<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title></title>
<style type="text/css">
html,
body {
height: 100%;
}
.div {
position: absolute;
/*height: 200px;*/
width: 800px;
background: yellow;
margin: 0 auto;
top: 0;
left: 0;
bottom: 0;
right: 0;
/*margin-top: -100px;*/
}
</style>
</head>
<body>
<div class="div"></div>
</body>
</html>
