Cute little game!
Having to move the mouse around to look around edges and stuff with the candle felt really good. I think it could have benefited from being a bit longer; Not at the end - I felt that was hard enough, but maybe some simpler play at the beginning - some really obvious/easy stuff just so people could get used to the controls and idea.
My only critiques would be that not knowing where the mouse cursor was when the light was off or it was being geometry felt awkward. I feel like it's position should still have always been known, so I could have prepared more when using it sparingly. It was quite tricky in parts, but I think that was good. It could have benefited from some easier intro stuff at the beginning though so people could better understand the concepts before coming across the trickier platforming.
All in all though, a cute little game. Very neat!