it up with a detailed post stating their position (which evolved out of a third proposal from the Technical Architecture Group).

We’ll rehash some of that in this post, but even more interesting to me is that this entire process is an excellent illustration of how the CSS Working Group (CSSWG), browsers, and developers coalesce around standards for CSS features. There are tons of considerations that go into a feature, like technical implementations and backwards compatibility. But it can be a bit political, too.

That’s really what I want to do here: look at the CSS Masonry discussions and what they can teach us about the development of new CSS features. What is the CSSWG’s role? What influence do browsers have? What can learn from the way past features evolved?

Masonry Recap

A masonry layout is different than, say Flexbox and Grid, stacking unevenly-sized items along a single track that automatically wraps into multiple rows or columns, depending on the direction. It’s called the “Pinterest layout” for the obvious reason that it’s the hallmark of Pinterest’s feed.

Pinterest’s masonry layout

We could go deeper here, but talking specifically about CSS Masonry isn’t the point. When Masonry entered CSS Working Group discussions, the first prototype actually came from Firefox back in 2019, based on an early draft that integrated masonry behavior directly into Grid.

The Chrome team followed later with a new display: masonry value, treating it as a distinct layout model. They argued that masonry is a different enough layout from Flexbox and Grid to deserve its own display value. Grid’s defaults don’t line up with how masonry works, so why force developers to learn a bunch of extra Grid syntax? Chrome pushed ahead with this idea and prototyped it in Chrome 140:

.container { display: masonry; grid-template-columns: repeat(auto-fit, minmax(160px, 1fr)); gap: 10px; }

Meanwhile, the WebKit team has proposed that masonry should be a subset of Grid, rather than its own display type. They endorsed a newer direction based on a recommendation by the W3C Technical Architecture Group (TAG) built around a concept called Item Flow that unifies flex-flow and grid-auto-flow into a single set of properties. Instead of writing display: masonry, you’d stick with display: grid and use a new item-flow shorthand to collapse rows or columns into a masonry-style layout:

.container { display: grid; grid-template-columns: repeat(auto-fill, minmax(14rem, 1fr)); item-flow: row collapse; gap: 1rem; }

The debate here really comes down to mental models and how you think about masonry. WebKit sees it as a natural extension of Grid, not a brand-new system. Their thinking is that developers shouldn’t need to learn an entirely new model when most of it already exists in Grid. With item-flow, you’re not telling the browser “this is a whole new layout system,” you’re more or less adjusting the way elements flow in a particular context.

How CSS Features Evolve

This sort of horse-trading isn’t new. Both Flexbox and Grid went through years of competing drafts before becoming the specs we use today. Flexbox, in particular, had a rocky rollout in the early 2010s. Those who were in the trenches at the time likely remember multiple conflicting syntaxes floating around at once. The initial release had missing gaps and browsers implemented the features differently, leading to all kinds of things, like proprietary properties, experimental releases, and different naming conventions that made the learning curve rather steep, and even Frankenstein-like usage in some cases to get the most browser support.

In other words, Flexbox (nor Grid, for that matter) did not enjoyed a seamless release, but we’ve gotten to a place where the browsers implementations are interoperable with one another. That’s a big deal for developers like us who often juggle inconsistent support for various features. Heck, Rob O’Leary recently published the rabbit hole he traveled trying to use text-wrap: pretty in his work, and that’s considered “Baseline” support that is “widely available.”

But I digress. It’s worth noting that Flexbox faced unique challenges early on, and masonry has benefitted from those lessons learned. I reached out to CSSWG member Tab Atkins-Bittner for a little context since they were heavily involved in editing the Flexbox specification.

“Flexbox was the first of the modern layout algorithms; we made a lot of mistakes and missteps while writing it, because we were trying to figure out how a modern layout model should work.”

In other words, Flexbox was sort of a canary in the coal mine as the CSSWG considered what a modern CSS layout syntax should accomplish. This greatly benefited the work put into defining CSS Grid because a lot of the foundation for things like tracks, intrinsic sizing, and proportions were already tackled. Atkins-Bittner goes on further to explain that the Grid specification process also forced the CSSWG to rethink several of Flexbox’s design choices in the process.

“We found a lot of decisions that made sense on their own in Flexbox needed to be changed if we wanted them to apply more generally.”

This also explains why Flexbox underwent several revisions following its initial release.

It also highlights another key point: CSS features are always evolving. Early debate and iteration are essential because they reduce the need for big breaking changes. Still, some of the Flexbox mistakes (which do happen) became widely adopted. Browsers had widely implemented their approaches and the specification caught up to it while trying to establish a consistent language that helps both user agents and developers implemented and use the features, respectively.

All this to say: Masonry is in a much better spot than Flexbox was at its inception. It benefits from the 15+ years that the CSSWG, browsers, and developers contributed to Flexbox and Grid over that time. The discussions are now less about fixing under-specified details and more about high-level design choices. Hence, novel ideas born from Masonry that combine the features of Flexbox and Grid into the new Item Flow proposal.

It’s messy. And weird. But it’s how things get done.

The CSSWG’s Role

Getting to this point requires process. And in CSS, that process runs through the Working Group. The CSS Working Group (CSSWG) runs on consensus: members debate in the open, weigh pros and cons, and push browsers towards common ground.

Miriam Suzanne, an invited expert with the CSSWG (and CSS-Tricks alumni), describes the process like this:

“The group runs on a consensus model, so everyone has to eventually come to an agreement — or at least agree not to block the most popular path forward.”

But consensus only applies to the specifications. Browsers still decide when and how to those features are shipped, as Suzanne continues:

“Browsers make their own decisions about how strictly they follow a spec, and sometimes release features that haven’t been fully specified. That can lead to situations where the group decides to change a spec years later to match what browsers actually implemented.”

So, while the CSSWG facilitates discussions around features, it can’t actually stop browsers from shipping those features, let alone how they’re implemented. It’s a consensus-driven system, but consensus is only about publishing a specification. In practice, momentum can shift if one vendor is the first to ship or prototype a feature.

In most cases, though, the specification adoption process results in a stronger proposal overall. By the time features ship, the idea is that they’ve already been thoroughly debated, which in theory, reduces the need for significant revisions later that could lead to breaking changes. Backwards compatibility is always at the forefront of CSSWG discussions.

Developer feedback also plays an important role, though there isn’t a single standardized way that it is solicited, collected, or used. For the CSSWG, the csswg-drafts GitHub repo is the primary source of feedback and discussion, while browsers also run their own surveys and gather input through various other channels such as Chrome’s technical discussion groups and Webkit’s mailing lists.

The Bigger Picture

Browsers are in the business of shaping new features. It’s also in their best interest for a number of reasons. Proposing new ideas gives them a seat at the table. Prototyping new features gets developers excited and helps further refine edge cases. Implementing new features (particularly first) gives them a competitive edge in the consumer market.

All that said, prototyping features ahead of consensus is a bit of a tightrope walk.

And that’s where Masonry comes back into the bigger picture. Chrome shipped a prototype of the feature that leans heavily into the first proposal for a new display: masonry value. Other browsers have yet to ship competing prototypes, but have openly discussed their positions, as WebKit did in subsequent blog posts.

At first glance, that might suggest that Chrome is taking a heavy-handed approach to tip the scales in its favorable direction. But there’s a lot to like about prototyping features because it’s proof in the pudding for real-world uses by allowing developers early access to experiment.

Atkins-Bittner explains it nicely:

“Prototyping before consensus is an important part of building consensus. You get early implementation feedback, you get more eyes on the problem (the implementing engineers rather than just the spec authors).”

This kind of “soft” commit moves conversations forward while leaving room to change course, if needed, based on real-world use.

But there’s obviously a tension here as well. Browsers may be custodians of web standards and features, but they’re still employed by massive companies that are selling a product at the end of the day. It’s easy to get cynical. And political.

In theory, though, allowing browsers to voluntarily adopt features gives everyone choice: browsers compete in the market based on what they implement, developers gain new features that push the web further, and everyone gets to choose the browser that best fits their browsing needs.

If one company controls access to a huge share of users, however, those choices feel less accessible. Standards often get shaped just as much by market power as by technical merit.

Where We’re At

At the end of the day, standards get shaped by a mix of politics, technical trade-offs, and developer feedback. Consensus is messy, and it’s rarely about one side “winning.” With masonry, it might look like Google got its way, but in reality the outcome reflects input from both proposals, plus ideas from the wider community.

As of this writing:

• Masonry will be a new display type, but must include the word “grid” in the name. The exact keyword is still being debated.
• The CSSWG has resolved to proceed with the proposed **item-flow** approach.
• Grid will be used for layout templates and explicitly placing items in them.
• Some details, like a possible shorthand syntax and track listing defaults, are still being discussed.

Further reading

This is a big topic, one that goes much deeper and further than we’ve gone here. While working on this article, a few others popped up that are very much worth your time to see the spectrum of ideas and opinions about the CSS standards process:

• Alex Russell’s post about the standards adoption process in browsers.
• Rob O’Leary’s article about struggling with text-wrap: pretty, explaining that “Baseline” doesn’t always mean consistent support in practice.
• David Bushell’s piece about the WHATWG. It isn’t about the CSSWG specifically, but covers similar discussions on browser politics and standards consensus.

Masonry: Watching a CSS Feature Evolve originally published on CSS-Tricks, which is part of the DigitalOcean family. You should get the newsletter.

The stretch keyword, which you can use with width and height (as well as min-width, max-width, min-height, and max-height, of course), was shipped in Chromium web browsers back in June 2025. But the value is actually a unification of the non-standard -webkit-fill-available and -moz-available values, the latter of which has been available to use in Firefox since 2008.

The issue was that, before the @supports at-rule, there was no nice way to implement the right value for the right web browser, and I suppose we just forgot about it after that until, whoops, one day I see Dave Rupert casually put it out there on Bluesky a month ago:

Layout pro Miriam Suzanne recorded an explainer shortly thereafter. It’s worth giving this value a closer look.

What does stretch do?

The quick answer is that stretch does the same thing as declaring 100%, but ignores padding when looking at the available space. In short, if you’ve ever wanted 100% to actually mean 100% (when using padding), stretch is what you’re looking for:

div { padding: 3rem 50vw 3rem 1rem; width: 100%; /* 100% + 50vw + 1rem, causing overflow */ width: stretch; /* 100% including padding, no overflow */ } CodePen Embed Fallback

The more technical answer is that the stretch value sets the width or height of the element’s margin box (rather than the box determined by box-sizing) to match the width/height of its containing block.

Note: It’s never a bad idea to revisit the CSS Box Model for a refresher on different box sizings.

And on that note — yes — we can achieve the same result by declaring box-sizing: border-box, something that many of us do, as a CSS reset in fact.

*, ::before, ::after { box-sizing: border-box; }

I suppose that it’s because of this solution that we forgot all about the non-standard values and didn’t pay any attention to stretch when it shipped, but I actually rather like stretch and don’t touch box-sizing at all now.

Yay stretch, nay box-sizing

There isn’t an especially compelling reason to switch to stretch, but there are several small ones. Firstly, the Universal selector (*) doesn’t apply to pseudo-elements, which is why the CSS reset typically includes ::before and ::after, and not only are there way more pseudo-elements than we might think, but the rise in declarative HTML components means that we’ll be seeing more of them. Do you really want to maintain something like the following?

*, ::after, ::backdrop, ::before, ::column, ::checkmark, ::cue (and ::cue()), ::details-content, ::file-selector-button, ::first-letter, ::first-line, ::grammar-error, ::highlight(), ::marker, ::part(), ::picker(), ::picker-icon, ::placeholder, ::scroll-button(), ::scroll-marker, ::scroll-marker-group, ::selection, ::slotted(), ::spelling-error, ::target-text, ::view-transition, ::view-transition-image-pair(), ::view-transition-group(), ::view-transition-new(), ::view-transition-old() { box-sizing: border-box; }

Okay, I’m being dramatic. Or maybe I’m not? I don’t know. I’ve actually used quite a few of these and having to maintain a list like this sounds dreadful, although I’ve certainly seen crazier CSS resets. Besides, you might want 100% to exclude padding, and if you’re a fussy coder like me you won’t enjoy un-resetting CSS resets.

Animating to and from stretch

Opinions aside, there’s one thing that box-sizing certainly isn’t and that’s animatable. If you didn’t catch it the first time, we do transition to and from 100% and stretch:

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Because stretch is a keyword though, you’ll need to interpolate its size, and you can only do that by declaring interpolate-size: allow-keywords (on the :root if you want to activate interpolation globally):

:root { /* Activate interpolation */ interpolate-size: allow-keywords; } div { width: 100%; transition: 300ms; &:hover { width: stretch; } }

The calc-size() function wouldn’t be useful here due to the web browser support of stretch and the fact that calc-size() doesn’t support its non-standard alternatives. In the future though, you’ll be able to use width: calc-size(stretch, size) in the example above to interpolate just that specific width.

