<!DOCTYPE html>
<meta charset="utf-8">
<title>CSS Transitions Test: transition-duration - negative number</title>
<link rel="author" title="Intel" href="http://www.intel.com">
<link rel="author" title="Shiyou Tan" href="mailto:shiyoux.tan@intel.com">
<link rel="help" title="2.2. The 'transition-duration' Property" href="http://www.w3.org/TR/css3-transitions/#transition-duration-property">
<meta name="assert" content="A negative value for 'transition-duration renders the declaration invalid which means the transition is immediate.">
<style>
  div {
    height: 100px;
    transition-property: width;
    transition-timing-function: linear;
    width: 100px;
  }
  #ref {
    background-color: yellow;
    transition-duration: 2s;
  }
  #test {
    background-color: blue;
    transition-duration: -2s;
  }
</style>
<body>
  <p>Click the 'Start' button below. Test passes if the width of yellow square grows smoothly but the blue grows immediately.</p>
  <div id="ref"></div>
  <div id="test"></div>
  <button>Start</button>
  <script>
    (function() {
      var button = document.querySelector("button"),
          test = document.querySelector("#test"),
          ref = document.querySelector("#ref");
      button.addEventListener("click", function(evt) {
        test.setAttribute("style", "width: 200px;");
        ref.setAttribute("style", "width: 200px;");
      }, false);
    })();
  </script>
</body>