Issue title: Double scrollbars in player on Windows
 Issue body: See this screenshot:

![image](https://cloud.githubusercontent.com/assets/858967/19342516/15be7464-912a-11e6-91df-c4ef561de1af.png)

[(Source)](https://twitter.com/le_re/status/786486426703503360)
 Comments: 
 Comment 0: It would be great if someone could take a look at fixing the CSS for this on Windows! Might just be a matter of setting the overflow to hidden on the x axis?
 Comment 1: Dunno if this helps at all, but it's happening to me on MacOS (Yosemite) too.
 Comment 2: I'm seeing it on my Ubuntu box as well. I'll take a stab at fixing it.
 Comment 3: @joethephish does this need to be closed? It looks like the above PR was intended to close it, but didn't due to the insertion of the word "issue" in "fixes issue #66".
 Comment 4: Oops! My bad. I'm a GitHub newbie and didn't know about GitHub automatically closing issues if you [use the right words](https://help.github.com/articles/closing-issues-via-commit-messages/).

As far as I'm concerned, this is ready to be closed.
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