Web browser support

Web browser support is limited to Chromium browsers for now:

• Opera 122+
• Chrome and Edge 138+ (140+ on Android)

Luckily though, because we have those non-standard values, we can use the @supports at-rule to implement the right value for the right browser. The best way to do that (and strip away the @supports logic later) is to save the right value as a custom property:

:root { /* Firefox */ @supports (width: -moz-available) { --stretch: -moz-available; } /* Safari */ @supports (width: -webkit-fill-available) { --stretch: -webkit-fill-available; } /* Chromium */ @supports (width: stretch) { --stretch: stretch; } } div { width: var(--stretch); }

Then later, once stretch is widely supported, switch to:

div { width: stretch; } In a nutshell

While this might not exactly win Feature of the Year awards (I haven’t heard a whisper about it), quality-of-life improvements like this are some of my favorite features. If you’d rather use box-sizing: border-box, that’s totally fine — it works really well. Either way, more ways to write and organize code is never a bad thing, especially if certain ways don’t align with your mental model.

Plus, using a brand new feature in production is just too tempting to resist. Irrational, but tempting and satisfying!

We Completely Missed width/height: stretch originally published on CSS-Tricks, which is part of the DigitalOcean family. You should get the newsletter.

Anyone that's designed software has likely had to address the "empty state" problem. While an application can create useful stuff, getting users over the initial hurdle of creation is hard. With today's technology, however, AI models can cross the creation chasm so people don't have.

If you're designing a spreadsheet application, you'll need a "new spreadsheet" page. If you're designing a presentation tool, you'll need an empty state for new presentations. Document editors, design tools, project management apps... they all face the same hurdle: how do you help people get started when they're staring at a blank canvas?

Designers have tried to address the creation chasm many times resulting in a bunch of common patterns you'll encounter in any software app you use.

• Coach marks that educate people on what they can change and how
• Templates that provide pre-built starting points
• Tours that walk users through key features
• Overlays that highlight important interface elements
• Videos that demonstrate how to use an application

These approaches require people to learn first, then act. But in reality most of us just jump right into doing and only fall-back on learning if what we try doesn't work. Shockingly, asking people to read the manual first doesn't work.

But with the current capabilities of AI models, we can do something different. AI can model how to use a product by actually going through the process of creating something and letting people watch. From there, people can just tweak the result to get closer to what they want. AI does the creation, people do the curation.

Rather than learning then doing, people observe then refine. Instead of starting from nothing, they start from something an AI builds for them and making it their own. Instead of teaching people how to create, we show them creation in action. In other words, the AI does the (onboarding) work.

You can see this in action on ChatDB which allows people to instantly understand, visualize, and share data. When you upload a set of data to ChatDB it, will:

• make a dashboard for you
• name your dashboard
• write a description for it
• pick an icon and color set for it
• make you a series of initial charts
• pin one to your dashboard

All this happens in front of your eyes making it clear how ChatDB works and what you can do with it, no onboarding required.

Once your dashboard is made, it's trivial to edit the title (just click and type), change the icon, colors, and more. AI gives you the starting point and you take it from there. Try it out yourself.

With this approach, we can shift from applications that tell people how to use them to applications that show people what they can do by doing it for them. The traditional empty state problem transforms from "how do we help people start?" to "how do we help people refine?" And software shows people what's possible through action rather than instruction.

One of our favorites, Andy Clarke, on the one thing keeping the CSS contrast-color() function from true glory:

For my website design, I chose a dark blue background colour (#212E45) and light text (#d3d5da). This colour is off-white to soften the contrast between background and foreground colours, while maintaining a decent level for accessibility considerations.

But here’s the thing. The contrast-color() function chooses either white for dark backgrounds or black for light ones. At least to my eyes, that contrast is too high and makes reading less comfortable, at least for me.

Word. White and black are two very safe colors to create contrast with another color value. But the amount of contrast between a solid white/black and any other color, while offering the most contrast, may not be the best contrast ratio overall.

This was true when added a dark color scheme to my personal website. The contrast between the background color, a dark blue (hsl(238.2 53.1% 12.5%), and solid white (#fff) was too jarring for me.

To tone that down, I’d want something a little less opaque than what, say hsl(100 100% 100% / .8), or 20% lighter than white. Can’t do that with contrast-color(), though. That’s why I reach for light-dark() instead:

body { color: light-dark(hsl(238.2 53.1% 12.5%), hsl(100 100% 100% / .8)); }

Will contrast-color() support more than a black/white duo in the future? The spec says yes:

Future versions of this specification are expected to introduce more control over both the contrast algorithm(s) used, the use cases, as well as the returned color.

I’m sure it’s one of those things that ‘s easier said than done, as the “right” amount of contrast is more nuanced than simply saying it’s a ratio of 4.5:1. There are user preferences to take into account, too. And then it gets into weeds of work being done on WCAG 3.0, which Danny does a nice job summarizing in a recent article detailing the shortcomings of contrast-color().

The thing about contrast-color originally published on CSS-Tricks, which is part of the DigitalOcean family. You should get the newsletter.

As we saw during the PC, Web, and mobile technology shifts, how software applications are built, used, and distributed will change with AI. Most AI applications built to date have adopted a wrapper approach but increasingly, being embedded is becoming a viable option too. So let's look at both...

Wrapper AI Apps

Wrapper apps build a custom software experience around an AI model(s). Think of these as traditional applications that use AI as their primary processing engine for most core tasks. These apps have a familiar user interface but their features use one or more AI models for processing user input, information retrieval, generating output, and more. With wrapper apps, you need to build the application's input and output capabilities, integrations, user interface, and how all these pieces and parts work with AI models.

The upside is you can make whatever interface you want, tailored to your specific users' needs and continually improve it through your visibility of all user interactions. The cost is you need to build and maintain the ever-increasing list of capabilities users expect with AI applications like: the ability to use image understanding as input, the ability to search the Web, the ability to create PDFs or Word docs, and much more.

Embedded AI Apps

Embedded AI apps operate within existing AI clients like Claude.ai or ChatGPT. Rather than building a standalone experience, these apps leverage the host client for input, output, and tool capabilities, alongside a constantly growing list of integrations.

To use concrete examples, if ChatGPT lets people to turn their conversation results into a podcast, your app's results can be turned into a podcast. With a wrapper app, you'd be building that capability yourself. Similarly, if Claude.ai has an integration with Google Drive, your app running in Claude.ai has an integration with Google Drive, no need for you to build it. If ChatGPT can do deep research, your app can ... you get the idea.

So what's the price? For starters, your app's interface is limited by what the client you're operating in allows. ChatGPT Apps, for instance, have a set of design guidelines and developer requirements not unlike those found in other app stores. This also means how your app can be found and used is managed by the client you operate in. And since the client manages context throughout any task that involves your app, you lose the ability to see and use that context to improve your product.

Doing Both

Like the choice between native mobile apps and mobile Webs sites during the mobile era... you can do both. Native mobile apps are great for rich interactions and the mobile Web is great for reach. Most software apps benefit from both. Likewise, an AI application can work both ways. ChatDB illustrates this and the trade-offs involved. ChatDB is a service that allows people to easily make chat dashboards from sets of data.

People can use ChatDB as a standalone wrapper app or embedded within their favorite AI client like Claude or ChatGPT (as illustrated in the two embedded videos). The ChatDB wrapper app allows people to make charts, pin them to a dashboard, rearrange them and more. It's a UI and product experience focused solely on making awesome dashboards and sharing them.

The embedded ChatDB experience allows people make use of tools like Search and Browse or integrations with data sources like Linear to find new data and add it to their dashboards. These capabilities don't exist in the ChatDB wrapper app and maybe never will because of the time required to build and maintain them. But they do exist in Claude.ai and ChatGPT.

The capabilities and constraints of both wrapper and embedded AI apps are going to continue evolving quickly. So today's tradeoffs might be pretty different than tomorrow's. But it's clear what an application is, how it's distributed, and used is changing once again with AI. That means everyone will be rewriting their apps like they did for the PC, Web, and Mobile and that's a lot of opportunity for new design and development approaches.

Last time, I asked, “Why do so many long-form articles feel visually flat?” I explained that:

“Images in long-form content can (and often should) do more than illustrate. They can shape how people navigate, engage with, and interpret what they’re reading. They help set the pace, influence how readers feel, and add character that words alone can’t always convey.”

Then, I touched on the expressive possibilities of CSS Shapes and how, by using shape-outside, you can wrap text around an image’s alpha channel to add energy to a design and keep it feeling lively.

There are so many creative opportunities for using shape-outside that I’m surprised I see it used so rarely. So, how can you use it to add personality to a design? Here’s how I do it.

Patty Meltt is an up-and-coming country music sensation.

My brief: Patty Meltt is an up-and-coming country music sensation, and she needed a website to launch her new album and tour. She wanted it to be distinctive-looking and memorable, so she called Stuff & Nonsense. Patty’s not real, but the challenges of designing and developing sites like hers are.

Most shape-outside guides start with circles and polygons. That’s useful, but it answers only the how. Designers need the why — otherwise it’s just another CSS property.

Whatever shape its subject takes, every image sits inside a box. By default, text flows above or below that box. If I float an image left or right, the text wraps around the rectangle, regardless of what’s inside. That’s the limitation shape-outside overcomes.

shape-outside lets you break free from those boxes by enabling layouts that can respond to the contours of an image. That shift from images in boxes to letting the image content define the composition is what makes using shape-outside so interesting.

Solid blocks of text around straight-edged images can feel static. But text that bends around a guitar or curves around a portrait creates movement, which can make a story more compelling and engaging.

CSS shape-outside enables text to flow around any custom shape, including an image’s alpha channel (i.e., the transparent areas):

img { float: left; width: 300px; shape-outside: url('patty.webp'); shape-image-threshold: .5; shape-margin: 1rem; }

First, a quick recap.

For text to flow around elements, they need to float either left or right and have their width defined. The shape-outside URL selects an image with an alpha channel, such as a PNG or WebP. The shape-image-threshold property sets the alpha channel threshold for creating a shape. Finally, there’s the shape-margin property which — believe it or not — creates a margin around the shape.

Interactive examples from this article are available in my lab.

Multiple image shapes

When I’m adding images to a long-form article, I ask myself, “How can they help shape someone’s experience?” Flowing text around images can slow people down a little, making their experience more immersive. Visually, it brings text and image into a closer relationship, making them feel part of a shared composition rather than isolated elements.

Columns without shape-outside applied to them

Patty’s life story — from singing in honky-tonks to headlining stadiums — contains two sections: one about her, the other about her music. I added a tall vertical image of Patty to her biography and two smaller album covers to the music column:

<section id="patty"> <div> <img src="patty.webp" alt=""> [...] </div> <div> <img src="album-1.webp" alt=""> [...] <img src="album-2.webp" alt=""> [...] </div> </section>

A simple grid then creates the two columns:

#patty { display: grid; grid-template-columns: 2fr 1fr; gap: 5rem; }

I like to make my designs as flexible as I can, so instead of specifying image widths and margins in static pixels, I opted for percentages on those column widths so their actual size is relative to whatever the size of the container happens to be:

#patty > *:nth-child(1) img { float: left; width: 50%; shape-outside: url("patty.webp"); shape-margin: 2%; } #patty > *:nth-child(2) img:nth-of-type(1) { float: left; width: 45%; shape-outside: url("album-1.webp"); shape-margin: 2%; } #patty > *:nth-child(2) img:nth-of-type(2) { float: right; width: 45%; shape-outside: url("album-2.webp"); shape-margin: 2%; } Columns with shape-outside applied to them. See this example in my lab.

Text now flows around Patty’s tall image without clipping paths or polygons — just the natural silhouette of her image shaping the text.

Building rotations into images.

When an image is rotated using a CSS transform, ideally, browsers would reflow text around its rotated alpha channel. Sadly, they don’t, so it’s often necessary to build that rotation into the image.

shape-outside with a faux-centred image

For text to flow around elements, they need to be floated either to the left or right. Placing an image in the centre of the text would make Patty’s biography design more striking. But there’s no center value for floats, so how might this be possible?

Patty’s image set between two text columns. See this example in my lab.

Patty’s bio content is split across two symmetrical columns:

#dolly { display: grid; grid-template-columns: 1fr 1fr; }

To create the illusion of text flowing around both sides of her image, I first split it into two parts: one for the left and the other for the right, both of which are half, or 50%, of the original width.

Splitting the image into two pieces.

Then I placed one image in the left column, the other in the right:

<section id="dolly"> <div> <img src="patty-left.webp" alt=""> [...] </div> <div> <img src="patty-right.webp" alt=""> [...] </div> </section>

To give the illusion that text flows around both sides of a single image, I floated the left column’s half to the right:

#dolly > *:nth-child(1) img { float: right; width: 40%; shape-outside: url("patty-left.webp"); shape-margin: 2%; }

…and the right column’s half to the left, so that both halves of Patty’s image combine right in the middle:

#dolly > *:nth-child(2) img { float: left; width: 40%; shape-outside: url("patty-right.webp"); shape-margin: 2%; } Faux-centred image. See this example in my lab. Faux background image

So far, my designs for Patty’s biography have included a cut-out portrait with a clearly defined alpha channel. But, I often need to make a design that feels looser and more natural.

Faux background image. See this example in my lab.

Ordinarily, I would place a picture as a background-image, but for this design, I wanted the content to flow loosely around Patty and her guitar.

