<!DOCTYPE HTML>
<html>
<head>
<meta charset="utf">
<title>relative样式</title>
<style type=:"text/css">
#div1{
width:200px;
height:200px;
border:2px red solid;
position:relative;
left:100px;
top:50px;
}
</style>
</head>
<body>
<div id="div1"></div>
</body>
</html>还有left, right top bollom都要反着写吗？