Hello, I'm having no luck tracking down the source of a setting/adjustment to the appearance of my site's header.

My store is at www.soapbin.com and when viewed in IE, it looks how I would expect it to. There's a gradient that runs from the top to the bottom of the logo, across the entire page.

However, in FF, my header_bg.jpg is truncated at about half of the logo. I have adjusted the header.php to reflect the larger logo size that I'm using as opposed to the stock classic layout. The header_bg.jpg that I'm using was just photoshopped over the original file.

It seems as if a css change needs to be made elsewhere, but I can't see it in the stylesheets...

Any insight is appreciated. The store is 1.3.7

Thanks in advance!