My sidebar won't move to the side. What am I missing?

I'm in the early stages of designing my own theme, but for the last 3 days I've been stuck on what should be a very simple step... Getting my sidebar to float to the side. The sidebar just sits at the bottom mocking me! :wink:

I've temporally uploaded it to

You can download the zip and all the theme files at:

It's based off _s and I'm trying to use a responsive design. If anyone could lend a hand I would really appreciate it.