[RD]How to get my banner to stretch to the bottom?

[collidingstars]

I'm really not sure how to explain this o.o but I'll provide examples.

I've seen forums where their banner is at the top, then kind of stretches itself to the bottom? I guess it's quite popular, so I'm not sure what I'm missing. It's very lovely, and I'd really like to have it.

Here is an example:
acaciapride.proboards.com/

I believe this is the same thing as well:
xuniverse.proboards.com/

Best example of what Im interested in:
breakingpointx.proboards.com/index.cgi

[Kami]

[codeindex] - border around forum. :]

[collidingstars]

Ahh exactly what I need! I didn't think of it being a border. Thanks!

[Kami]

Any time. :]