Can I make a fixed background image move with the page as I adjust the browser?

When the browser adjusts left and right, the fixed background image toward the middle of the page stays fixed. Is there a way I can keep it fixed so I can scroll up and down over it, but let it adjust left and right to stay aligned when the browser moves left and right (or when the browser windows width adjusts)?

http://epsilon144.com/?req=misc&page=i3