<!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>css外层DIV半透明内层div不透明-弹出层效果的实现【实例】</title>
<style type="text/css">
<!--
body,td,th {
font-size: 12px; padding:0; margin:0;
}
.tanchuang_wrap{ width:600px; height:400px;position:absolute;left: 0px;top: 0px;z-index:100; display:none;}
.lightbox{width:600px;z-index:101; height:400px;background-color:red;filter:alpha(Opacity=20);-moz-opacity:0.2;opacity: 0.2; position:absolute; top:0px; left:0px;}
.tanchuang_neirong{width:353px;height:153px;border:solid 1px #f7dd8c;background-color:#FFF;position:absolute;z-index:105;left: 123px;top: 123px;}
-->
</style>
<script language="javascript">
function closeDiv(divId){
document.getElementById(divId).style.display = 'none';
}
function displayDiv(divId){
document.getElementById(divId).style.display = 'block';
}
</script>
</head>
<body>
<div style="width:400px; height:400px; position:relative; text-align:center;">
<div class="tanchuang_wrap" id="aaaa">
<div class="lightbox"></div>
<div class="tanchuang_neirong">
<p><span onClick="closeDiv('aaaa')" style=" cursor:pointer;">关闭</span></p>
这里是弹窗内容</div>
</div>
<span onclick="displayDiv('aaaa')" style="cursor:pointer;">点击我</span>
<p>测试通过，兼容IE6.0、IE7.0、火狐3.6、遨游等各大浏览器</p>
</div>
</body>
</html>Demo