How to make a background within a background?

[iDeamir]

This is a bit hard to explain, but basically what I am trying to do is make two backgrounds. One background will be for the actual forum and will remain white. The other background will be outside the boarders of the forum (to the left, right, top and bottom) and I will make that a different color.

I have done this before, I just don’t remember how, and I can’t look up the answer because it was on the phpbb support forum that is currently down.

Thanks in advance.

[will_hough]

Set one background in html or body and set another in a #wrap