Great game and great idea. Though it took me a second to figure out how to destroy the on coming blocks, once i did it felt very engaging.
one issue though as bad rng and how fast the gun moved, making it extremely difficult to hit the blocks with the correct colour, often leading to me needing to spam at the edges to cycle through the colours, which did lead to some accidental shots.
Id say just slow down the gun a little bit and maybe add a more official spot to shoot at to remove colours you dont need.