Large featured image

So, I inserted Patty’s picture as an inline image, floated it, and set its width to 100%;

<section id="kenny"> <img src="patty.webp" alt=""> [...] </section> #kenny > img { float: left; width: 100%; max-width: 100%; }

There are two methods I might use to flow text around Patty and her guitar. First, I might edit the image, removing non-essential parts to create a soft-edged alpha channel. Then, I could use the shape-image-threshold property to control which parts of the alpha channel form the contours for text wrapping:

#kenny > img { shape-outside: url("patty.webp"); shape-image-threshold: 2; } Edited image with a soft-edged alpha channel

However, this method is destructive, since much of the texture behind Patty is removed. Instead, I created a polygon clip-path and applied that as the shape-outside, around which text flows while preserving all the detail of my original image:

#kenny > img { float: left; width: 100%; max-width: 100%; shape-outside: polygon(…); shape-margin: 20px; } Original image with a non-destructive clip-path.

I have little time for writing polygon path points by hand, so I rely on Bennett Feely’s CSS clip-path maker. I add my image URL, draw a custom polygon shape, then copy the clip-path values to my shape-outside property.

Bennett Feely’s CSS clip path maker. Text between shapes

Patty Meltt likes to push the boundaries of country music, and I wanted to do the same with my design of her biography. I planned to flow text between two photomontages, where elements overlap and parts of the images spill out of their containers to create depth.

Text between shapes. See this example in my lab.

So, I made two montages with irregularly shaped alpha channels.

Irregularly shaped alpha channels

I placed both images above the content:

<section id="johnny"> <img src="patty-1.webp" alt=""> <img src="patty-2.webp" alt=""> […] </section>

…and used those same image URLs as values for shape-outside:

#johnny img:nth-of-type(1) { float: left; width: 45%; shape-outside: url("patty-1.webp"); shape-margin: 2%; } #johnny img:nth-of-type(2) { float: right; width: 35%; shape-outside: url("img/patty-2.webp"); shape-margin: 2%; }

Content now flows like a river in a country song, between the two image montages, filling the design with energy and movement.

Conclusion

Too often, images in long-form content end up boxed in and isolated, as if they were dropped into the page as an afterthought. CSS Shapes — and especially shape-outside — give us a chance to treat images and text as part of the same composition.

This matters because design isn’t just about making things usable; it’s about shaping how people feel. Wrapping text around the curve of a guitar or the edge of a portrait slows readers down, invites them to linger, and makes their experience more immersive. It brings rhythm and personality to layouts that might otherwise feel flat.

So, next time you reach for a rectangle, pause and think about how shape-outside can help turn an ordinary page into something memorable.

Getting Creative With shape-outside originally published on CSS-Tricks, which is part of the DigitalOcean family. You should get the newsletter.

In his AI Speaker Series presentation at Sutter Hill Ventures, UC Berkeley's Alexei Efros argued that data, not algorithms, drives AI progress in visual computing. Here's my notes from his talk: We're (Still) Not Giving Data Enough Credit.

Large data is necessary but not sufficient. We need to learn to be humble and to give the data the credit that it deserves. The visual computing field's algorithmic bias has obscured data's fundamental role. recognizing this reality becomes crucial for evaluating where AI breakthroughs will emerge.

The Role of Data

• Data got little respect in academia until recently as researchers spent years on algorithms, then scrambled for datasets at the last minute
• This mentality hurt us and stifled progress for a long time.
• Scientific Narcissism in AI: we prefer giving credit to human cleverness over data's role
• Human understanding relies heavily on stored experience, not just incoming sensory data.
• People see detailed steam engines in Monet's blurry brushstrokes, but the steam engine is in your head. Each person sees different versions based on childhood experiences
• People easily interpret heavily pixelated footage with brains filling in all the missing pieces
• "Mind is largely an emergent property of data" -Lance Williams
• Three landmark face detection papers achieved similar performance with completely different algorithms: neural networks. naive Bayes, and boosted cascades
• The real breakthrough wasn't algorithmic sophistication. It was realizing we needed negative data (images without faces). But 25 years later, we still credit the fancy algorithm.
• Efros's team demonstrated hole-filling in images using 2 million Flickr images with basic nearest-neighbor lookup. "The stupidest thing and it works."
• Comparing approaches with identical datasets revealed that fancy neural networks performed similarly to simple nearest neighbors.
• All the solution was in the data. Sophisticated algorithms often just perform fast lookup because the lookup contains the problem's solution.

Interpolation vs. Intelligence

• MIT's Aude Oliva's experiments reveal extraordinary human capacity for remembering natural images.
• But memory works selectively: high recognition rates for natural, meaningful images vs. near-chance performance on random textures.
• We don't have photographic memory. We remember things that are somehow on the manifold of natural experience.
• This suggests human intelligence is profoundly data-driven, but focused on meaningful experiences.
• Psychologist Alison Gopnik reframes AI as cultural technologies. Like printing presses, they collect human knowledge and make it easier to interface with it
• They're not creating truly new things, they're sophisticated interpolation systems.
• "Interpolation in sufficiently high dimensional space is indistinguishable from magic" but the magic sits in the data, not the algorithms
• Perhaps visual and textual spaces are smaller than we imagine, explaining data's effectiveness.
• 200 faces in PCA could model the whole of humanity's face. Can expand this to linear subspaces of not just pixels, but model weights themselves.
• Startup algorithm: "Is there enough data for this problem?" Text: lots of data, excellent performance. Images: less data, getting there. Video/Robotics: harder data, slower progress
• Current systems are "distillation machines" compressing human data into models.
• True intelligence may require starting from scratch: remove human civilization artifacts and bootstrap from primitive urges: hunger, jealousy, happiness
• "AI is not when a computer can write poetry. AI is when the computer will want to write poetry"

There’s the idiom that says everything looks like a nail when all you have is a hammer. I also like the one about worms in horseradish seeing the world as horseradish.

That’s what it felt like for me as I worked on music for an album of covers I released yesterday.

I was raised by my mother, a former high school art teacher (and a gifted artist in her own right), who exposed me to a lot of different tools and materials for painting and drawing. I’m convinced that’s what pointed me in the direction of web development, even though we’re talking years before the internet of AOL and 56K dial-up modems. And just as there’s art and craft to producing a creative 2D visual on paper with wet paint on a brush, there’s a level of art and craft to designing user interfaces that are written in code.

You might even say there’s a poetry to code, just as there’s code to writing poetry.

I’ve been painting with code for 20 years. HTML, CSS, JavaScript, and friends are my medium, and I’ve created a bunch of works since then. I know my mom made a bunch of artistic works in her 25+ years teaching and studying art. In a sense, we’re both artists using a different brush to produce works in different mediums.

Naturally, everything looks like code when I’m staring at a blank canvas. That’s whether the canvas is paper, a screen, some Figma artboard, or what have you. Code is my horseradish and I’ve been marinating in this horseradish ocean for quite a while.

This is what’s challenging to me about performing and producing an album of music. The work is done in a different medium. The brush is no longer code (though it can be) but sounds, be them vibrations that come from a physical instrument or digital waves that come from a programmed beat or sample.

There are parallels between painting with code and painting with sound, and it is mostly a matter of approach. The concepts, tasks, and challenges are the same, but the brush and canvas are totally different.

What’s in your stack?

Sound is no different than the web when it comes to choosing the right tools to do the work. Just as you need a stack of technical tools to produce a website or app, you will need technical tools to capture and produce sounds, and the decision affects how that work happens.

For example, my development environment might include an editor app for writing code, a virtual server to see my work locally, GitHub for version control and collaboration, some build process that compiles and deploys my code, and a host that serves the final product to everyone on the web to see.

Making music? I have recording software, microphones, gobs of guitars, and an audio interface that connects them together so that the physical sounds I make are captured and converted to digital sound waves. And, of course, I need a distributor to serve the music to be heard by others just as a host would serve code to be rendered as webpages.

Can your website’s technical stack be as simple as writing HTML in a plain text editor and manually uploading the file to a hosting service via FTP? Of course! Your album’s technical stack can just as easily be a boombox with a built in mic and recording. Be as indie or punk as you want!

Either way, you’ve gotta establish a working environment to do the work, and that environment requires you to make decisions that affect the way you work, be it code, music, or painting for that matter. Personalize your process and make it joyful.

It’s the “Recording Experience” (EX) to what we think of as Developer Experience (DX).

What’re you painting on?

If you’re painting, it could be paper. But what kind of paper? Is college-rule cool or do you need something more substantial with heavier card stock? You’re going to want something that supports the type of paint you’re using, whether it’s oil, water, acrylic… or lead? That wouldn’t be good.

On the web, you’re most often painting on a screen that measures its space in pixel units. Screens are different than paper because they’re not limited by physical constraints. Sure, the hardware may pose a constraint as far as how large a certain screen can be. But the scene itself is limitless where we can scroll to any portion of it that is not in the current frame. But please, avoid AJAX-based infinite scrolling patterns in your work for everyone’s sake.

I’m also painting music on a screen that’s as infinite as the canvas of a webpage. My recording software simply shows me a timeline and I paint sound on top of time, often layering multiple sounds at the same point in time — sound pictures, if you will.

That’s simply one way to look at it. In some apps, it’s possible to view the canvas as movements that hold buckets of sound samples.

Same thing with code. Authoring code is as likely to happen in a code editor you type into as it is to happen with a point-and-click setup in a visual interface that doesn’t require touching any code at all (Dreamweaver, anyone?). Heck, the kids are even “vibe” coding now without any awareness of how the code actually comes together. Or maybe you’re super low-fi and like to sketch your code before sitting behind a keyboard.

How’re people using it?

Web developers be like all obsessed with how their work looks on whatever device someone is using. I know you know what I’m talking about because you not only resize browsers to check responsiveness but probably also have tried opening your site (and others!) on a slew of different devices.

⚠️ Auto-playing media

It’s no different with sound. I’ve listened to each song I’ve recorded countless times because the way they sound varies from speaker to speaker. There’s one song in particular that I nearly scrapped because I struggled to get it sounding good on my AirPods Max headphones that are bass-ier than your typical speaker. I couldn’t handle the striking difference between that and a different output source that might be more widely used, like car speakers.

Will anyone actually listen to that song on a pair of AirPods Max headphones? Probably not. Then again, I don’t know if anyone is viewing my sites on some screen built into their fridge or washing machine, but you don’t see me rushing out to test that. I certainly do try to look at the sites I make on as many devices as possible to make sure nothing is completely busted.

You can’t control what device someone uses to look at a website. You can’t control what speakers someone uses to listen to music. There’s a level of user experience and quality assurance that both fields share. There’s a whole other layer about accessibility and inclusive design that fits here as well.

There is one big difference: The cringe of listening to your own voice. I never feel personally attached to the websites I make, but listening to my sounds takes a certain level of vulnerability and humility that I have to cope with.

The creative process

I mentioned it earlier, but I think the way music is created shares a lot of overlap with how websites are generally built.

For example, a song rarely (if ever) comes fully formed. Most accounts I read of musicians discussing their creative process talk about the “magic” of a melody in which it pretty much falls in the writer’s lap. It often starts as the germ of an idea and it might take minutes, days, weeks, months, or even years to develop it into a comprehensive piece of work. I keep my phone’s Voice Memos app at the ready so that I’m able to quickly “sketch” ideas that strike me in the moment. It might simply be something I hum into the phone. It could be strumming a few chords on the guitar that sound really nice together. Whatever it is, I like to think of those recordings as little low-fidelity sketches, not totally unlike sketching website layouts and content blocks with paper and pencil.

I’m partial to sketching websites on paper and pencil before jumping straight into code. It’s go time!

And, of course, there’s what you do when it’s time to release your work. I’m waist-deep in this part of the music and I can most definitely say that shipping an album has as many moving parts, if not more, than deploying a website. But they both require a lot of steps and dependencies that complicate the process. It’s no exaggeration that I’m more confused and lost about music publishing and distribution than I ever felt learning about publishing and deploying websites.

It’s perfectly understandable that someone might get lost when hosting a website. There’s so many ways to go about it, and the “right” way is shrouded in the cloak of “it depends” based on what you’re trying to accomplish.

Well, same goes for music, apparently. I’ve signed up for a professional rights organization that establishes me as the owner of the recordings, very similar to how I need to register myself as the owner of a particular web domain. On top of that, I’ve enlisted the help of a distributor to make the songs available for anyone to hear and it is exactly the same concept as needing a host to distribute your website over the wire.

I just wish I could programmatically push changes to my music catalog. Uploading and configuring the content for an album release reminds me so much of manually uploading hosted files with FTP. Nothing wrong with that, of course, but it’s certainly an opportunity to improve the developer recording experience.

So, what?

I guess what triggered this post is the realization that I’ve been in a self-made rut. Not a bad one, mind you, but more like being run by an automated script programmed to run efficiently in one direction. Working on a music project forced me into a new context where my development environment and paint brush of code are way less effective than what I need to get the job done.

It’s sort of like breaking out of the grid. My layout has been pretty fixed for some time and I’m drawing new grid tracks that open my imagination up to a whole new way of work that’s been right in front of me the entire time, but drowned in my horseradish ocean. There’s so much we can learn from other disciplines, be it music, painting, engineering, architecture, working on cars… turns out front-end development is like a lot of other things.

So, what’s your horseradish and what helps you look past it?

Same Idea, Different Paint Brush originally published on CSS-Tricks, which is part of the DigitalOcean family. You should get the newsletter.

