Awesome work, the game is really polished and the pixel art is amazing.
I specially like the presentation, menu design and the color coding are well done.
The music is good and gives a solid wipe. I would personlly prefer a more action pact soundtrack for such a tipe of game but thats just me.
I did not notice any major bug.
Gameplay wise its a simple loop but well executed. The player instantly knows what to do.
One thing that is a little bit frustrating: the spikes (that appear on the side) are not telegraphed like the beams, so if you are on the edge and they spawn you die because of bad luck, not because you made a mistake.
If you want to further work on it you could add some new game mode. A boss mode where collecting does damag, the longer the snake the more damage the boss takes. The bosses could have different attack pattern like in Undertale.
But it is completly fine as it is, small well polished well executed game!
Keep up the good work ;)