scroll-timeline-axis

Limited availability

This feature is not Baseline because it does not work in some of the most widely-used browsers.

The scroll-timeline-axis CSS property is used to specify the scrollbar direction that will be used to provide the timeline for a scroll driven animation animation, which is progressed through by scrolling a scrollable element (scroller).

Syntax

css

/* Logical property values */
scroll-timeline-axis: block;
scroll-timeline-axis: inline;

/* Physical property values */
scroll-timeline-axis: y;
scroll-timeline-axis: x;

/* Global values */
scroll-timeline-axis: inherit;
scroll-timeline-axis: initial;
scroll-timeline-axis: revert;
scroll-timeline-axis: revert-layer;
scroll-timeline-axis: unset;

Values

<axis>: An <axis> keyword value describing the direction, or axis, of the scrollport that controls the scroll-driven animation. The default value is block.

Description

The scroll-timeline-axis property specifies which scrollbar will be used to provide the timeline for a scroll progress timeline animation. The value is the <axis> of the scrollbar. The scroll-timeline property is set on the scroller that will provide the timeline.

If the scroller element does not overflow its container in the axis dimension or if the overflow is hidden or clipped, no scroll progress timeline will be created.

The scroll-timeline-axis and scroll-timeline-name properties can also be set using the scroll-timeline shorthand property.

Formal definition

Initial value	`block`
Applies to	scroll containers
Inherited	no
Computed value	as specified
Animation type	Not animatable

Formal syntax

scroll-timeline-axis = 
  [ block | inline | x | y ]#

Examples

Defining the axis of the scroll progress timeline

In this example, a scroll progress timeline named --my-scroller is defined using the scroll-timeline-name property on the :root element (<html>). This timeline is then applied to the animation on the element with the animation class using animation-timeline: --my-scroller.

To demonstrate the effect of scroll-timeline-axis, a horizontal (non-default) scrollbar is used in this example to drive the animation.

HTML

The HTML for the example is shown below.

html

<body>
  <div class="content"></div>
  <div class="box animation"></div>
</body>

CSS

The CSS for the container sets the :root as the source of a scroll progress timeline named --my-scroller using the scroll-timeline-name property. The scroll axis is set using scroll-timeline-axis: x; which causes the horizontal scrollbar position to determine the animation timeline. We also include scroll-timeline-axis: horizontal; for browsers that support the non-standard legacy horizontal and vertical values and not x and y.

The width of the .content element is set to a large value to make it overflow the :root element.

The .animation element has the animation applied to it using the animation shorthand, and the scroll timeline set using the animation-timeline.

css

:root {
  scroll-timeline-name: --my-scroller;

  scroll-timeline-axis: x;
  scroll-timeline-axis: horizontal;
}

body {
  margin: 0;
  overflow-y: hidden;
}

.content {
  height: 100vh;
  width: 2000px;
}

.box {
  width: 100px;
  height: 100px;
  border-radius: 10px;
  background-color: rebeccapurple;
  position: fixed;
  top: 25px;
  left: 25px;
}

.animation {
  animation: rotate-appear 1ms linear;
  animation-timeline: --my-scroller;
}

@keyframes rotate-appear {
  from {
    rotate: 0deg;
    top: 0%;
  }

  to {
    rotate: 720deg;
    top: 100%;
  }
}

@layer no-support {
  @supports not (scroll-timeline-axis: block) {
    body::before {
      content: "Your browser doesn't support the `scroll-timeline-axis` property.";
      background-color: wheat;
      display: block;
      width: 100%;
      text-align: center;
    }
  }
}