What a great game! My only complaints are the symbol colors sometimes blend into the door and it's hard to see the shapes, and one of the doors has trouble opening -- I think it's on the level where it's two green and two blue doors, and the answer is all the way on the right.
Regardless, I got knocked down a few times and I still came back to try again! I eventually made it to the top. These were some satisfying puzzles :). Great work!