Really really good and very polished for a game jam, love the overall style and vibe of the game too, makes it a really chill vibe to play in. It also feels very satisfying when you solve the puzzle.
I think the learning curve might be a little too steep in this build, but I think this is mostly because of wanting to show off a variety of cubes in a smaller amount of levels perhaps, something that I don't think would be as much of a problem in a full game. I noticed one of the page comments mentioning trial and error maybe not being fun, I kinda disagree with this and I actually enjoyed the flow of maybe not fully understanding each of the cubes from the get go and instead just trying a few different placements of the cube to fully get it, the flow of the puzzle after pressing play is so short that I didn't mind doing it a multiple of times before I solved it.
A very strong base for a game here and would love to see where you could take it. Great job and congrats on the game!