Mobile friendly fix

Hi, great website!
I made this quick fix to the article's style, so that the page stays inside the window and can be easily read on a mobile device.

Hope it helps!

p.s. I only modified the sass, the css needs to be generated from it 

Here is how it changes (from left to right):
![Screen Shot 2013-04-07 at 10 22 43 PM](https://f.cloud.github.com/assets/1282730/349388/17b20db6-9fc1-11e2-8ff6-b2434779a82b.png)