I recently had the pleasure of speaking with Ben Lorica on O'Reilly's Generative AI in the Real World podcast about how software applications are changing in the age of AI. We discussed a number of topics including:

• The shift from "running code + database" to "URL + model" as the new definition of an application
• How this transition mirrors earlier platform shifts like the web and mobile, where initial applications looked less robust but evolved significantly over time
• How a database system designed for AI agents instead of humans operates
• The "flipped" software development process where AI coding agents allow teams to build working prototypes rapidly first, then design and integrate them into products
• How this impacts design and engineering roles, requiring new skill sets but creating more opportunities for creation
• The importance of taste and human oversight in AI systems
• And more...

You can listen to the podcast Generative AI in the Real World: Luke Wroblewski on When Databases Talk Agent-Speak (29min) on O-Reilly's site. Thanks to all the folks there for the invitation.

A couple of days ago, the Apple team released Safari 26.0! Is it a big deal? I mean, browsers release new versions all the time, where they sprinkle in a couple or few new features. They are, of course, all useful, but there aren’t usually a lot of “big leaps” between versions. Safari 26 is different, though. It introduces a lot of new stuff. To be precise, it adds: 75 new features, 3 deprecations, and 171 other improvements.

I’d officially call that a big deal.

The WebKit blog post does an amazing job breaking down each of the new (not only CSS) features. But again, there are so many that the new stuff coming to CSS deserves its own spotlight. So, today I want to check (and also try) what I think are the most interesting features coming to Safari.

If you are like me and don‘t have macOS to test Safari, you can use Playwright instead.

What’s new (to Safari)?

Safari 26 introduces several features you may already know from prior Chrome releases. And… I can’t blame Safari for seemingly lagging behind because Chrome is shipping new CSS at a scarily fast pace. I appreciate that browsers stagger releases so they can refine things against each other. Remember when Chrome initially shipped position-area as inset-area? We got better naming between the two implementations.

I think what you’ll find (as I did) that many of these overlapping features are part of the bigger effort towards Interop 2025, something WebKit is committed to. So, let’s look specifically at what’s new in Safari 26… at least that’s new to Safari.

Anchor positioning

Anchor positioning is one of my favorite features (I wrote the guide on it!), so I am so glad it’s arrived in Safari. We are now one step closer to widely available support which means we’re that much closer to using anchor positioning in our production work.

With CSS Anchor Positioning, we can attach an absolutely-positioned element (that we may call a “target”) to another element (that we may call an “anchor”). This makes creating things like tooltips, modals, and pop-ups trivial in CSS, although it can be used for a variety of layouts.

Using anchor positioning, we can attach any two elements, like these, together. It doesn’t even matter where they are in the markup.

<div class="anchor">anchor</div> <div class="target">target</div>

Heads up: Even though the source order does not matter for positioning, it does for accessibility, so it’s a good idea to establish a relationship between the anchor and target using ARIA attributes for better experiences that rely on assistive tech.

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We register the .anchor element using the anchor-name property, which takes a dashed ident. We then use that ident to attach the .target to the .anchor using the position-anchor property.

.anchor { anchor-name: --my-anchor; /* the ident */ } .target { position: absolute; position-anchor: --my-anchor; /* attached! */ }

This positions the .target at the center of the .anchor — again, no matter the source order! If we want to position it somewhere else, the simplest way is using the position-area property.

With position-area, we can define a region around the .anchor and place the .target in it. Think of it like drawing a grid of squares that are mapped to the .anchor‘s center, top, right, bottom and left.

For example, if we wish to place the target at the anchor’s top-right corner, we can write…

.target { /* ... */ position-area: top right; } CodePen Embed Fallback

This is just a taste since anchor positioning is a world unto itself. I’d encourage you to read our full guide on it.

Scroll-driven animations

Scroll-driven animations link CSS animations (created from @keyframes) to an element’s scroll position. So instead of running an animation for a given time, the animation will depend on where the user scrolls.

We can link an animation to two types of scroll-driven events:

• Linking the animation to a scrollable container using the scroll() function.
• Linking the animation to an element’s position on the viewport using the view() function.

Both of these functions are used inside the animation-timeline, which links the animation progress to the type of timeline we’re using, be it scroll or view. What’s the difference?

With scroll(), the animation runs as the user scrolls the page. The simplest example is one of those reading bars that you might see grow as you read down the page. First, we define our everyday animation and add it to the bar element:

@keyframes grow { from { transform: scaleX(0); } to { transform: scaleX(1); } } .progress { transform-origin: left center; animation: grow linear; }

Note: I am setting transform-origin to left so it the animation progresses from the left instead of expanding from the center.

Then, instead of giving the animation a duration, we can plug it into the scroll position like this:

.progress { /* ... */ animation-timeline: scroll(); }

Assuming you’re using Safari 26 or the latest version of Chrome, the bar grows in width from left to right as you scroll down the viewport.

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The view() function is similar, but it bases the animation on the element’s position when it is in view of the viewport. That way, an animation can start or stop at specific points on the page. Here’s an example making images “pop” up as they enter view.

@keyframes popup { from { opacity: 0; transform: translateY(100px); } to { opacity: 1; transform: translateY(0px); } } img { animation: popup linear; }

Then, to make the animation progress as the element enters the viewport, we plug the animation-timeline to view().

img { animation: popup linear; animation-timeline: view(); }

If we leave like this, though, the animation ends just as the element leaves the screen. The user doesn’t see the whole thing! What we want is for the animation to end when the user is in the middle of the viewport so the full timeline runs in view.

This is where we can reach for the animation-range property. It lets us set the animation’s start and end points relative to the viewport. In this specific example, let’s say I want the animation to start when the element enters the screen (i.e., the 0% mark) and finishes a little bit before it reaches the direct center of the viewport (we’ll say 40%):

img { animation: popup linear; animation-timeline: view(); animation-range: 0% 40%; } CodePen Embed Fallback

Once again, scroll-driven animations go way beyond these two basic examples. For a quick intro to all there is to them, I recommend Geoff’s notes.

I feel safer using scroll-drive animations in my production work because it’s more of a progressive enhancement that won’t break an experience even if it is not supported by the browser. Even so, someone may prefer reduced (or no) animation at all, meaning we’d better progressively enhance it anyway with prefers-reduced-motion.

The progress() function

This is another feature we got in Chrome that has made its way to Safari 26. Funny enough, I missed it in Chrome when it released a few months ago, so it makes me twice as happy to see such a handy feature baked into two major browsers.

The progress() function tells you how much a value has progressed in a range between a starting point and an ending point:

progress(<value>, <start>, <end>)

If the <value> is less than the <start>, the result is 0. If the <value> reaches the <end>, the result is 1. Anything in between returns a decimal between 0 and 1.

Technically, this is something we can already do in a calc()-ulation:

calc((value - start) / (end - start))

But there’s a key difference! With progress(), we can calculate values from mixed data types (like adding px to rem), which isn’t currently possible with calc(). For example, we can get the progress value formatted in viewport units from a numeric range formatted in pixels:

progress(100vw, 400px, 1000px);

…and it will return 0 when the viewport is 400px, and as the screen grows to 1000px, it progresses to 1. This means it can typecast different units into a number, and as a consequence, we can transition properties like opacity (which takes a number or percentage) based on the viewport (which is a distance length).

There’s another workaround that accomplishes this using tan() and atan2() functions. I have used that approach before to create smooth viewport transitions. But progress() greatly simplifies the work, making it much more maintainable.

Case in point: We can orchestrate multiple animations as the screen size changes. This next demo takes one of the demos I made for the article about tan() and atan2(), but swaps that out with progress(). Works like a charm!

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That’s a pretty wild example. Something more practical might be reducing an image’s opacity as the screen shrinks:

img { opacity: clamp(0.25, progress(100vw, 400px, 1000px), 1); }

Go ahead and resize the demo to update the image’s opacity, assuming you’re looking at it in Safari 26 or the latest version of Chrome.

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I’ve clamp()-ed the progress() between 0.25 and 1. But, by default, progress() already clamps the <value> between 0 and 1. According to the WebKit release notes, the current implementation isn’t clamped by default, but upon testing, it does seem to be. So, if you’re wondering why I’m clamping something that’s supposedly clamped already, that’s why.

An unclamped version may come in the future, though.

Self-alignment in absolute positioning

And, hey, check this out! We can align-self and justify-self content inside absolutely-positioned elements. This isn’t as big a deal as the other features we’ve looked at, but it does have a handy use case.

For example, I sometimes want to place an absolutely-positioned element directly in the center of the viewport, but inset-related properties (i.e., top, right, bottom, left, etc.) are relative to the element’s top-left corner. That means we don’t get perfectly centered with something like this as we’d expect:

.absolutely-positioned { position: absolute; top: 50%; left: 50%; }

From here, we could translate the element by half to get things perfectly centered. But now we have the center keyword supported by align-self and justify-self, meaning fewer moving pieces in the code:

.absolutely-positioned { position: absolute; justify-self: center; }

Weirdly enough, I noticed that align-self: center doesn’t seem to center the element relative to the viewport, but instead relative to itself. I found out that can use the anchor-center value to center the element relative to its default anchor, which is the viewport in this specific example:

.absolutely-positioned { position: absolute; align-self: anchor-center; justify-self: center; } CodePen Embed Fallback

And, of course, place-self is a shorthand for the align-self and justify-self properties, so we could combine those for brevity:

.absolutely-positioned { position: absolute; place-self: anchor-center center; } What’s new (for the web)?

Safari 26 isn’t just about keeping up with Chrome. There’s a lot of exciting new stuff in here that we’re getting our hands on for the first time, or that is refined from other browser implementations. Let’s look at those features.

The constrast-color() function

The constrast-color() isn’t new by any means. It’s actually been in Safari Technology Preview since 2021 where it was originally called color-contrast(). In Safari 26, we get the updated naming as well as some polish.

Given a certain color value, contrast-color() returns either white or black, whichever produces a sharper contrast with that color. So, if we were to provide coral as the color value for a background, we can let the browser decide whether the text color is more contrasted with the background as either white or black:

h1 { --bg-color: coral; background-color: var(--bg-color); color: contrast-color(var(--bg-color)); } CodePen Embed Fallback

Our own Daniel Schwarz recently explored the contrast-color() function and found it’s actually not that great at determining the best contrast between colors:

Undoubtedly, the number one shortcoming is that contrast-color() only resolves to either black or white. If you don’t want black or white, well… that sucks.

It sucks because there are cases where neither white nor black produces enough contrast with the provided color to meet WCAG color contrast guidelines. There is an intent to extend contrast-color() so it can return additional color values, but there still would be concerns about how exactly contrast-color() arrives at the “best” color, since we would still need to take into consideration the font’s width, size, and even family. Always check the actual contrast!

So, while it’s great to finally have constrat-color(), I do hope we see improvements added in the future.

Pretty text wrapping

Safari 26 also introduces text-wrap: pretty, which is pretty (get it?) straightforward: it makes paragraphs wrap in a prettier way.

You may remember that Chrome shipped this back in 2023. But take notice that there is a pretty (OK, that’s the last time) big difference between the implementations. Chrome only avoids typographic orphans (short last lines). Safari does more to prettify the way text wraps:

• Prevents short lines. Avoids single words at the end of the paragraph.
• Improves rag. Keeps each line relatively the same length.
• Reduces hyphenation. When enabled, hyphenation improves rag but also breaks words apart. In general, hyphenation should be kept to a minimum.

The WebKit blog gets into much greater detail if you’re curious about what considerations they put into it.

Safari takes additional actions to ensure “pretty” text wrapping, including the overall ragging along the text. This is just the beginning!

I think these are all the CSS features coming to Safari that you should look out for, but I don’t want you to think they are the only features in the release. As I mentioned at the top, we’re talking about 75 new Web Platform features, including HDR Images, support for SVG favicons, logical property support for overflow properties, margin trimming, and much, much more. It’s worth perusing the full release notes.

Touring New CSS Features in Safari 26 originally published on CSS-Tricks, which is part of the DigitalOcean family. You should get the newsletter.

I always see this Google Gemini button up in the corner in Gmail. When you hover over it, it does this cool animation where the little four-pointed star spins and the outer shape morphs between a couple different shapes that are also spinning.

I challenged myself to recreate the button using the new CSS shape() function sprinkled with animation to get things pretty close. Let me walk you through it.

Drawing the Shapes

Breaking it down, we need five shapes in total:

1. Four-pointed star
2. Flower-ish thing (yes, that’s the technical term)
3. Cylinder-ish thing (also the correct technical term)
4. Rounded hexagon
5. Circle

I drew these shapes in a graphics editing program (I like Affinity Designer, but any app that lets you draw vector shapes should work), outputted them in SVG, and then used a tool, like Temani Afif’s generator, to translate the SVG paths the program generated to the CSS shape() syntax.

Now, before I exported the shapes from Affinity Designer, I made sure the flower, hexagon, circle, and cylinder all had the same number of anchor points. If they don’t have the same number, then the shapes will jump from one to the next and won’t do any morphing. So, let’s use a consistent number of anchor points in each shape — even the circle — and we can watch these shapes morph into each other.

I set twelve anchor points on each shape because that was the highest amount used (the hexagon had two points near each curved corner).

Something related (and possibly hard to solve, depending on your graphics program) is that some of my shapes were wildly contorted when animating between shapes. For example, many shapes became smaller and began spinning before morphing into the next shape, while others were much more seamless. I eventually figured out that the interpolation was matching each shape’s starting point and continued matching points as it followed the shape.

The result is that the matched points move between shapes, so if the starting point for one shape is on opposite side of the starting point of the second shape, a lot of movement is necessary to transition from one shape’s starting point to the next shape’s starting point.

