css-animations-1/animation-play-state-001.html

<!DOCTYPE html>
<meta charset="utf-8">
<title>CSS Animations Test: animation-play-state - paused</title>
<link rel="author" title="Nokia Inc." href="http://www.nokia.com">
<link rel="author" title="Intel" href="http://www.intel.com">
<link rel="reviewer" title="Zhiqiang Zhang" href="mailto:zhiqiang.zhang@intel.com"> <!-- 2015-05-07 -->
<link rel="help" href="https://drafts.csswg.org/css-animations-1/#animation-name">
<link rel="help" href="https://drafts.csswg.org/css-animations-1/#animation-duration">
<link rel="help" href="https://drafts.csswg.org/css-animations-1/#animation-play-state">
<meta name="flags" content="animated">
<meta name="assert" content="When animation-play-state is set to paused,
                             animation is paused where the progress it had made
                             before being paused.">
<style>
  #test-animation-paused {
    animation-name: sample;
    animation-duration: 10s;

    background-color: blue;
    height: 100px;
    width: 100px;
    position: relative;
  }

  #ref-path {
    background-color: yellow;
    height: 10px;
    width: 250px;
    position: relative;
  }

  @keyframes sample {
    from {
      left: 150px;
    }
    to {
      left: 0px;
    }
  }
</style>
<body>
  <p>
    Test passes if there is a filled blue square with 'Filler Text',
    which starts moving right to left along the yellow bar,
    and pauses in the middle after about 2 seconds' animation.
  </p>
  <div id="test-animation-paused">Filler Text</div>
  <div id="ref-path"></div>
  <script>
    setTimeout(setAnimationRunning, 2000);

    function setAnimationRunning() {
      var div = document.getElementsByTagName("div");
      div[0].style.animationPlayState = "paused";
    }
  </script>
</body>