An extremely well-scoped concept executed flawlessly. The flow of the levels feels very smooth and intuitive. You did a great job introducing the mechanics gradually one at the time so that they are easy to understand. The game is a joy to play! The QoL features are very much appreciated, especially the reset button/key combo.
The graphics and sound are good examples of being simple, but still fitting the game really well.My only suggestion is that a bit of variety with the color palette from level to level could help make your game look more appealing in screenshots to visually convey the variety your game already has in its gameplay.
This is probably the shortest review I've written and it's because I don't really have anything more constructive to say ;)