<!DOCTYPE html>
<html>
<head>
<style>
#container {
color: #fff;
height: 400px;
display: table-cell;
vertical-align: middle;
width: 600px;
background: #00d;
}
#content {
color: #fff;
width: 50%;
margin: auto;
background: #d00;
}
</style>
</head>
<body>
<div class="red" id="container">
<div class="blue" id="content">
this
<br/> is
<br/> a
<br/> block
<br/>
</div>
</div>
</body>
</html>