Hey, nice job! I appreciate the fact that you only were able to work on this game on Sunday, but I think this game provides a polished experience nonetheless.
Design [3/5]: There are two things I love about this game. The first is that every puzzle has multiple solutions, allowing players to choose their own path. The second is that the game doesn't bombard players with a patronizing tutorial. The developers knew that players were smart enough to figure out how the game works without hand-holding or even any text tutorials. After poking around for a bit, it becomes clear what the objective is and what you need to do to avoid trapping yourself into an unsolvable situation. I love that the goal of the game and how to achieve it isn't immediately obvious, but something that you have to discover through the gameplay itself.
Having said all of that, I don't think there's too much to the experience after that. A dominant strategy quickly emerged for me, and it wasn't long before I was just blowing through levels. I don't think there's enough depth to the gameplay to keep me engaged for longer than a couple of minutes. I think that what is there is executed brilliantly, but I think the gameplay gets repetitive very quickly, and I don't see how it could be expanded upon to add variety without destroying the simplicity (which, I believe, is one of the selling points for this game).
To sum up: I enjoyed playing it, but only for a couple minutes, and I don't feel very motivated to go back for more.
Adherence to the Theme [5/5]: The object of the game is to remove all the puzzle pieces until only one remains. Nice job!
Originality [4/5]: There's a card game called Set which is pretty similar to this game. Players have to form sets of three cards based off of color, shape, or number until the deck is exhausted. It's an interesting puzzle game, and it's functionally very similar to your game. Having said that, I think your game is still original due to the artwork and the ultra-simplistic design. After all, Set has an instruction manual that teaches players how to play the game, but yours doesn't require any such handholding. It's really nice!
Great job! Hope to see more from you in the future.