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Luckily, the circle was the only shape that gave me trouble, so I was able to spin it (with some trial and error) until its starting point more closely matched the other starting points.

Another issue I ran into was that the cylinder-ish shape had two individual straight lines in shape() with line commands rather than using the curve command. This prevented the animation from morphing into the next shape. It immediately snapped to the next image without animating the transition, skipping ahead to the next shape (both when going into the cylinder and coming out of it).

I went back into Affinity Designer and ever-so-slightly added curvature to the two lines, and then it morphed perfectly. I initially thought this was a shape() quirk, but the same thing happened when I attempted the animation with the path() function, suggesting it’s more an interpolation limitation than it is a shape() limitation.

Once I finished adding my shape() values, I defined a CSS variable for each shape. This makes the later uses of each shape() more readable, not to mention easier to maintain. With twelve lines per shape the code is stinkin’ long (technical term) so we’ve put it behind an accordion menu.

View Shape Code :root { --hexagon: shape( evenodd from 6.47% 67.001%, curve by 0% -34.002% with -1.1735% -7.7% / -1.1735% -26.302%, curve by 7.0415% -12.1965% with 0.7075% -4.641% / 3.3765% -9.2635%, curve by 29.447% -17.001% with 6.0815% -4.8665% / 22.192% -14.1675%, curve by 14.083% 0% with 4.3725% -1.708% / 9.7105% -1.708%, curve by 29.447% 17.001% with 7.255% 2.8335% / 23.3655% 12.1345%, curve by 7.0415% 12.1965% with 3.665% 2.933% / 6.334% 7.5555%, curve by 0% 34.002% with 1.1735% 7.7% / 1.1735% 26.302%, curve by -7.0415% 12.1965% with -0.7075% 4.641% / -3.3765% 9.2635%, curve by -29.447% 17.001% with -6.0815% 4.8665% / -22.192% 14.1675%, curve by -14.083% 0% with -4.3725% 1.708% / -9.7105% 1.708%, curve by -29.447% -17.001% with -7.255% -2.8335% / -23.3655% -12.1345%, curve by -7.0415% -12.1965% with -3.665% -2.933% / -6.334% -7.5555%, close ); --flower: shape( evenodd from 17.9665% 82.0335%, curve by -12.349% -32.0335% with -13.239% -5.129% / -18.021% -15.402%, curve by -0.0275% -22.203% with -3.1825% -9.331% / -3.074% -16.6605%, curve by 12.3765% -9.8305% with 2.3835% -4.3365% / 6.565% -7.579%, curve by 32.0335% -12.349% with 5.129% -13.239% / 15.402% -18.021%, curve by 20.4535% -0.8665% with 8.3805% -2.858% / 15.1465% -3.062%, curve by 11.58% 13.2155% with 5.225% 2.161% / 9.0355% 6.6475%, curve by 12.349% 32.0335% with 13.239% 5.129% / 18.021% 15.402%, curve by 0.5715% 21.1275% with 2.9805% 8.7395% / 3.0745% 15.723%, curve by -12.9205% 10.906% with -2.26% 4.88% / -6.638% 8.472%, curve by -32.0335% 12.349% with -5.129% 13.239% / -15.402% 18.021%, curve by -21.1215% 0.5745% with -8.736% 2.9795% / -15.718% 3.0745%, curve by -10.912% -12.9235% with -4.883% -2.2595% / -8.477% -6.6385%, close ); --cylinder: shape( evenodd from 10.5845% 59.7305%, curve by 0% -19.461% with -0.113% -1.7525% / -0.11% -18.14%, curve by 10.098% -26.213% with 0.837% -10.0375% / 3.821% -19.2625%, curve by 29.3175% -13.0215% with 7.2175% -7.992% / 17.682% -13.0215%, curve by 19.5845% 5.185% with 7.1265% 0% / 13.8135% 1.887%, curve by 9.8595% 7.9775% with 3.7065% 2.1185% / 7.035% 4.8195%, curve by 9.9715% 26.072% with 6.2015% 6.933% / 9.4345% 16.082%, curve by 0% 19.461% with 0.074% 1.384% / 0.0745% 17.7715%, curve by -13.0065% 29.1155% with -0.511% 11.5345% / -5.021% 21.933%, curve by -26.409% 10.119% with -6.991% 6.288% / -16.254% 10.119%, curve by -20.945% -5.9995% with -7.6935% 0% / -14.8755% -2.199%, curve by -8.713% -7.404% with -3.255% -2.0385% / -6.1905% -4.537%, curve by -9.7575% -25.831% with -6.074% -6.9035% / -9.1205% -15.963%, close ); --star: shape( evenodd from 50% 24.787%, curve by 7.143% 18.016% with 0% 0% / 2.9725% 13.814%, curve by 17.882% 7.197% with 4.171% 4.2025% / 17.882% 7.197%, curve by -17.882% 8.6765% with 0% 0% / -13.711% 4.474%, curve by -7.143% 16.5365% with -4.1705% 4.202% / -7.143% 16.5365%, curve by -8.6115% -16.5365% with 0% 0% / -4.441% -12.3345%, curve by -16.4135% -8.6765% with -4.171% -4.2025% / -16.4135% -8.6765%, curve by 16.4135% -7.197% with 0% 0% / 12.2425% -2.9945%, curve by 8.6115% -18.016% with 4.1705% -4.202% / 8.6115% -18.016%, close ); --circle: shape( evenodd from 13.482% 79.505%, curve by -7.1945% -12.47% with -1.4985% -1.8575% / -6.328% -10.225%, curve by 0.0985% -33.8965% with -4.1645% -10.7945% / -4.1685% -23.0235%, curve by 6.9955% -12.101% with 1.72% -4.3825% / 4.0845% -8.458%, curve by 30.125% -17.119% with 7.339% -9.1825% / 18.4775% -15.5135%, curve by 13.4165% 0.095% with 4.432% -0.6105% / 8.9505% -0.5855%, curve by 29.364% 16.9% with 11.6215% 1.77% / 22.102% 7.9015%, curve by 7.176% 12.4145% with 3.002% 3.7195% / 5.453% 7.968%, curve by -0.0475% 33.8925% with 4.168% 10.756% / 4.2305% 22.942%, curve by -7.1135% 12.2825% with -1.74% 4.4535% / -4.1455% 8.592%, curve by -29.404% 16.9075% with -7.202% 8.954% / -18.019% 15.137%, curve by -14.19% -0.018% with -4.6635% 0.7255% / -9.4575% 0.7205%, curve by -29.226% -16.8875% with -11.573% -1.8065% / -21.9955% -7.9235%, close ); }

If all that looks like gobbledygook to you, it largely does to me too (and I wrote the shape() Almanac entry). As I said above, I converted them from stuff I drew to shape()s with a tool. If you can recognize the shapes from the custom property names, then you’ll have all you need to know to keep following along.

Breaking Down the Animation

After staring at the Gmail animation for longer than I would like to admit, I was able to recognize six distinct phases:

First, on hover:

1. The four-pointed star spins to the right and changes color.
2. The fancy blue shape spreads out from underneath the star shape.
3. The fancy blue shape morphs into another shape while spinning.
4. The purplish color is wiped across the fancy blue shape.

Then, after hover:

5. The fancy blue shape contracts (basically the reverse of Phase 2).
6. The four-pointed star spins left and returns to its initial color (basically the reverse of Phase 1).

That’s the run sheet we’re working with! We’ll write the CSS for all that in a bit, but first I’d like to set up the HTML structure that we’re hooking into.

The HTML

I’ve always wanted to be one of those front-enders who make jaw-dropping art out of CSS, like illustrating the Sistine chapel ceiling with a single div (cue someone commenting with a CodePen doing just that). But, alas, I decided I needed two divs to accomplish this challenge, and I thank you for looking past my shame. To those of you who turned up your nose and stopped reading after that admission: I can safely call you a Flooplegerp and you’ll never know it.

(To those of you still with me, I don’t actually know what a Flooplegerp is. But I’m sure it’s bad.)

Because the animation needs to spread out the blue shape from underneath the star shape, they need to be two separate shapes. And we can’t shrink or clip the main element to do this because that would obscure the star.

So, yeah, that’s why I’m reaching for a second div: to handle the fancy shape and how it needs to move and interact with the star shape.

<div id="geminianimation"> <div></div> </div> The Basic CSS Styling

Each shape is essentially defined with the same box with the same dimensions and margin spacing.

#geminianimation { width: 200px; aspect-ratio: 1/1; margin: 50px auto; position: relative; }

We can clip the box to a particular shape using a pseudo-element. For example, let’s clip a star shape using the CSS variable (--star) we defined for it and set a background color on it:

#geminianimation { width: 200px; aspect-ratio: 1; margin: 50px auto; position: relative; &::before { content: ""; clip-path: var(--star); width: 100%; height: 100%; position: absolute; background-color: #494949; } } CodePen Embed Fallback

We can hook into the container’s child div and use it to establish the animation’s starting shape, which is the flower (clipped with our --flower variable):

#geminianimation div { width: 100%; height: 100%; clip-path: var(--flower); background: linear-gradient(135deg, #217bfe, #078efb, #ac87eb, #217bfe); }

What we get is a star shape stacked right on top of a flower shape. We’re almost done with our initial CSS, but in order to recreate the animated color wipes, we need a much larger surface that allows us to “change” colors by moving the background gradient’s position. Let’s move the gradient so that it is declared on a pseudo element instead of the child div, and size it up by 400% to give us additional breathing room.

#geminianimation div { width: 100%; height: 100%; clip-path: var(--flower); &::after { content: ""; background: linear-gradient(135deg, #217bfe, #078efb, #ac87eb, #217bfe); width: 400%; height: 400%; position: absolute; } }

Now we can clearly see how the shapes are positioned relative to each other:

CodePen Embed Fallback Animating Phases 1 and 6

Now, I’ll admit, in my own hubris, I’ve turned up my very own schnoz at the humble transition property because my thinking is typically, Transitions are great for getting started in animation and for quick things, but real animations are done with CSS keyframes. (Perhaps I, too, am a Flooplegerp.)

But now I see the error of my ways. I can write a set of keyframes that rotate the star 180 degrees, turn its color white(ish), and have it stay that way for as long as the element is hovered. What I can’t do is animate the star back to what it was when the element is un-hovered.

I can, however, do that with the transition property. To do this, we add transition: 1s ease-in-out; on the ::before, adding the new background color and rotating things on :hover over the #geminianimation container. This accounts for the first and sixth phases of the animation we outlined earlier.

#geminianimation { &::before { /* Existing styles */ transition: 1s ease-in-out; } &:hover { &::before { transform: rotate(180deg); background-color: #FAFBFE; } } } Animating Phases 2 and 5

We can do something similar for the second and fifth phases of the animation since they are mirror reflections of each other. Remember, in these phases, we’re spreading and contracting the fancy blue shape.

We can start by shrinking the inner div’s scale to zero initially, then expand it back to its original size (scale: 1) on :hover (again using transitions):

#geminianimation { div { scale: 0; transition: 1s ease-in-out; } &:hover { div { scale: 1; } } CodePen Embed Fallback Animating Phase 3

Now, we very well could tackle this with a transition like we did the last two sets, but we probably should not do it… that is, unless you want to weep bitter tears and curse the day you first heard of CSS… not that I know from personal experience or anything… ha ha… ha.

CSS keyframes are a better fit here because there are multiple states to animate between that would require defining and orchestrating several different transitions. Keyframes are more adept at tackling multi-step animations.

What we’re basically doing is animating between different shapes that we’ve already defined as CSS variables that clip the shapes. The browser will handle interpolating between the shapes, so all we need is to tell CSS which shape we want clipped at each phase (or “section”) of this set of keyframes:

@keyframes shapeshift { 0% { clip-path: var(--circle); } 25% { clip-path: var(--flower); } 50% { clip-path: var(--cylinder); } 75% { clip-path: var(--hexagon); } 100% { clip-path: var(--circle); } }

Yes, we could combine the first and last keyframes (0% and 100%) into a single step, but we’ll need them separated in a second because we also want to animate the rotation at the same time. We’ll set the initial rotation to 0turn and the final rotation 1turn so that it can keep spinning smoothly as long as the animation is continuing:

@keyframes shapeshift { 0% { clip-path: var(--circle); rotate: 0turn; } 25% { clip-path: var(--flower); } 50% { clip-path: var(--cylinder); } 75% { clip-path: var(--hexagon); } 100% { clip-path: var(--circle); rotate: 1turn; } }

Note: Yes, turn is indeed a CSS unit, albeit one that often goes overlooked.

We want the animation to be smooth as it interpolates between shapes. So, I’m setting the animation’s timing function with ease-in-out. Unfortunately, this will also slow down the rotation as it starts and ends. However, because we’re both beginning and ending with the circle shape, the fact that the rotation slows coming out of 0% and slows again as it heads into 100% is not noticeable — a circle looks like a circle no matter its rotation. If we were ending with a different shape, the easing would be visible and I would use two separate sets of keyframes — one for the shape-shift and one for the rotation — and call them both on the #geminianimation child div .

