代码如下：
<html><head>
<style type="text/css">
*
{
padding-bottom: 0px
margin: 0px
padding-left: 0px
padding-right: 0px
font-size: 12px
padding-top: 0px
}
BODY
{
padding-left: 20px
padding-top: 20px
}
.wid240
{
width: 242px
margin-bottom: 20px
}
.wid180
{
width: 182px
}
.tab
{
border-bottom: #000 1px solid
border-left: #000 1px solid
border-top: #000 1px solid
border-right: #000 1px solid
}
.tab UL
{
zoom: 1
clear: both
}
.tab UL:after
{
display: block
height: 0px
visibility: hidden
clear: both
content: ""
}
.tab UL LI
{
text-align: center
line-height: 26px
width: 60px
display: inline
background: #000
float: left
height: 26px
color: #fff
}
.tab UL LI.on
{
background: #fff
color: #000
}
.tabList
{
border-bottom: #000 1px solid
border-left: #000 1px solid
height: 150px
border-top: #000 1px
border-right: #000 1px solid
}
.tabList .one
{
padding-bottom: 10px
padding-left: 10px
padding-right: 10px
display: none
color: #ff0000
padding-top: 10px
}
.tabList .block
{
display: block
}
</style>
<script type="text/javascript">
function setTab(name,m,n){
for( var i=1i<=ni++){
var menu = document.getElementById(name+i)
var showDiv = document.getElementById("cont_"+name+"_"+i)
menu.className = i==m ?"on":""
showDiv.style.display = i==m?"block":"none"
}
}
</script>
<meta name="GENERATOR" content="MSHTML 8.00.7600.16535">
</head>
<body>
<div class="wid240">
<div class="tab">
<ul>
<li id="one1" class="on" onmouseover='setTab("one",1,4)'>one1 </li>
<li id="one2" onmouseover='setTab("one",2,4)'>one2 </li>
<li id="one3" onmouseover='setTab("one",3,4)'>one3 </li>
<li id="one4" onmouseover='setTab("one",4,4)'>one4 </li>
</ul>
</div>
<div class="tabList">
<div id="cont_one_1" class="one block">
cont_one_1</div>
<div id="cont_one_2" class="one">
cont_one_2</div>
<div id="cont_one_3" class="one">
cont_one_3</div>
<div id="cont_one_4" class="one">
cont_one_4</div>
</div>
</div>
<div class="wid180">
<div class="tab">
<ul>
<li id="tow1" class="on" onclick='setTab("tow",1,3)'>tow1 </li>
<li id="tow2" onclick='setTab("tow",2,3)'>tow2 </li>
<li id="tow3" onclick='setTab("tow",3,3)'>tow3 </li>
</ul>
</div>
<div class="tabList">
<div id="cont_tow_1" class="one block">
cont_tow_1</div>
<div id="cont_tow_2" class="one">
cont_tow_2</div>
<div id="cont_tow_3" class="one">
cont_tow_3</div>
</div>
</div>
</body>
</html>
直接复制到本地html页面运行就可以，望采纳，谢谢！
按你的思路改的话，js部分至少还需要自己实现getElementsByClassName()方法和类似jQuery的children()方法才能实现。现在流行的js库一般都有现成的tab效果，jQuery ui的tab效果参见：
http://jqueryui.com/demos/tabs/
