Good & fun puzzle game. Nice diversity in levels and a lot of levels and nicely gradually becoming more difficult.
Cute pixel graphics. Good use of light & dark. Did miss some audio background track and SFX. That would make the game even more fun to play.
ZERO UI good incorporated. Did need to read the instructions to know how to switch.
Overall a job well done and maybe update with some great audio in a future update to make it even better!