#geminianimation:hover { div { animation: shapeshift 5s ease-in-out infinite forwards; } } Animating Phase 4

That said, we still do need one more set of keyframes, specifically for changing the shape’s color. Remember how we set a linear gradient on the parent container’s ::after pseudo, then we also increased the pseudo’s width and height? Here’s that bit of code again:

#geminianimation div { width: 100%; height: 100%; clip-path: var(--flower); &::after { content: ""; background: linear-gradient(135deg, #217bfe, #078efb, #ac87eb, #217bfe); width: 400%; height: 400%; position: absolute; } }

The gradient is that large because we’re only showing part of it at a time. And that means we can translate the gradient’s position to move the gradient at certain keyframes. 400% can be nicely divided into quarters, so we can move the gradient by, say, three-quarters of its size. Since its parent, the #geminianimation div, is already spinning, we don’t need any fancy movements to make it feel like the color is coming from different directions. We just translate it linearly and the spin adds some variability to what direction the color wipe comes from.

@keyframes gradientMove { 0% { translate: 0 0; } 100% { translate: -75% -75%; } } One final refinement

Instead of using the flower as the default shape, let’s change it to circle. This smooths things out when the hover interaction causes the animation to stop and return to its initial position.

And there you have it:

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We did it! Is this exactly how Google accomplished the same thing? Probably not. In all honesty, I never inspected the animation code because I wanted to approach it from a clean slate and figure out how I would do it purely in CSS.

That’s the fun thing about a challenge like this: there are different ways to accomplish the same thing (or something similar), and your way of doing it is likely to be different than mine. It’s fun to see a variety of approaches.

Which leads me to ask: How would you have approached the Gemini button animation? What considerations would you take into account that maybe I haven’t?

Recreating Gmail’s Google Gemini Animation originally published on CSS-Tricks, which is part of the DigitalOcean family. You should get the newsletter.

In her talk Reveal the Hidden Forces Driving User Behavior at Future Product Days, Sarah Thompson shared insights on how to leverage behavioral science to create more effective user experiences. Here's my notes from her talk:

• While AI technology evolves exponentially, the human brain has not had a meaningful update in approximately 40,000 years so we're still designing for the "caveman brain"
• This unchanging human element provides a stable foundation for design that doesn't change with every wave of technology
• Behavioral science matters more than ever because we now have tools that allow us to scale faster than ever
• All decisions are emotional because there is an system one (emotional) part of the brain that makes decisions first. This part of the brain lights up 10 seconds before a person is even aware they made a decision
• System 1 thinking is fast, automatic, and helped us survive through gut reactions. It still runs the show today but uses shortcuts and over 180 known cognitive biases to navigate complexity
• Every time someone makes a decision, the emotional brain instantly predicts whether there are more costs or gains to taking action. More costs? Don't do it. More gains? Move forward
• The emotional brain only cares about six intuitive categories of costs and gains: internal (mental, emotional, physical) and external (social, material, temporal)
• Mental: "Thinking is hard" We evolved to conserve mental effort - people drop off with too many choices, stick with defaults. Can the user understand what they need to do immediately?
• Social: "We are wired to belong" We evolved to treat social costs as life or death situations. Does this make users feel safe, seen, or part of a group? Or does it raise embarrassment or exclusion?
• Emotional: "Automatic triggers" Imagery and visuals are the fastest way to set emotional tone. What automatic trigger (positive or negative) might this design bring up for someone?
• Physical: "We're wired to conserve physical effort" Physical gains include tap-to-pay, facial recognition, wearable data collection. Can I remove real or perceived physical effort?
• Material: "Our brains evolved in scarcity" Scarcity tactics like "Bob booked this three minutes ago" drive immediate action. Are we asking people to give something up or are we giving them something in return?
• Temporal: "We crave immediate rewards" Any time people have to wait, we see drop off. Can we give immediate reward or make people feel like they're saving time?
• You can't escape the caveman brain, but you can design for it.

In his How to solve the right problem with AI presentation at Future Product Days, Dave Crawford shared insights on how to effectively integrate AI into established products without falling into common traps. Here are my notes from his talk:

• Many teams have been given the directive to "go add some AI" to their products. With AI as a technology, it's very easy to fall into the trap of having an AI hammer where every problem looks like an AI nail.
• We need to focus on using AI where it's going to give the most value to users. It's not what we can do with AI, it's what makes sense to do with AI.

AI Interaction Patterns

• People typically encounter AI through four main interaction types
• Discovery AI: Helps people find, connect, and learn information, often taking the place of search
• Analytical AI: Analyzes data to provide insights, such as detecting cancer from medical scans
• Generative AI: Creates content like images, text, video, and more
• Functional AI: Actually gets stuff done by performing actions directly or interacting with other services
• AI interaction patterns exist on a context spectrum from high user burden to low user burden
• Open Text-Box Chat: Users must provide all context (ChatGPT, Copilot) - high overhead for users
• Sidecar Experience: Has some context about what's happening in the rest of the app, but still requires context switching
• Embedded: Highly contextual AI that appears directly in the flow of user's work
• Background: Agents that perform tasks autonomously without direct user interaction

Principles for AI Product Development

• Think Simply: Make something that makes sense and provides clear value. Users need to know what to expect from your AI experience
• Think Contextually: Can you make the experience more relevant for people using available context? Customize experiences within the user's workflow
• Think Big: AI can do a lot, so start big and work backwards.
• Mine, Reason, Infer: Make use of the information people give you.
• Think Proactively: What kinds of things can you do for people before they ask?
• Think Responsibly: Consider environmental and cost impacts of using AI.
• We should focus on delivering value first over delightful experiences

Problems for AI to Solve

• Boring tasks that users find tedious
• Complex activities users currently offload to other services
• Long-winded processes that take too much time
• Frustrating experiences that cause user pain
• Repetitive tasks that could be automated
• Don't solve problems that are already well-solved with simpler solutions
• Not all AI needs to be a chat interface. Sometimes traditional UI is better than AI
• Users' tolerance and forgiveness of AI is really low. It takes around 8 months for a user to want to try an AI product again after a bad experience
• We're now trying to find the right problems to solve rather than finding the right solutions to problems. Build things that solve real problems, not just showcase AI capabilities

In her The AI Adoption Gap: Why Great Features Go Unused talk at Future Product Days in Copenhagen, Kate Moran shared insights on why users don't utilize AI features in digital products. Here's my notes from her talk:

• The best way to understand the people we're creating digital products for is to talk to them and watch them use our products.
• Most people are not looking for AI features nor are they expecting them. People are task-focused, they're just trying to get something done and move on.
• Top three reasons people don't use AI features: they have no reason to use it, they don't see it, they don't know how to use it.
• There are other issues like in enterprise use cases, trust. But these are the main ones.
• People don't care about the technology, they care about the outcome. AI-powered is not a value-add. Solving someone's problem is a value-add.
• Amazon introduced a shopping assistant that when tested, people really liked because the assistant has a lot of context: what you bought before, what you are looking at now, and more
• However, people could not find this feature and did not know how to use it. The button is labeled "Rufus" people don't associate this with something that helps them get answers about their shopping.
• Findability is how well you can locate something you are looking for. Discoverability is finding something you weren't looking for.
• In interfaces that people use a lot (are familiar with), they often miss new features especially when they are introduced with a single action among many others
• Designers are making basic mistakes that don't have anything to do with AI (naming, icons, presentation)
• People say conversational interfaces are the easiest to use but it's not true. Open text fields feel like search, so people treat them like smarter search instead of using the full capability of AI systems
• People have gotten used to using succinct keywords in text fields instead of providing lots of context to AI models that produce better outcomes
• Smaller-scope AI features like automatic summaries that require no user interaction perform well because they integrate seamlessly into existing workflows
• These adoption challenges are not exclusive to AI but apply to any new feature, As a result, all your existing design skills remain highly valuable for AI features.

In his talk The Future of Product Creators at Future Product Days in Copenhagen, Tobias Ahlin argued that divergent opinions and debate, not just raw capability, are the missing factors for achieving useful outcomes from AI systems. Here are my notes from his presentation:

• Many people are exposing a future vision where parallel agents creating products and features on demand.
• 2025 marked the year when agentic workflows became part of daily product development. AI agents quantifiably outperform humans on standardized tests: reading, writing, math, coding, and even specialized fields.
• Yet we face the 100 interns problem: managing agents that are individually smarter but "have no idea where they're going"

Limitations of Current Systems

• Fundamental reasoning gaps: AI models have fundamental reasoning gaps. For example, AI can calculate rock-paper-scissors odds while failing to understand it has a built-in disadvantage by going second.
• Fatal mistakes in real-world applications: suggesting toxic glue for pizza, recommending eating rocks for minerals.
• Performance plateau problem: Unlike humans who improve with sustained effort, AI agents plateau after initial success and cannot meaningfully progress even with more time
• Real-world vs. benchmark performance: Research from Monitor shows 63% of AI-generated code fails tests, with 0% working without human intervention

Social Nature of Reasoning

• True reasoning is fundamentally a social function, "optimized for debate and communication, not thinking in isolation"
• Court systems exemplify this: adversarial arguments sharpen and improve each other through conflict
• Individual biases can complement each other when structured through critical scrutiny systems
• Teams naturally create conflicting interests: designers want to do more, developers prefer efficiency, PMs balance scope.This tension drives better outcomes
• AI significantly outperforms humans in creativity tests. In a Cornell study, GPT-4 performed better than 90.6% of humans in idea generation, with AI ideas being seven times more likely to rank in the top 10%
• So the cost of generating ideas is moving towards zero but human capability remains capped by our ability to evaluate and synthesize those ideas

Future of AI Agents

• Current agents primarily help with production but future productivity requires and equal amount of effort in evaluation and synthesis.
• Institutionalized disconfirmation: creating systems where disagreement drives clarity, similar to scientific peer review
• Agents designed to disagree in loops: one agent produces code, another evaluates it, creating feedback systems that can overcome performance plateaus
• True reasoning will come from agents that are designed to disagree in loops rather than simple chain-of-thought approaches

CSS typed arithmetic is genuinely exciting! It opens the door to new kinds of layout composition and animation logic we could only hack before. The first time I published something that leaned on typed arithmetic was in this animation:

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But before we dive into what is happening in there, let’s pause and get clear on what typed arithmetic actually is and why it matters for CSS.

Browser Support: The CSS feature discussed in this article, typed arithmetic, is on the cutting edge. As of the time of writing, browser support is very limited and experimental. To ensure all readers can understand the concepts, the examples throughout this article are accompanied by videos and images, demonstrating the results for those whose browsers do not yet support this functionality. Please check resources like MDN or Can I Use for the latest support status.

The Types

If you really want to get what a “type” is in CSS, think about TypeScript. Now forget about TypeScript. This is a CSS article, where semantics actually matter.

In CSS, a type describes the unit space a value lives in, and is called a data-type. Every CSS value belongs to a specific type, and each CSS property and function only accepts the data type (or types) it expects.

• Properties like opacity or scale use a plain <number> with no units.
• width, height, other box metrics, and many additional properties use <length> units like px, rem, cm, etc.
• Functions like rotate() or conic-gradient() use an <angle> with deg, rad, or turn.
• animation and transition use <time> for their duration in seconds (s) or milliseconds (ms).

Note: You can identify CSS data types in the specs, on MDN, and other official references by their angle brackets: <data-type>.

There are many more data types like <percentage>, <frequency>, and <resolution>, but the types mentioned above cover most of our daily use cases and are all we will need for our discussion today. The mathematical concept remains the same for (almost) all types.

I say “almost” all types for one reason: not every data type is calculable. For instance, types like <color>, <string>, or <image> cannot be used in mathematical operations. An expression like "foo" * red would be meaningless. So, when we discuss mathematics in general, and typed arithmetic in particular, it is crucial to use types that are inherently calculable, like <length>, <angle>, or <number>.

The Rules of Typed Arithmetic

Even when we use calculable data types, there are still limitations and important rules to keep in mind when performing mathematical operations on them.

Addition and Subtraction

Sadly, a mix-and-match approach doesn’t really work here. Expressions like calc(3em + 45deg) or calc(6s - 3px) will not produce a logical result. When adding or subtracting, you must stick to the same data type.

Of course, you can add and subtract different units within the same type, like calc(4em + 20px) or calc(300deg - 1rad).

Multiplication

With multiplication, you can only multiply by a plain <number> type. For example: calc(3px * 7), calc(10deg * 6), or calc(40ms * 4). The result will always adopt the type and unit of the first value, with the new value being the product of the multiplication.

But why can you only multiply by a number? If we tried something like calc(10px * 10px) and assumed it followed “regular” math, we would expect a result of 100px². However, there are no squared pixels in CSS, and certainly no square degrees (though that could be interesting…). Because such a result is invalid, CSS only permits multiplying typed values by unitless numbers.

Division

Here, too, mixing and matching incompatible types is not allowed, and you can divide by a number just as you can multiply a number. But what happens when you divide a type by the same type?

Hint: this is where things get interesting.

Again, if we were thinking in terms of regular math, we would expect the units to cancel each other out, leaving only the calculated value. For example, 90x / 6x = 15. In CSS, however, this isn’t the case. Sorry, it wasn’t the case.

Previously, an expression like calc(70px / 10px) would have been invalid. But starting with Safari 18.2 and Chrome 140 (and hopefully soon in all other browsers), this expression now returns a valid number, which winds up being 7 in this case. This is the major change that typed arithmetic enables.

Is that all?!

That little division? Is that the big thing I called “genuinely exciting”? Yes! Because this one little feature opens the door to a world of creative possibilities. Case in point: we can convert values from one data type to another and mathematically condition values of one type based on another, just like in the swirl example I demoed at the top.

