Initial chrome-based styles

Here's a stab at styles for windows 8 based on the browser Chrome. I talked with Yuan about changing the visuals somewhat, but I wanted to go ahead and see if you had any feedback or suggestions as well.
I'm using a trick with -moz-appearance: none and leaving the min-width and width values at 3px to give the splitter a larger hit area. 1px is pretty tiny when scrubbing a mouse over it.

see osx.css in the latest version.