Make text larger, page wider

The current descriptions are computed at about 11px, which I find very
difficult to read. These are the minimal changes I could come up with to make
the page more legible. It also changes the content width to 960px from 600px.

![[screenshot](http://cl.ly/image/210J0m433121)](http://f.cl.ly/items/1q0D3h1n3r3K1i1M211m/Image%202014-11-17%20at%2012.11.22%20PM.png)

If this is a welcome change, I'd like to do some more work to make the page a
bit more cohesive and accessible, while also improving the semantics of the
HTML. But I didn't want to start on that if the changes will be rejected.

Thanks for the awesome site!