jquery实现的tab选项卡

<ul class="nav">
    <li class="on">选项卡1</li>
    <li>选项卡2</li>
    <li>选项卡3</li>
    <li>选项卡4</li>
</ul>
<ul class="con">
    <li class="active">1</li>
    <li>2</li>
    <li>3</li>
    <li>4</li>
</ul>

   ul,li{
            margin: 0;
            padding: 0;
        }
        li{
            float: left;
            list-style: none;
            text-align: center;
        }
        .nav{
            width: 400px;
            height: 50px;
        }
        .nav li{
            width: 100px;
            height: 50px;
            line-height: 50px;

        }
       .on{
           background-color:red;
       }
        .con{
            width: 400px;
            height: 300px;
            border: 1px solid black;
            position: relative;
        }
        .con li{
            width: 400px;
            height: 300px;
            line-height: 300px;
            font-size: 50px;
            position: absolute; /**************不写left和top值默认为0***************/
            display: none;
        }
        .con li.active{
            display: block;
        }

   $(function(){
            $(".nav li").mouseover(function(){
                $(this).addClass("on").siblings().removeClass("on");
               var index= $(this).index();
                $(".con li").eq(index).addClass("active").siblings().removeClass("active");
            })
        })