<meta charset="utf-8" /> <title>ajax test</title> <script type="text/javascript" src="http://code.jquery.com/jquery-latest.js"></script> <style type="text/css"> ul{ 100%; height: auto;} ul li{ float: left; 30%; height: 30px; background: beige;} .blue{ background-color: #e3f7f8;} .red{ background: red;} .yeow{ background: yellow;} .now{ background: #7cc7ff;} </style> <script src="http://www.gmodules.com/ig/ifr?url=http://www.google.com/ig/modules/translatemypage.xml&up_source_language=zh-CN&w=160&h=60&title=&border=&output=js"></script> </head> <body> <ul> <li class="blue"> <a href=" ">积木系列</a> </li> <li class="red"> <a href="#">过家家系列</a> </li> <li class="yeow"> <a href="#">女孩系列</a> </li> </ul> <script> $("li").click(function(){ index=$(this).index(); $("li").eq(index).addClass("now").siblings().removeClass("now"); }) </script> </body> </html>