关于左右自适应问题，好好看会发现很有意思

左面自适应，右面固定200px；

body{ margin:0; padding:0; font-size:30px; color:#fff}
.l{margin-left:-200px; height:500px; background:blue; position:absolute;width:100%;}
.left{ margin-left:200px; }
.right1{ width:200px;height:500px; background:#9C9; float:right;}




left
 right

左面固定右面自适应

body{ margin:0; padding:0; font-size:30px; color:#fff}
.top{height:100px; background:#ccc}
.left{ width:200px; height:500px; background:blue; float:left;}
.right{ margin-left:210px;height:500px; background:#9C9;position:absolute;width:100%;}
.foot{ height:50px; background:#F63;clear:both; }






top

    right
    left

foot