1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
| <!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title></title>
<style type="text/css">
.root{
width: 600px;
height: 600px;
background-color: blue;
margin: 0 auto;
position: relative;
}
.one{
width: 300px;
height: 300px;
background-color: black;
position: absolute;
left: 0;
right: 0;
top: 0;
bottom: 0;
margin: auto;
}
</style>
</head>
<body>
<div class="root">
<div class="one"></div>
</div>
</body>
</html>
|
