Make all official styles responsive

[iangreenleaf]

In theory this should be pretty easy once we have the right pieces. We can pull in the base sheet from #139 and add it to modern.css that @baldwint put together in #92. Hopefully that will give all our older styles responsiveness.

That only leaves a couple new ones to be updated, namely Slate and Libre. Hopefully someone will volunteer to help me figure these out ;)