Forum Border (the quick and simple way)

I had several people asking for this for vB3 and here it is. It is very simple. Hope you enjoy it!

[DarknessDivine]

Thanks, this actually solved a BIG problem I was having...

[Lexina]

Awesome Hack mate! Works like a charm! Thanks so much for creating it

[edit] Also, if you add the CSS Attribute to the Body Background instead of the Page Background, it adds the border around the header image too.. looks heaps better for my forums because I have tables at the top and bottom of my header banner

[-Shocker-]

How do I bring in the border so it's close to my forums because I changed the width of my forum to skinnyer, so I want the page background to be farther in.