don't use unneccessary css !important tags

As far as I can tell, removing !important doesn't change the
behavior here.

Plus, given the limited time of the event, I can think of lots of
other things I'd prefer to talk about, rather than explain this
particularly contested css feature. ;)
Merge pull request #156 from michaelkirk/remove-unnecessary-css

don't use unneccessary css !important tags