1 <!DOCTYPE html>
2 <html>
3 <head>
4 <meta charset="utf-8" />
5 <title>CSS实现div居中</title>
6 <style>
7 /*外层div居中*/
8 #main {
9 position: absolute; /*极为重要*/
10 background-color: blue;
11 width:400px;
12 height:200px;
13 left:50%;
14 top:50%;
15 margin-left:-200px;
16 margin-top:-100px;
17 border:1px solid #00F;
18 }
19
20 #content {
21 position: absolute; /*极为重要*/
22 background-color: yellow;
23 width: 200px;
24 height: 100px;
25 left:50%;
26 top:50%;
27 margin-left:-100px;
28 margin-top:-50px;
29
30 /*div内部文字居中*/
31 text-align: center;
32 line-height:100px; /*行间距和div高度相同*/
33 }
34 </style>
35 <body>
36 <div id="main">
37 <div id="content">
38 Sun
39 </div>
40 </div>
41 </body>
42 </html>