I must say, your game is quite enjoyable and visually verry appealing. However, I broke it. Whenever I go to the right edge and refrain from consuming any food, I notice that I could easily reach score 1500 by repetitively moving up and down until the food respawn on inconvenient location right before me. It seems that along that particular line, boxes aren't being generateed.
Furthermore, I didn’t understood purpose of expanding the snake's size within the game. It only increase the game's difficulty without offering any corresponding rewards in form of reaching higher score. I enjoy this game way more when I start to ignore score and instead trying to make snake as long as possible