垂直居中的几种实现方法
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<!doctype html>
<html>
<head>
<meta charset="utf-8">
<title></title>
</head>
<body>
<style>
.wrap {
width: 300px;
height: 300px;
border: 3px solid #ddd;
display: table;
*position: relative;
}
.hack {
display: table-cell;
vertical-align: middle;
*position: absolute;
*top: 50%;
}
.cnt {
*position: relative;
*top: -50%;
}
</style>
<div class="wrap">
<div class="hack">
<div class="cnt">content</div>
</div>
</div>
<div class="wrap">
<div class="hack">
<div class="cnt">
<img src="http://pic002.cnblogs.com/images/2012/382256/2012080118323766.gif" width="50%">
</div>
</div>
</div>
</body>
</html>
纯CSS实现未知尺寸图片垂直居中
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