Share popover behind youtube video

When it's active, the popover correctly displays in front of the youtube video. However, when inactive, it displays behind the youtube video.

![screen shot 2014-01-21 at 00 13 04](https://f.cloud.github.com/assets/109850/1959507/d0e4176e-8230-11e3-84fc-a82eae3b8344.png)