布局特点：
顶部固定、导航菜单固定、底部永远处于页面底部。
代码如下：
<!DOCTYPE html>
<html>
<head>
<title></title>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8"/>
<style type="text/css">
html, body
{
padding:0;
margin:0;
height:100%;
position:relative;
}
#divHeader
{
background-color:rgba(200,200,200,0.95);
*background-color:#ddd;
position:fixed;
100%;
height:50px;
top:0px;
outline:solid 5px rgba(200,200,200,0.6);
}
#divMain
{
padding-top:60px;
padding-bottom:60px;
padding-left:100px;
background-color:white;
_padding-top:10px;
_padding-bottom:10px;
}
#divFooter
{
background-color:#ddd;
position:absolute;
100%;
height:50px;
bottom:0px;
_position:;
}
#divNav
{
90px; position:fixed; left:0px; top:60px; bottom:60px; overflow:auto;
_position:absolute;
}
#divNav a
{
display:block;
padding:3px;
margin:0 3px;
background-color:#eee;
}
#divNav a:hover
{
background-color:#aaa;
}
</style>
<script type="text/javascript">
function addContent()
{
for (var i = 0; i < 10; i++)
{
document.getElementById('divMain').innerHTML += 'CONTENT<br />';
}
}
function resetContent()
{
document.getElementById('divMain').innerHTML = '';
}
</script>
</head>
<body style="background-color:#fff;">
<div style="position:relative; min-height:100%;">
<div id="divNav">
<a href="#">菜单1</a>
<a href="#">菜单1</a>
<a href="#">菜单1</a>
<a href="#">菜单1</a>
<a href="#">菜单1</a>
<a href="#">菜单1</a>
<a href="#">菜单1</a>
<a href="#">菜单1</a>
<a href="#">菜单1</a>
<a href="#">菜单1</a>
</div>
<div id="divHeader">
divHeader
<input type="button" value="add content" onclick="addContent();" />
<input type="button" value="reset content" onclick="resetContent();" />
</div>
<div id="divMain">
CONTENT<br />
CONTENT<br />
CONTENT<br />
CONTENT<br />
CONTENT<br />
CONTENT<br />
CONTENT<br />
CONTENT<br />
CONTENT<br />
CONTENT<br />
CONTENT<br />
CONTENT<br />
CONTENT<br />
CONTENT<br />
CONTENT<br />
CONTENT<br />
CONTENT<br />
CONTENT<br />
CONTENT<br />
CONTENT<br />
CONTENT<br />
CONTENT<br />
CONTENT<br />
CONTENT<br />
CONTENT<br />
CONTENT<br />
CONTENT<br />
CONTENT<br />
CONTENT<br />
CONTENT<br />
CONTENT<br />
CONTENT<br />
<div>
haha
</div>
</div>
<div id="divFooter">
divFooter<br />
divFooter<br />
</div>
</div>
</body>
</html>