求大神幫忙看看哪里錯了，小弟新手盡力了。。
<style type="text/css">
body{ margin:0; padding:0; font-size:30px; color:#fff}
.top{height:100px;background:#ccc;}
.main{width:600px;height:500px;}
.left{width:200px;height:500px;background:blue;float:left;}
.right{height:500px;background:green;float:right;}
.foot{height:50px;background:orange;margin:0 auto;}
</style>
</head>
<body>
<div class="top">top</div>
<div class="main">
? ? <div class="right">right</div>
? ? <div class="left">left</div>
? ??
</div>
<div class="foot">foot</div>
</body>
</html>
2016-08-17
<!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">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>混合布局編程挑戰</title>
<style type="text/css">
body{ margin:0; padding:0; font-size:30px; color:#fff}
.top{ height:100px; background:#ccc;}
.main{width:100%; background:red; position:relative;}
.left{width:200px; background:blue;}
.right{background:green; position:absolute; top:0px; left:210px; right:0px;bottom:0px;}
.foot{ margin:0px auto; background:#f9c; clear:both;}
</style>
</head>
<body>
<div class="top">top</div>
<div class="main">
??? <div class="right">right</div>
??? <div class="left">left</div>
</div>
<div class="foot">foot</div>
</body>
</html>
這樣或許可以 ，右邊要自適應所以應該不能用float
2016-08-16
按照給的效果圖top、main、foot的寬度應該設置成一樣的。然后你.right沒有設置寬度所以他顯示的是默認的寬度。圖中main里面的left和right中間還有一塊紅色的區域，按照我的理解是，main的背景顏色是紅色的，然后left和right之間有個margin值。
<!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">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>混合布局編程挑戰</title>
<style type="text/css">
body{ margin:0; padding:0; font-size:30px; color:#fff}
.top{width:900px;height:100px;background:pink;margin:0 auto;}
.main{width:900px;height:600px;background:red;margin:0 auto;}
.left{float:left;height:600px;width:200px;background:blue;}
.right{float:left;height:600px;width:690px;margin:0 0 0 10px;background:green;}
.foot{height:150px;width:900px;margin:0 auto;background:orange;}
</style>
</head>
<body>
<div class="top">top</div>
<div class="main">
? ? <div class="left">left</div>
? ? <div class="right">right</div>
</div>
<div class="foot">foot</div>
</body>
</html>