尝试一下》

          <!DOCTYPE html>
<html>
<head>
  <meta charset="utf-8">
  <style>
    #myDIV {
      width: 300px;
      height: 200px;
      border: 1px solid black;
      background-image: url("/examples/smiley.gif");
      background-position: top left;
      -webkit-animation: mymove 5s infinite;
      /* Chrome, Safari, Opera */
      animation: mymove 5s infinite;
    }
    /* Chrome, Safari, Opera */

    @-webkit-keyframes mymove {
      50% {
        background-position: center;
      }
    }
    /* Standard syntax */

    @keyframes mymove {
      50% {
        background-position: center;
      }
    }
  </style>
</head>
<body>

  <p>逐步改变 background-position 属性，从 "top left" 到 "center",然后回到 "top left":
    <p>
      <div id="myDIV"></div>
      <p>background-position 属性支持动画效果。</p>
      <p><b>注意：</b>Internet Explorer 9 及更早 IE 版本不支持 CSS 动画。</p>

</body>
</html>
        
尝试一下 》