So, to understand what is happening there, let’s look at a more simplified swirl:

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I have a container<div> with 36 <i> elements in the markup that are arranged in a spiral with CSS. Each element has an angle relative to the center point, rotate(var(--angle)), and a distance from that center point, translateX(var(--distance)).

The angle calculation is quite direct. I take the index of each <i> element using sibling-index() and multiply it by 10deg. So, the first element with an index of 1 will be rotated by 10 degrees (1 * 10deg), the second by 20 degrees (2 * 10deg), the third by 30 degrees (3 * 10deg), and so on.

i { --angle: calc(sibling-index() * 10deg); }

As for the distance, I want it to be directly proportional to the angle. I first use typed arithmetic to divide the angle by 360 degrees: var(--angle) / 360deg.

This returns the angle’s value, but as a unitless number, which I can then use anywhere. In this case, I can multiply it by a <length> value (e.g. 180px) that determines the element’s distance from the center point.

i { --angle: calc(sibling-index() * 10deg); --distance: calc(var(--angle) / 360deg * 180px); }

This way, the ratio between the angle and the distance remains constant. Even if we set the angle of each element differently, or to a new value, the elements will still align on the same spiral.

The Importance of the Divisor’s Unit

It’s important to clarify that when using typed arithmetic this way, you get a unitless number, but its value is relative to the unit of the divisor.

In our simplified spiral, we divided the angle by 360deg. The resulting unitless number, therefore, represents the value in degrees. If we had divided by 1turn instead, the result would be completely different — even though 1turn is equivalent to 360deg, the resulting unitless number would represent the value in turns.

A clearer example can be seen with <length> values.

Let’s say we are working with a screen width of 1080px. If we divide the screen width (100vw) by 1px, we get the number of pixels that fit into the screen width, which is, of course, 1080.

calc(100vw / 1px) /* 1080 */

However, if we divide that same width by 1em (and assume a font size of 16px), we get the number of em units that fit across the screen.

calc(100vw / 1em) /* 67.5 */

The resulting number is unitless in both cases, but its meaning is entirely dependent on the unit of the value we divided by.

From Length to Angle

Of course, this conversion doesn’t have to be from a type <angle> to a type <length>. Here is an example that calculates an element’s angle based on the screen width (100vw), creating a new and unusual kind of responsiveness.

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And get this: There are no media queries in here! it’s all happening in a single line of CSS doing the calculations.

To determine the angle, I first define the width range I want to work within. clamp(300px, 100vw, 700px) gives me a closed range of 400px, from 300px to 700px. I then subtract 700px from this range, which gives me a new range, from -400px to 0px.

Using typed arithmetic, I then divide this range by 400px, which gives me a normalized, unitless number between -1 and 0. And finally, I convert this number into an <angle> by multiplying it by -90deg.

Here’s what that looks like in CSS when we put it all together:

p { rotate: calc(((clamp(300px, 100vw, 700px) - 700px) / 400px) * -90deg); } From Length to Opacity

Of course, the resulting unitless number can be used as-is in any property that accepts a <number> data type, such as opacity. What if I want to determine the font’s opacity based on its size, making smaller fonts more opaque and therefore clearer? Is it possible? Absolutely.

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In this example, I am setting a different font-size value for each <p> element using a --font-size custom property. and since the range of this variable is from 0.8rem to 2rem, I first subtract 0.8rem from it to create a new range of 0 to 1.2rem.

I could divide this range by 1.2rem to get a normalized, unitless value between 0 and 1. However, because I don’t want the text to become fully transparent, I divide it by twice that amount (2.4rem). This gives me a result between 0 and 0.5, which I then subtract from the maximum opacity of 1.

p { font-size: var(--font-size, 1rem); opacity: calc(1 - (var(--font-size, 1rem) - 0.8rem) / 2.4rem); }

Notice that I am displaying the font size in pixel units even though the size is defined in rem units. I simply use typed arithmetic to divide the font size by 1px, which gives me the size in pixels as a unitless value. I then inject this value into the content of the the paragraph’s ::after pseudo-element.

p::after { counter-reset: px calc(var(--font-size, 1rem) / 1px); content: counter(px) 'px'; } Dynamic Width Colors

Of course, the real beauty of using native CSS math functions, compared to other approaches, is that everything happens dynamically at runtime. Here, for example, is a small demo where I color the element’s background relative to its rendered width.

p { --hue: calc(100cqi / 1px); background-color: hsl(var(--hue, 0) 75% 25%); }

You can drag the bottom-right corner of the element to see how the color changes in real-time.

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Here’s something neat about this demo: because the element’s default width is 50% of the screen width and the color is directly proportional to that width, it’s possible that the element will initially appear in completely different colors on different devices with different screens. Again, this is all happening without any media queries or JavaScript.

An Extreme Example: Chaining Conversions

OK, so we’ve established that typed arithmetic is cool and opens up new and exciting possibilities. Before we put a bow on this, I wanted to pit this concept against a more extreme example. I tried to imagine what would happen if we took a <length> type, converted it to a <number> type, then to an <angle> type, back to a <number> type, and, from there, back to a <length> type.

Phew!

I couldn’t find a real-world use case for such a chain, but I did wonder what would happen if we were to animate an element’s width and use that width to determine the height of something else. All the calculations might not be necessary (maybe?), but I think I found something that looks pretty cool.

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In this demo, the animation is on the solid line along the bottom. The vertical position of the ball, i.e. its height, relative to the line, is proportional to the line’s width. So, as the line expands and contracts, so does the path of the bouncing ball.

To create the parabolic arc that the ball moves along, I take the element’s width (100cqi) and, using typed arithmetic, divide it by 300px to get a unitless number between 0 and 1. I multiply that by 180deg to get an angle that I use in a sin() function (Juan Diego has a great article on this), which returns another unitless number between 0 and 1, but with a parabolic distribution of values.

Finally, I multiply this number by -200px, which outputs the ball’s vertical position relative to the line.

.ball { --translateY: calc(sin(calc(100cqi / 300px) * 180deg) * -200px) ; translate: -50% var(--translateY, 0); }

And again, because the ball’s position is relative to the line’s width, the ball’s position will remain on the same arc, no matter how we define that width.

Wrapping Up: The Dawn of Computational CSS

The ability to divide one typed value by another to produce a unitless number might seem like no big deal; more like a minor footnote in the grand history of CSS.

But as we’ve seen, this single feature is a quiet revolution. It dismantles the long-standing walls between different CSS data types, transforming them from isolated silos into a connected, interoperable system. We’ve moved beyond simple calculations, and entered the era of true Computational CSS.

This isn’t just about finding new ways to style a button or animate a loading spinner. It represents a fundamental shift in our mental model. We are no longer merely declaring static styles, but rather defining dynamic, mathematical relationships between properties. The width of an element can now intrinsically know about its color, an angle can dictate a distance, and a font’s size can determine its own visibility.

This is CSS becoming self-aware, capable of creating complex behaviors and responsive designs that adapt with a precision and elegance that previously required JavaScript.

So, the next time you find yourself reaching for JavaScript to bridge a gap between two CSS properties, pause for a moment. Ask yourself if there’s a mathematical relationship you can define instead. You might be surprised at how far you can go with just a few lines of CSS.

The Future is Calculable

The examples in this article are just the first steps into a much larger world. What happens when we start mixing these techniques with scroll-driven animations, view transitions, and other modern CSS features? The potential for creating intricate data visualizations, generative art, and truly fluid user interfaces, all natively in CSS, is immense. We are being handed a new set of creative tools, and the instruction manual is still being written.

CSS Typed Arithmetic originally published on CSS-Tricks, which is part of the DigitalOcean family. You should get the newsletter.

I’m inclined to take a few notes on Eric Bailey’s grand post about the use of inclusive personas in user research. As someone who has been in roles that have both used and created user personas, there’s so much in here

What’s the big deal, right? We’re often taught and encouraged to think about users early in the design process. It’s user’ centric design, so let’s personify 3-4 of the people we think represent our target audiences so our work is aligned with their objectives and needs. My master’s program was big on that and went deep into different approaches, strategies, and templates for documenting that research.

And, yes, it is research. The idea, in theory, is that by understanding the motivations and needs of specific users (gosh, isn’t “users” an awkward term?), we can “design backwards” so that the end goal is aligned to actions that get them there.

Eric sees holes in that process, particularly when it comes to research centered around inclusiveness. Why is that? Very good reasons that I’m compiling here so I can reference it later. There’s a lot to take in, so you’d do yourself a solid by reading Eric’s post in full. Your takeaways may be different than mine.

Traditional vs. Inclusive user research

First off, I love how Eric distinguishes what we typically refer to as the general type of user personas, like the ones I made to generalize an audience, from inclusive user personas that are based on individual experiences.

Inclusive user research practices are different than a lot of traditional user research. While there is some high-level overlap in approach, know the majority of inclusive user research is more focused on the individual experience and less about more general trends of behavior.

So, right off the bat we have to reframe what we’re talking about. There’s blanket personas that are placeholders for abstracting what we think we know about specific groups of people versus individual people that represent specific experiences that impact usability and access to content.

A primary goal in inclusive user research is often to identify concrete barriers that prevent someone from accessing the content they want or need. While the techniques people use are varied, these barriers represent insurmountable obstacles that stymie a whole host of navigation techniques and approaches.

If you’re looking for patterns, trends, and customer insights, know that what you want is regular user testing. Here, know that the same motivating factors you’re looking to uncover also exist for disabled people. This is because they’re also, you know, people.

Assistive technology is not exclusive to disabilities

It’s so easy to assume that using assistive tools automatically means accommodating a disability or impairment, but that’s not always the case. Choice points from Eric:

• First is that assistive technology is a means, and not an end.
• Some disabled people use more than one form of assistive technology, both concurrently and switching them in and out as needed.
• Some disabled people don’t use assistive technology at all.
• Not everyone who uses assistive technology has also mastered it.
• Disproportionate attention placed on one kind of assistive technology at the expense of others.
• It’s entirely possible to have a solution that is technically compliant, yet unintuitive or near-impossible to use in the actual. 

I like to keep in mind that assistive technologies are for everyone. I often think about examples in the physical world where everyone benefits from an accessibility enhancement, such as cutting curbs in sidewalks (great for skateboarders!), taking elevators (you don’t have to climb stairs in some cases), and using TV subtitles (I often have to keep the volume low for sleeping kids).

That’s the inclusive part of this. Everyone benefits rather than a specific subset of people.

Different personas, different priorities

What happens when inclusive research is documented separately from general user research?

Another folly of inclusive personas is that they’re decoupled from regular personas. This means they’re easily dismissible as considerations.

[…]

Disability is diversity, and the plain and honest truth is that diversity is missing from your personas if disability conditions are not present in at least some of them. This, in turn, means your personas are misrepresentative of the people in the abstract you claim to serve.

In practice, that means:

[…] we also want to hold space for things that need direct accessibility support and remediation when this consideration of accessibility fails to happen. It’s all about approach.

An example of how to consider your approach is when adding drag and drop support to an experience. […] [W]e want to identify if drag and drop is even needed to achieve the outcome the organization needs.

Thinking of a slick new feature that will impress your users? Great! Let’s make sure it doesn’t step on the toes of other experiences in the process, because that’s antithetical to inclusiveness. I recognize this temptation in my own work, particularly if I land on a novel UI pattern that excites me. The excitement and tickle I get from a “clever” idea gives me a blind side to evaluating the overall effectiveness of it.

Radical participatory design

Gosh dang, why didn’t my schoolwork ever cover this! I had to spend a little time reading the Cambridge University Press article explaining radical participatopry design (RPD) that Eric linked up.

Therefore, we introduce the term RPD to differentiate and represent a type of PD that is participatory to the root or core: full inclusion as equal and full members of the research and design team. Unlike other uses of the term PD, RPD is not merely interaction, a method, a way of doing a method, nor a methodology. It is a meta-methodology, or a way of doing a methodology. 

Ah, a method for methodology! We’re talking about not only including community members into the internal design process, but make them equal stakeholders as well. They get the power to make decisions, something the article’s author describes as a form of decolonization.

Or, as Eric nicely describes it:

Existing power structures are flattened and more evenly distributed with this approach.

Bonus points for surfacing the model minority theory:

The term “model minority” describes a minority group that society regards as high-performing and successful, especially when compared to other groups. The narrative paints Asian American children as high-achieving prodigies, with fathers who practice medicine, science, or law and fierce mothers who force them to work harder than their classmates and hold them to standards of perfection.

It introduces exclusiveness in the quest to pursue inclusiveness — a stereotype within a stereotype.

Thinking bigger

Eric caps things off with a great compilation of actionable takeaways for avoiding the pitfalls of inclusive user personas:

• Letting go of control leads to better outcomes.
• Member checking: letting participants review, comment on, and correct the content you’ve created based on their input.
• Take time to scrutinize the functions of our roles and how our organizations compel us to undertake them in order to be successful within them.
• Organizations can turn inwards and consider the artifacts their existing design and research processes produce. They can then identify opportunities for participants to provide additional clarity and corrections along the way.

On inclusive personas and inclusive user research originally published on CSS-Tricks, which is part of the DigitalOcean family. You should get the newsletter.

