div水平垂直居中方法一：
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title></title>
<style type="text/css">
#test{
position: absolute;
width: 100px;
height: 100px;
background: pink;
left: 0;
right: 0;
bottom: 0;
top: 0;
margin: auto;
}
</style>
</head>
<body>
<div id="test"></div>
</body>
</html>
<!DOCTYPE html>
<html>
<hea
