为什么改不了div right的背景颜色
<style type="text/css">
body{ margin:0; padding:0; font-size:30px; font-weight:bold}
div{ text-align:center; line-height:50px}
.main{ width:960px; height:600px; margin:0 auto}
.left{ width:300px; height:600px; background:#ccc; position:absolute; float:left;}}/*左浮动样式*/
.right{ width:660px; height:600px; background:red; position:absolute;float:left;}/*右浮动样式*/
</style>
</head>
<body>
<div class="main">
<div class="left">left</div>
<div class="right">right</div>
</div>
为什么改不了div class="right"的背景颜色