Footer background has a gap

While customizing my local.css, I realized that the background image for the footer region floats bottom, which I want it to do, but that leaves about a five-pixel gap between the content region and the footer itself, letting the page background show through between them. Filling in the background color with a hex value closes the gap, but that defeats the whole purpose of having a partially-transparent background image with rounded corners.

My question is, is there any way to shorten the height of the footer, or to possibly fill in the background above the background image without destroying the rounded corners? Any help would be appreciated.