chromium/third_party/blink/web_tests/external/wpt/css/css-transitions/transition-property-045-manual.html

<!DOCTYPE html>
<meta charset="utf-8">
<title>CSS Transitions Test: transition-property - z-index</title>
<link rel="author" title="Intel" href="http://www.intel.com">
<link rel="author" title="Shiyou Tan" href="mailto:[email protected]">
<link rel="help" href="https://drafts.csswg.org/web-animations-1/#animation-type">
<link rel="help" href="https://www.w3.org/TR/CSS22/visuren.html#z-index">
<meta name="flags" content="ahem">
<meta name="assert" content="Test checks that the 'z-index' property is animatable.">
<style>
  div {
    height: 100px;
    width: 100px;
  }
  #ref {
    background-color: red;
    z-index: 1;
  }
  #test {
    background-color: green;
    position: relative;
    top: -100px;
    transition-duration: 2s;
    transition-property: z-index;
    transition-timing-function: linear;
    z-index: -100;
  }
</style>
<body>
  <p>Click red square below. Test passes if the color of square changes to green after waiting a moment.</p>
  <div id="ref"></div>
  <div id="test"></div>
  <script>
    (function() {
      var test = document.querySelector("#test");
      document.addEventListener("click", function(evt) {
        test.setAttribute("style", "z-index: 100;");
      }, false);
    })();
  </script>
</body>