Very nice, but this is not a one-button game, as you have to move a pointer about. The game should be possible to start, play, and restart using a single button (e.g. SPACE BAR, or the left-click with no need to move the pointer).
Thank you so much for your suggestion. And from that, I have updated the game to only be controlled by one button that is the "Left-Mouse Button" and completely removed any pointer movement.