Render picks nicely on wide views of the home page.

The most interesting bit is definitely the system for monitoring if elements
are overflowing or not and calling back. I can walk through how it works
because it's a little obtuse, but the reason is that we want to avoid DOM
thrashing (reading DOM props triggers a reflow, writing can be buffered) so
we batch our reads and then loop through to see if anything changed and
call those things back. It's a little like the angular digest cycle in that way.