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css module

CSS scroll-driven animations

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The CSS scroll-driven animations module provides functionality that builds on the CSS animations module and Web Animations API. It allows you to animate property values along a scroll-based timeline rather than the default time-based document timeline. This means that you can animate an element by scrolling the element, its scroll container, or its root element, rather than just by the passing of time.

Scroll-driven animations in action

You can define the scroller that controls the animation either by naming the animation or with the scroll() function.

<main>
  <div></div>
</main>

main {
  scroll-timeline: --main-timeline;
}

div {
  animation: background-animation linear;
  animation-timeline: scroll(nearest inline);
}

div::after {
  animation: shape-animation linear;
  animation-timeline: --main-timeline;
}

@layer animations {
  @keyframes background-animation {
    0% {
      background-color: palegoldenrod;
    }
    100% {
      background-color: magenta;
    }
  }
  @keyframes shape-animation {
    0% {
      left: 0;
      top: 0;
      background-color: black;
    }
    50% {
      top: calc(100% - var(--elSize));
      left: calc(50% - var(--elSize));
      background-color: red;
    }
    100% {
      left: calc(100vw - var(--elSize));
      top: 0;
      rotate: 1800deg;
      background-color: white;
    }
  }
}

@layer page-setup {
  :root {
    --elSize: 50px;
  }
  main {
    height: 90vh;
    overflow: scroll;
    border: 1px solid;
    margin: 5vh auto;
  }
  div {
    height: 400vh;
    width: 400vw;
  }
  div::after {
    content: "";
    border: 1px solid red;
    height: var(--elSize);
    width: var(--elSize);
    position: absolute;
    border-radius: 20px;
    corner-shape: superellipse(-4);
  }
}

@layer no-support {
  @supports not (scroll-timeline: --main-timeline) {
    body::before {
      content: "Your browser doesn't support scroll-driven animations.";
      background-color: wheat;
      display: block;
      text-align: center;
      padding: 1rem 0;
    }
  }
}
Interactive exampleOpen the canonical MDN source to run this embedded demo.

Scroll the element in the inline direction to see its background color change. Scroll it vertically to see the generated content move, spin, and change colors.

Reference

Properties

Data types and values

Functions

Interfaces

Guides

Specifications

SpecificationsStandards references are available on the canonical MDN page.

See also