用position属性实现绝对定位
<html>
<head>
<title>position属性</title>
<style type="text/css">
<!--
body{
margin:10px;
font-family:Arial;
font-size:13px;
}
#father{
background-color:#a0c8ff;
border:1px dashed #000000;
width:100%;
height:100%;
}
#block{
background-color:#fff0ac;
border:1px dashed #000000;
padding:10px;
position:absolute; /* absolute绝对定位 */
left:20px; /* 块的左边框离页面左边界20px */
top:40px; /* 块的上边框离页面上边界40px */
}
-->
</style>
</head>
<body>
<div id="father">
<div id="block">absolute</div>
</div>
</body>
</html>