Better mobile layout

Simple fix to display the categories better on small screens.

New:
![screen shot 2014-07-12 at 4 20 01](https://cloud.githubusercontent.com/assets/300693/3560306/307e5356-0963-11e4-83c6-b4d84005006a.png)
Old:
![screen shot 2014-07-12 at 4 20 35](https://cloud.githubusercontent.com/assets/300693/3560308/443f57d2-0963-11e4-8fea-6d31f6852a6e.png)