I've been working with reveal.js a bit and you can change the background of individual slides with something referred to as the global state as seen here in the demo.
Are there other colors besides the ones mention (-soothe, -blackout and -alert) on this slide that can be applied (hit down key in the presentation to see the colors)? If so what colors?
You can do this to e.g. have a different background color for the final slide:
Declare a style for the background (given the class "the-end"):
Then have the final slide look like this:
EDIT (added by tyler rinker) You are correct but I wanted to be more explicit for future searchers. I added the following two segments.
Added this to reveal.min.css
Added this to reveal.css