I must say, pretty much everything is impressive in this game. The concept is clever, the music is well used and pleasant, the art is nice… What I like the most is that it's full of polishing, like the tiles slightly tilted, the use of the light, or even the sounds effects.
The level 2 feels more difficult than the others, maybe because of an instrument playing between long intervals, making it easy to miss. But overall, it's a really great puzzle. Amazing job!