Impressive for a first game jam. I appreciate you using low-poly style.
The models, i have nothing to say, but they are simple and cute.
The game is very simple and cozy, but all of the invisible walls make it much more confusing because you don't understand where the walls end and where they start. I was disappointed by the lack of sound effects and music, and the ending softlocks the player so you can't press try again. I too, recommend you to use other skyboxes, rather than Unity's default one.
Since the game is easy and 60 seconds, make more games. I am interested.