chromium/third_party/blink/web_tests/external/wpt/css/css-animations/animation-delay-008.html

<!doctype html>
<html class="reftest-wait">
<meta charset="utf-8">
<title>CSS Animations Test: animation-delay - liveness</title>
<link rel="author" title="Brian Birtles" href="mailto:[email protected]">
<link rel="help" href="https://drafts.csswg.org/css-animations-1/#animations">
<meta name="assert" content="Check that changes to animation-delay on a running
animation are reflected in output">
<meta name="flags" content="dom">
<link rel="match" href="animation-common-ref.html">
<style>
@keyframes two-step {
  from { background-color: red }
  50% { background-color: green }
  to { background-color: green }
}
div {
  width: 100px;
  height: 100px;
  background-color: orange;
}
</style>
<div></div>
<script>
// Set up animation with no delay
var div = document.querySelector('div');
div.style.animation = 'two-step 200s steps(1)';
window.getComputedStyle(div).animation;

// Wait until animation has started and change delay
window.requestAnimationFrame(function() {
  // Fast-forward to mid-point
  div.style.animationDelay = '-100s';
  document.documentElement.removeAttribute('class');
});
</script>
</html>