Awesome job! I love menus that are playable in some way so the level select was a cool addition. I also appreciate that even though the graphics were all really simple, there was color scheme and crispness of the edges that make it visually appealing :).
I liked the use of death as a puzzle mechanic in a fast paced game, and that you give time at the start if you don't move to plot out your course. I would've loved to see more puzzles like "Maze" which use the direction you die as a way of speeding up your time because that one was very satisfying to complete with the optimal time.
The only tweak I'd suggest is when the time runs out to give a bigger indication that you lost the level and also give a little pause before the player can start (maybe just like .25 second animation where you can't act so as not to slow down the game). I would get frustrated when I'd lose the level and immediately start moving so the timer would start ticking again and I'd feel rushed to complete and fail again. The reset button helps with this for sure, but I think it would be more satisfying with the short delay.