How can I get my logo in the center of the header area of a browser page?

[Fenriz]

Hi!

http://test.armkb.com/
htaccess:
test
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As you can see, I have a specific problem. My vbulletin site has fixed width via doc_width variable (750px) and I made it centered via doc_margin variable. Ok, now I need to place a very long logo to be centered in a browser page.. beginning not from the left corner of vbulletin header, but from the top left corner of a browser page. Could anybody tell me plz how to do that?