<!DOCTYPE html>
<html lang="en">
<head>
<style type="text/css">
#header,
#nav,
#content-main,
#content-2,
#content-3,
#content-4,
#content-5,
#content-6,
#footer {
width: 960px;
background-color: #eee;
border: 1px dashed #ccc;
margin: 0 auto;
height: 500px;
margin-bottom: 5px;
}
#header,
#header>.inner {
height: 120px;
border-width: 0;
}
/*顶部宽度需要设置成100%*/
#header {
width: 100%;
}
/*中间部分宽度需与导航栏、内容部分宽度保持一致，并且水平居中*/
#header>.inner {
width: 960px;
/*margin是无法继承的，所以要单独设置*/
margin: 0 auto;
}
#nav {
height: 80px;
}
#content-main>.left,
#content-main>.right {
height: 500px;
background-color: #f00;
border: 1px solid #000;
float: left;
}
#content-main>.left {
width: 318px;
}
#content-main>.right {
width: 628px;
float: right;
}
#footer,
#footer>.inner {
height: 100px;
border-width: 0;
}
/*底部宽度需要设置成100%*/
#footer {
width: 100%;
margin-bottom: 0;
}
/*中间部分宽度需与导航栏、内容部分宽度保持一致，并且水平居中*/
#footer>.inner {
width: 960px;
/*margin是无法继承的，所以要单独设置*/
margin: 0 auto;
}
</style>
</head>
<body>
<div id="header">
<div class="inner">header-inner</div>
</div>
<div id="nav">nav</div>
<div id="content-main">
<div class="left">left</div>
<div class="right">right</div>
</div>
<div id="content-2">content-2</div>
<div id="content-2">content-3</div>
<div id="content-2">content-4</div>
<div id="content-2">content-5</div>
<div id="content-2">content-6</div>
<div id="footer">
<div class="inner">footer-inner</div>
</div>
</body>
</html>