Create simple dynamically centered frame css

I have a simple question for everyone. I am trying to work out how to generate a three column style css skeleton template. I want the middle frame to be centered, but not by statically saying left: 100px , etc.

It would look a little like this开发者_开发百科.

http://img847.imageshack.us/img847/566/centerframedynamic.jpg

How do I achieve this?

---

There are a whole bunch of three-column layouts with code to get you started here: http://www.maxdesign.com.au/articles/css-layouts/

---

You can use width with percentages. For example:

l.div{width: 25%; float:left; min-height: 150px;}
c.div{width: 50%; float:left; min-height: 150px;}
r.div{width: 25%; float:left; min-height: 150px;}