This is a great puzzle game! The mechanics are well intruduced, the ramp of rising difficulty is just right - never got stuck at any point.
What else can I say? Well, the missing music is a bummer for sure. Having no SoundFX audio feedback and no background music has a huge impact on the game experience. Lucky for you, this is pretty easy to improve - there are so many talented Jam composers out there.
I always feel a little jealous of minds like you being able to create such great puzzle games . Take this confession as a compliment - it is really meant as such. I wish our ways somehow would have crossed before. The graphics are okay, but the potential of your game deserves maybe a little more unique aesthetics.
Well enough said, I wish you and your project all the best! Good job so far!