This was a fun and challenging experience! The puzzles were really well designed, and you taught the mechanics to the player in a great way. However, the difficulty curve felt a bit off. some later levels were actually easier than the earlier ones.
I also prefer games to be in full screen mode, as the current size felt a bit small. As for the controls, it would be more comfortable if everything could be done with the keyboard since switching colors with the mouse felt a bit awkward.
Overall, a very polished and well-made game. Great job