html运行实例（css3_animation

代码示例：（标识：css3_animation_2）

<!DOCTYPE html>
<html>
<head>
<style>
div {
  width: 100px;
  height: 100px;
  background-color: red;
  animation-name: example;
  animation-duration: 4s;
}

@keyframes example {
  0%   {background-color: red;}
  25%  {background-color: yellow;}
  50%  {background-color: blue;}
  100% {background-color: green;}
}
</style>
</head>
<body>

<p><b>注释：</b>本例在 Internet Explorer 9 以及更早的版本中无效。</p>

<div></div>

</body>
</html>