Nice game! At first I thought the music was weird, but after playing, it actually fits the game really well. The graphics are solid too.
As for my suggestions, I would try making it so you have a limited number of reveals, and each one you pop gives some kind of hint about where the coin is. That way it would be more challenging, since right now you can just spam-click to win.
Also, just a heads-up, at least on my computer the fullscreen button completely breaks the game. You might want to disable it.