I don't know if the game is bugged or the last item is just insanely hard to see, but I could not restore color to the world.
This art style is aggressively charming, and I find it delightful. The main issue is that the exact placement of different objects has led to a lot of tangents (instances where delineation between exact forms is ambiguous or confusing) and misleading assets "poking out" from behind other ones. In a simple, one-screen hidden objects game...composition is KEY.