<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title></title>
<style type="text/css">
*{margin: 0;padding: 0;} //清除格式，不然会出现滚动条
.wall{
width: 100%;
height:100%;
position: absolute;
display: flex;
justify-content: center;
align-items: center;
background: #000000;
}
</style>
</head>
<body>
<div class="wall" >
<a href="#"><img src="img/404.jpg"/></a>
</div>
</body>
</html>
原文：http://www.cnblogs.com/run666/p/7196920.html