WordPress Bottom Bar image won't tile/repeat

Hi there everyone 🙂

Been pulling my hair out with this one… I’m currently running Chris Wallace’s “Gallery” Theme (v1.5.3), which is a Thematic child theme. I have the bottom of my page set up with a few widgets, and I’m pretty sure I’ve put them in the right place as the theme instructs, but on the site itself, the darker gray image won’t tile or repeat. I’m not really sure what the problem is, so it’s difficult to describe, but you can see what I mean at the site:

http://www.scottstedman.com/

At the bottom of the page, there are three boxes, “Highest Rated Posts”, “Recent Posts”, and “Recent Comments”. At the top of those boxes, there is a darker gray box around them, but it should continue all the way to the bottom of the page.

Anybody know how to fix this?