<!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=gb2312" />

<title>css定位布局_相对定位</title>

<style type="text/css">

#body,div{

margin:0;

padding:0;

}

#main{

width:500px;

height:500px;

border:1px solid black;

margin:0 auto;

}

#one,#two,#three{

width:100px;

height:100px;

background:red;

}

#two{

background:green;

position:relative;

top:100px;

left:100px;

}

#three{

background:blue;

position:relative;

top:-100px;

left:100px;

}

</style>

</head>

<body>

<div id="main">

<div id="one">1</div>

<div id="two">2</div>

<div id="three">3</div>

</div>

</body>

</html>