I am having a browser compatibility issue that I can't figure out. Because we use php, our

site is located on our "shop" subdomain (http://shop.kalologie.com), and the rest of our site is hosted somewhere else. When we copy the header code into the "Top of Page HTML Editor" the pages on the shop subdomain look perfect in Internet Explorer. When we view the same subdomain pages in Firefox, however, the header appears higher and shifts to the right.
Any help would be greatly appreciated. Thanks...