Make columns fluid?

[bronteyork]

I've been trying to edit my template to make my columns (right, left and mid section) fluid, so the white background goes down all the way to the bottom. I have failed. :( I have an asp.net application and it is on a windows based server.

I have attached my original template. I was told that I need to make changes to the css part of the template.

I would be eternally thankful if someone could help me to make this work!

Thanks so much.
Viki