Great puzzle design! I love the mechanic of switching between planes and the boxes do a lot to increase the complexity despite being so simple to understand. I did get juked by the menu button since I thought it was a pause or would take me to a level select, so I had play through 1-11 all over again, but since I knew the solutions it wasn't too bad. My one complaint about the mechanics is being unable to see if a tile is light or not when theres a box on it.
I love puzzle games and this was definitely a hit! If you do end up making it so you can hold an arrow key to keep moving, like I saw you say in another comment, please make sure theres a delay between moving once and just walking if there's more stuff like this where your position matters, but I think you already know that.
Overall very polished game with cool puzzles and mechanics!