Interactive fixes

various fixes and tweaks for the interactive header:

![image](https://cloud.githubusercontent.com/assets/960919/3468708/5b8d62f2-02a2-11e4-8ecd-9342e3c91a59.png)

![image](https://cloud.githubusercontent.com/assets/960919/3468701/468ea85c-02a2-11e4-95c9-e2b222aed4d1.png)


Are we slowly killing the SVGs?