HTML/CSS/Box Model/min height
min-height: 200px
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html>
<head>
<title></title>
<style type="text/css">
p {
padding: 10px;
margin: 10px;
border: 1px solid black;
background: lightgray;
position: absolute;
top: 0;
right: 0;
bottom: 0;
left: 0;
min-height: 200px;
}
</style>
</head>
<body>
<p>
This is a test. This is a test.
</p>
</body>
</html>