CSS Centering
Fixed Width Divs
This is one of the easiest ways I know of to center a fixed-width div that works in IE, Mozilla and Opera (and probably most other major browsers) and it's a pretty simple concept.
First of all just a regular fixed-width centered div, something that might be a stand-alone box rather than a container for other content.
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
"http://www.w3.org/TR/XHTML1/DTD/XHTML1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" lang="en" xml:lang="en">
<head>
<title>CSS Centering - Example 1</title>
<meta http-equiv="content-type" content="text/html; charset=iso-8859-1" />
<style type="text/css">
body {
margin:0;
padding:0;
background:#000 }
#center {
top:50%; /*top offset*/
left:50%; /*left offset*/
width:600px;
height:400px;
background:#fff;
position: absolute;
/* this needs to be 50% of your total width, in this case 600px */
margin-left: -300px;
/* and the same for the height */
margin-top: -200px }
</style>
</head>
<body>
<div id="center"></div>
</body>
</html>
Which would turn out like this
Secondly a 100% high example, expanding on the same method. This would be ideal as a container for all other content as the height of other elements can then be set within it, just using height:100% in a content div can cause overflow problems if you have columns of different lengths:
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
"http://www.w3.org/TR/XHTML1/DTD/XHTML1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" lang="en" xml:lang="en">
<head>
<title>CSS Centering - Example 2</title>
<meta http-equiv="content-type" content="text/html; charset=iso-8859-1" />
<style type="text/css">
body {
margin:0;
padding:0;
/* this sets a guide for all elements used within the container */
height:100%;
background:#000 }
html>body #outer{ height:auto } /*needed for mozilla*/
#outer {
left:50%; /*left offset*/
width:760px;
height:100%;
/* stops overflow when one column is longer
than the other for elements inside this */
min-height:100%;
background:#fff;
position: absolute;
/* again 50% of your total width, in this case 760px */
margin-left: -380px }
</style>
</head>
<body>
<div id="outer"></div>
</body>
</html>
Which would turn out like this
And we're done.


