Scroll-Driven Animations Inside a CSS Carousel

I was reflecting on what I learned about CSS Carousels recently. There’s a lot they can do right out of the box (and some things they don’t) once you define a scroll container and hide the overflow.

Hey, isn’t there another fairly new CSS feature that works with scroll regions? Oh yes, that’s Scroll-Driven Animations. Shouldn’t that mean we can trigger an animation while scrolling through the items in a CSS carousel?

Why yes, that’s exactly what it means. At least in Chrome at the time I’m playing with this:

It’s as straightforward as you might expect: define your keyframes and apply them on the carousel items:

@keyframes foo {
  from {
    height: 0;
  }
  to {
    height: 100%;
    font-size: calc(2vw + 1em);
  }
}

.carousel li {
  animation: foo linear both;
  animation-timeline: scroll(inline);
}

There are more clever ways to animate these things of course. But what’s interesting to me is that this demo now combines CSS Carousels with Scroll-Driven Animations. The only rub is that the demo also slaps CSS Scroll Snapping in there with smooth scrolling, which is effectively wiped out when applying the scroll animation.

I thought I might work around that with a view() timeline instead. That certainly makes for a smoother animation that is applied to each carousel item as they scroll into view, but no dice on smooth scrolling.