body border, how can I set it to 800px

[chiselneck]

I need to add a 2px #000000 border around my forum and set it to fit 800px in width and auto in height. I've added the following CSS to the Edit / Fonts Colors etc > All Style Options > "Body" Extra CSS Atributes:

margin: 10px;
background-image: url('http://mypage.com/images/bckart.jpg');
border: 2px solid #000000;

But I've had no luck getting the 2 px border to a 800px width.
Any suggestions?

Thanks

Okay so I figured out to CSS for this and got the border around my page as it needed to be... now I need to center my page within the browser window.

Heres the CSS code I've written so far to get the border around the page:

Edit / Fonts Colors etc > All Style Options > "Body" Extra CSS Atributes:

margin: 10px;
background-image: url('http://mypage.com/images/bckart.jpg');
width: 800px; height: auto; border: solid 2px #000000

Any suggestions on how to get the page centered in the browser window?
Thanks

Okay, I've just about got this figured out. I got the border to fit my page... perfect.
Then I worked on my CSS until I got the page to center back up... looking good.

align: center;
margin: 0 auto;
background-image: url('http://mypage.com/images/bckart.jpg');
width: 800px; height: auto; border: solid 2px #000000

This also fixed my repeating image issues in my or post. So the forum is looking great so far.
The one thing remaining is to set the margin to 10px from the top of the browser... but this kills my center CSS. So I decided to try and figure out how to create a <br> break in CSS.

Nothing has worked as of yet.
Any suggestions?
Thanks.