Some feedback:
I tried to use arrow keys in the menu but they didn't work and when I saw "tap to start" I assumed that you must control the snake with the mouse.
Then it took me a while to realize that the snake turns towards the pointer. Was thinking that it just always does a 90 degree turn on click...
Otherwise it is a nice twist on the snake game. Gets pretty hard with the red stuff, but thats cool.
So about the controls. I would make it possible to navigate the menus with keys and then the instruction could be "Tap OR use wasd/arrow keys to start"
Oh and exit on web games just freezes the whole thing :D
Anyways, nice job with the game!