Its polished, the theme is right in front of you all the time, and puzzles are so well implemented. Difficulty also increments accordingly and tutorials teach you in a simple but effective way.
If I had to say something, could I ask for a hint of how many diamonds I have left to pick in the level selector? I also had some bugs in level 2-3 that didn't let me finish it with all the diamonds, the player got frozen picking the last one.
Despite of that, the game got me playing untill the last level. I wish you make an update after the jam so we can enjoy some more time puzzles.
Very nice game, congrats!