As others said, increase the window size! There's no reason for it to be that small. The rules say you absolutely can do it: "You may scale the game's resolution up as long as the base resolution is still 84 x 48."

When you lose, I don't think it's necessary to go back to the main menu. It just makes restarting a bit more tedious.

I can see the appeal in the gameplay (although it is just copied from Super Hexagon), but in my opinion the player moves so fast that sometimes you overshoot and die anyway. The speed of the hexagons doesn't help, I felt sometimes like I just had to be lucky to get even the first one.

Super Hexagon! That works well under the Nokia 3310 restrictions, I think, and something like this could've been a "real" Nokia game. The difficulty is perhaps a little high, though, as I could rarely get past the first three hexagons. Maybe it could be slowed down a little.

Nice concept, wished the game resolution was higher but just more zoomed in on the pixels so the window wouldn't be small, and it feels like you need a miracle to happen to be able to progress in the game, even the first hexagon is almost impossible if not lucky... but maybe some other people enjoy that difficulty