摘要：
字符集=gb2312“/>；边距；填充；}.中间｛边距；}.页脚｛空白；清除；背景色；顶部<；divclass=“middle”>；中间<；div class=“both”>；整行<；左侧<；divclass=“center”>；
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd";><html xmlns="http://www.w3.org/1999/xhtml"; lang="gb2312">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=gb2312" />
<title>上中下三行三列结构的Div布局</title>
<style>
body{text-align:center;margin:0;padding:0}
div
{
height:200px;
}
.title
{
margin:0 auto;
776px;
background-color:#abcdef;
}
.middle
{
margin:0 auto;
776px;
}
.left
{
float:left;
clear:right;
20%;
background-color:#eeefff;
}
.center
{
float:left;
clear:right;
50%;
background-color:#CCC000;
}
.right
{
float:left;
clear:right;
30%;
background-color:#fff000;
}
.both
{
clear:both;
100%;
background-color:#666999;
}
.footer
{
margin:0 auto;
776px;
clear:both;
background-color:#000fff;
}
</style>
</head>
<body>
<div class="title">顶部</div>
<div class="middle">
<div class="left">左侧</div>
<div class="center">中部</div>
<div class="right">右侧</div>
<div class="both">全行</div>
<div class="left">左侧</div>
<div class="center">中部</div>
<div class="right">右侧</div>
<div class="both">全行</div>
<div class="left">左侧</div>
<div class="center">中侧</div>
<div class="right">右侧</div>
</div>
<div class="footer">底部</div>
</body>
</html>