CSS基础篇--可扩展性的页面布局

1.左右结构，左边100%；右边宽度固定

css代码：

<style>
#header{height:80px; background:#CCC;}
#center{overflow:hidden; zoom:1;}
#main_wrapper{float:left; width:100%; margin-top:10px; margin-left:-210px;}
#main{height:200px; margin-left:210px; background:#999;}
#sidebar{float:right; width:200px; margin-top:10px; height:200px; background:#AAA;}
#footer{height:50px; margin-top:10px; background:#CCC;}
</style>

HTML代码:

<div id="header"></div>
<div id="center">
    <div id="main_wrapper">
        <div id="main"></div>
    </div>
    <div id="sidebar"></div>
</div>
<div id="footer"></div>

2.左右结构，左边固定，右边100%

css代码:

<style>
#header{height:80px; background:#CCC;}
#center{overflow:hidden; zoom:1;}
#sidebar{float:left; width:200px; margin-top:10px; height:200px; background:#AAA;}
#main_wrapper{float:right; width:100%; margin-top:10px; margin-left:-210px;}
#main{height:200px; margin-left:210px; background:#999;}
#footer{height:50px; margin-top:10px; background:#CCC;}
</style>

HTML代码:

<div id="header"></div>
<div id="center">
    <div id="sidebar"></div>
    <div id="main_wrapper">
        <div id="main"></div>
    </div>
</div>
<div id="footer"></div>

3.左中右结构，左边固定，右边固定，中间100%

css代码:

<style>
#header{height:80px; background:#CCC;}
#center{overflow:hidden; zoom:1;}
#sidebar-l {float:left; width:200px; margin-top:10px; height:200px; background:#AAA;}
#main-wrapper {margin-top:10px; float:left; width:100%; margin-left:-420px; height:200px;}
#main {margin-left:438px; background:#999; height:200px;}
#sidebar-r {float:right; width:200px; margin-top:10px; height:200px; background:#AAA;}
#footer{height:50px; margin-top:10px; background:#CCC;}
</style>

HTML代码:

<div id="header"></div>
<div id="center">
    <div id="sidebar-l">这里是左边</div>
    <div id="main-wrapper">
        <div id="main">这里是中间</div>
    </div>
    <div id="sidebar-r">这里是右边</div>
</div>
<div id="footer"></div>