Can I change the footer color in FIVE template?

Hi All,

I'm working on the following site... in the FIVE template.

trikafit.squarespace.com

I would like to change the color of the footer--which begins just below the dividing line, and lists About Trika, Tools & Resources, etc --to black. I'm not a developer, but I'm fairly good at following directions. I've tried the simple css snippet below, but no luck:

#footer { background: #000; }

Does anyone have any suggestions? Any help would be greatly appreciated!

All the best,

Evan