The aesthetics are quite nice - I appreciate low-poly style even if it's not my preferred style, and you certainly had a nice low-poly style. The UI and menus are nice and fleshed out, which is always good for a game jam game. The gameplay is nice and simple and the level design is quite nice - both in terms of gameplay and visual appeal.
My main issue was that there seemed to be a bug where the moment you collide with a non-box object (such as a wall or spike) you would be unable to move the box. I wasn't able to play through much of the game because of that unfortunately.
Overall - good stuff man! Keep it up!