Several weeks ago, I participated in Front End Study Hall. Front End Study Hall is an HTML and CSS focused meeting held on Zoom every two weeks. It is an opportunity to learn from one another as we share our common interest in these two building blocks of the Web. Some weeks, there is more focused discussion while other weeks are more open ended and members will ask questions or bring up topics of interest.

Joe, the moderator of the group, usually starts the discussion with something he has been thinking about. In this particular meeting, he asked us about Sass. He asked us if we used it, if we liked it, and then to share our experience with it. I had planned to answer the question but the conversation drifted into another topic before I had the chance to answer. I saw it as an opportunity to write and to share some of the things that I have been thinking about recently.

Beginnings

I started using Sass in March 2012. I had been hearing about it through different things I read. I believe I heard Chris Coyier talk about it on his then-new podcast, ShopTalk Show. I had been interested in redesigning my personal website and I thought it would be a great chance to learn Sass. I bought an e-book version of Pragmatic Guide to Sass and then put what I was learning into practice as I built a new version of my website. The book suggested using Compass to process my Sass into CSS. I chose to use SCSS syntax instead of indented syntax because SCSS was similar to plain CSS. I thought it was important to stay close to the CSS syntax because I might not always have the chance to use Sass, and I wanted to continue to build my CSS skills.

It was very easy to get up and running with Sass. I used a GUI tool called Scout to run Compass. After some frustration trying to update Ruby on my computer, Scout gave me an environment to get up and going quickly. I didn’t even have to use the command line. I just pressed “Play” to tell my computer to watch my files. Later I learned how to use Compass through the command line. I liked the simplicity of that tool and wish that at least one of today’s build tools incorporated that same simplicity.

I enjoyed using Sass out of the gate. I liked that I was able to create reusable variables in my code. I could set up colors and typography and have consistency across my code. I had not planned on using nesting much but after I tried it, I was hooked. I really liked that I could write less code and manage all the relationships with nesting. It was great to be able to nest a media query inside a selector and not have to hunt for it in another place in my code.

Fast-forward a bit…

After my successful first experience using Sass in a personal project, I decided to start using it in my professional work. And I encouraged my teammates to embrace it. One of the things I liked most about Sass was that you could use as little or as much as you liked. I was still writing CSS but now had the superpower that the different helper functions in Sass enabled.

I did not get as deep into Sass as I could have. I used the Sass @extend rule more in the beginning. There are a lot of features that I did not take advantage of, like placeholder selectors and for loops. I have never been one to rely much on shortcuts. I use very few of the shortcuts on my Mac. I have dabbled in things like Emmet but tend to quickly abandon them because I am just use to writing things out and have not developed the muscle memory of using shortcuts.

Is it time to un-Sass?

By my count, I have been using Sass for over 13 years. I chose Sass over Less.js because I thought it was a better direction to go at the time. And my bet paid off. That is one of the difficult things about working in the technical space. There are a lot of good tools but some end up rising to the top and others fall away. I have been pretty fortunate that most of the decisions I have made have gone the way that they have. All the agencies I have worked for have used Sass.

At the beginning of this year, I finally jumped into building a prototype for a personal project that I have been thinking about for years: my own memory keeper. One of the few things that I liked about Facebook was the Memories feature. I enjoyed visiting that page each day to remember what I had been doing on that specific day in years past. But I felt at times that Facebook was not giving me all of my memories. And my life doesn’t just happen on Facebook. I also wanted a way to view memories from other days besides just the current date.

As I started building my prototype, I wanted to keep it simple. I didn’t want to have to set up any build tools. I decided to write CSS without Sass.

Okay, so that was my intention. But I soon realized that that I was using nesting. I had been working on it a couple of days before I realized it.

But my code was working. That is when I realized that the native nesting in CSS works much the same nesting in Sass. I had followed the discussion about implementing nesting in native CSS. At one point, the syntax was going to be very different. To be honest, I lost track of where things had landed because I was continuing to use Sass. Native CSS nesting was not a big concern to me right then.

I was amazed when I realized that nesting works just the same way. And it was in that moment that I began to wonder:

Is this finally the time to un-Sass?

I want to give credit where credit is due. I’m borrowing the term “un-Sass” from Stu Robson, who is actually in the middle of writing a series called “Un-Sass’ing my CSS” as I started thinking about writing this post. I love the term “un-Sass” because it is easy to remember and so spot on to describe what I have been thinking about.

Here is what I am taking into consideration:

Custom Properties

I knew that a lot about what I liked about Sass had started to make its way into native CSS. Custom properties were one of the first things. Custom properties are more powerful than Sass variables because you can assign a new value to a custom property in a media query or in a theming system, like light and dark modes. That’s something Sass is unable to do since variables become static once they are compiled into vanilla CSS. You can also assign and update custom properties with JavaScript. Custom properties also work with inheritance and have a broader scope than Sass variables.

So, yeah. I found that not only was I already fairly familiar with the concept of variables, thanks to Sass, but the native CSS version was much more powerful.

I first used CSS Custom Properties when building two different themes (light and dark) for a client project. I also used them several times with JavaScript and liked how it gave me new possibilities for using CSS and JavaScript together. In my new job, we use custom properties extensively and I have completely switched over to using them in any new code that I write. I made use of custom properties extensively when I redesigned my personal site last year. I took advantage of it to create a light and dark theme and I utilized it with Utopia for typography and spacing utilities.

Nesting

When Sass introduced nesting, it simplified the writing of CSS code because you write style rules within another style rule (usually a parent). This means that you no longer had to write out the full descendent selector as a separate rule. You could also nest media queries, feature queries, and container queries.

This ability to group code together made it easier to see the relationships between parent and child selectors. It was also useful to have the media queries, container queries, or feature queries grouped inside those selectors rather than grouping all the media query rules together further down in the stylesheet.

I already mentioned that I stumbled across native CSS nesting when writing code for my memory keeper prototype. I was very excited that the specification extended what I already knew about nesting from Sass.

Two years ago, the nesting specification was going to require you to start the nested query with the & symbol, which was different from how it worked in Sass.

.footer { a { color: blue } } /* 2023 */ .footer { & a { color: blue } /* This was valid then */ }

But that changed sometime in the last two years and you no longer need the ampersand (&) symbol to write a nested query. You can write just as you had been writing it in Sass. I am very happy about this change because it means native CSS nesting is just like I have been writing it in Sass.

/* 2025 */ .footer { a { color: blue } /* Today's valid syntax */ }

There are some differences in the native implementation of nesting versus Sass. One difference is that you cannot create concatenated selectors with CSS. If you love BEM, then you probably made use of this feature in Sass. But it does not work in native CSS.

.card { &__title {} &__body {} &__footer {} }

It does not work because the & symbol is a live object in native CSS and it is always treated as a separate selector. Don’t worry, if you don’t understand that, neither do I. The important thing is to understand the implication – you cannot concatenate selectors in native CSS nesting.

If you are interested in reading a bit more about this, I would suggest Kevin Powell’s, “Native CSS Nesting vs. Sass Nesting” from 2023. Just know that the information about having to use the & symbol before an element selector in native CSS nesting is out of date.

I never took advantage of concatenated selectors in my Sass code so this will not have an impact on my work. For me, nesting is native CSS is equivalent to how I was using it in Sass and is one of the reasons why to consider un-Sassing.

My advice is to be careful with nesting. I would suggest trying to keep your nested code to three levels at the most. Otherwise, you end up with very long selectors that may be more difficult to override in other places in our codebase. Keep it simple.

The color-mix() function

I liked using the Sass color module to lighten or darken a color. I would use this most often with buttons where I wanted the hover color to be different. It was really easy to do with Sass. (I am using $color to stand in for the color value).

background-color: darken($color, 20%);

The color-mix() function in native CSS allows me to do the same thing and I have used it extensively in the past few months since learning about it from Chris Ferdinandi.

background-color: color-mix(in oklab, var(--color), #000000 20%); Mixins and functions

I know that a lot of developers who use Sass make extensive use of mixins. In the past, I used a fair number of mixins. But a lot of the time, I was just pasting mixins from previous projects. And many times, I didn’t make as much use of them as I could because I would just plain forget that I had them. They were always nice helper functions and allowed me to not have to remember things like clearfix or font smoothing. But those were also techniques that I found myself using less and less.

I also utilized functions in Sass and created several of my own, mostly to do some math on the fly. I mainly used them to convert pixels into ems because I liked being able to define my typography and spacing as relative and creating relationships in my code. I also had written a function to covert pixels to ems for custom media queries that did not fit within the breakpoints I normally used. I had learned that it was a much better practice to use ems in media queries so that layouts would not break when a user used page zoom.

Currently, we do not have a way to do mixins and functions in native CSS. But there is work being done to add that functionality. Geoff wrote about the CSS Functions and Mixins Module.

I did a little experiment for the use case I was using Sass functions for. I wanted to calculate em units from pixels in a custom media query. My standard practice is to set the body text size to 100% which equals 16 pixels by default. So, I wrote a calc() function to see if I could replicate what my Sass function provided me.

@media (min-width: calc((600 / 16) * 1em));

This custom media query is for a minimum width of 600px. This would work based on my setting the base font size to 100%. It could be modified.

Tired of tooling

Another reason to consider un-Sassing is that I am simply tired of tooling. Tooling has gotten more and more complex over the years, and not necessarily with a better developer experience. From what I have observed, today’s tooling is predominantly geared towards JavaScript-first developers, or anyone using a framework like React. All I need is a tool that is easy to set up and maintain. I don’t want to have to learn a complex system in order to do very simple tasks.

Another issue is dependencies. At my current job, I needed to add some new content and styles to an older WordPress site that had not been updated in several years. The site used Sass, and after a bit of digging, I discovered that the previous developer had used CodeKit to process the code. I renewed my Codekit license so that I could add CSS to style the content I was adding. It took me a bit to get the settings correct because the settings in the repo were not saving the processed files to the correct location.

Once I finally got that set, I continued to encounter errors. Dart Sass, the engine that powers Sass, introduced changes to the syntax that broke the existing code. I started refactoring a large amount of code to update the site to the correct syntax, allowing me to write new code that would be processed. 

I spent about 10 minutes attempting to refactor the older code, but was still getting errors. I just needed to add a few lines of CSS to style the new content I was adding to the site. So, I decided to go rogue and write the new CSS I needed directly in the WordPress template. I have had similar experiences with other legacy codebases, and that’s the sort of thing that can happen when you’re super reliant on third-party dependencies. You spend more time trying to refactor the Sass code so you can get to the point where you can add new code and have it compiled.

All of this has left me tired of tooling. I am fortune enough at my new position that the tooling is all set up through the Django CMS. But even with that system, I have run into issues. For example, I tried using a mixture of percentage and pixels values in a minmax() function and Sass was trying to evaluate it as a math function and the units were incompatible.

grid-template-columns: repeat(auto-fill, minmax(min(200px, 100%), 1fr));

I needed to be able to escape and not have Sass try to evaluate the code as a math function:

grid-template-columns: repeat(auto-fill, minmax(unquote("min(200px, 100%)"), 1fr));

This is not a huge pain point but it was something that I had to take some time to investigate that I could have been using to write HTML or CSS. Thankfully, that is something Ana Tudor has written about.

All of these different pain points lead me to be tired of having to mess with tooling. It is another reason why I have considered un-Sassing.

Verdict

So what is my verdict — is it time to un-Sass?

Please don’t hate me, but my conclusion is: it depends. Maybe not the definitive answer you were looking for.

But you probably are not surprised. If you have been working in web development even a short amount of time, you know that there are very few definitive ways of doing things. There are a lot of different approaches, and just because someone else solves it differently, does not mean you are right and they are wrong (or vice versa). Most things come down to the project you are working on, your audience, and a host of other factors.

For my personal site, yes, I would like to un-Sass. I want to kick the build process to the curb and eliminate those dependencies. I would also like for other developers to be able to view source on my CSS. You can’t view source on Sass. And part of the reason I write on my site is to share solutions that might benefit others, and making code more accessible is a nice maintenance enhancement.

My personal site does not have a very large codebase. I could probably easily un-Sass it in a couple of days or over a weekend.

But for larger sites, like the codebase I work with at my job. I wouldn’t suggest un-Sassing it. There is way too much code that would have to be refactored and I am unable to justify the cost for that kind of effort. And honestly, it is not something I feel motivated to tackle. It works just fine the way that it is. And Sass is still a very good tool to use. It’s not “breaking” anything.

Your project may be different and there might be more gains from un-Sassing than the project I work on. Again, it depends.

The way forward

It is an exciting time to be a CSS developer. The language is continuing to evolve and mature. And every day, it is incorporating new features that first came to us through other third-party tools such as Sass. It is always a good idea to stop and re-evaluate your technology decisions to determine if they still hold up or if more modern approaches would be a better way forward.

That does not mean we have to go back and “fix” all of our old projects. And it might not mean doing a complete overhaul. A lot of newer techniques can live side by side with the older ones. We have a mix of both Sass variables and CSS custom properties in our codebase. They don’t work against each other. The great thing about web technologies is that they build on each other and there is usually backward compatibility.

Don’t be afraid to try new things. And don’t judge your past work based on what you know today. You did the best you could given your skill level, the constraints of the project, and the technologies you had available. You can start to incorporate newer ways right alongside the old ones. Just build websites!

Is it Time to Un-Sass? originally published on CSS-Tricks, which is part of the DigitalOcean family. You should get the newsletter.