Fix the spacing in the global header on devices

Due to the way the extra spacing is added where the text used to be on
mobile it pushes the menu down to far. This removes that space.

![Header before and after](http://f.cl.ly/items/0r1X1P2p3s0Q1h2V2v15/Screen%20Shot%202013-08-29%20at%2015.03.01.png)