DIV+CSS布局IE8和IE6的浮动层间距不同（求助）

<!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>

<title>文库</title>

<link rel="stylesheet" href="css/style.css" type="text/css"></link>

<script type="text/javascript">

<!--



//-->

</script>

</head>

  

  <body>

  	<div class="top">

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  	</div>

    <div class="main">

    	<div class="search">

    		文档搜索

    	</div>

    	<div class="menu">分类导航</div>

    	

    	<div class="type">全部文档分类</div>



    	<div class="right">

    		<div class="right_x" style="height: 150px">公告</div>

    		<div class="right_x" style="height: 300px">阅读排行榜</div>

    		<div class="right_x" style="height: 300px">下载排行榜</div>

    	</div>

    	<div class="hot">热门推荐</div>

    	<div class="type_x">详细分类</div>

    	<div class="type_x">详细分类</div>

    </div>

    <div class="bottom">底部</div>

  </body>

</html>

body{

	

}

.top{

	margin-right: 10px;

	/*border: 1px solid blue;*/

	text-align: right;

	font-size: 15px;

}

.bottom{

	margin: auto;

	margin-top: 10px;

	width: 1000px;

	height: 100px;

	border: 1px solid red;

	text-align: center;

}

.main{

	margin: auto;

	margin-top: 10px;

	width: 1000px;

	text-align: center;

}

.search{

	width: 100%;

	height: 75px;

	border: 1px solid blue ;

}

.menu{

	margin-top: 10px;

	width: 100%;

	height: 35px;

	border: 1px solid green;

}

.type{

	margin-top: 10px;

	width: 100px;

	height: 350px;

	float: left;

	background: green;

}

.hot{

	margin-top: 10px;

	margin-left: 110px;

	width: 650px;

	height: 350px;

	background: green;

}

.right{

	float: right;

	width: 230px;

}

.right_x{

	margin-top: 10px;

	width: 100%;

	background: green;

}

.type_x{

	margin-top: 10px;

	width: 760px;

	height: 350px;

	background: green;

}