Now this was a head scratcher. I didn't finish a few of the levels as I had no clue how to make them work. Challenging puzzle games like this on are my favorites as you feel so stupid when you finally solve it hahah. Great job with the game over all, I liked the simple style of it and will return to solve the rest :D
I don't know if you've heard of Game Development World Championship before (gdwc2019) but it's a competition for indie game developers where they can submit their games and it's free! It's great if you want some more visibility for the game and it only takes a couple of minutes to join :)