A cute piece of work that's relatively simple, though I do feel the second puzzle should have been the first, as forcing the player to work with a single box helps elucidate the rules a little more cleanly which is what a first puzzle should work towards, whereas the actual first puzzle, while not hard, was a little annoying because it pushed just a little harder then a first puzzle typically requires for teaching a player the rules of the game.

That said, this is a fine, simple puzzle game and it was quite fun to play.