The art is an easy 5/5 for me, really lovely style that stands out immediately and is cohesive throughout. The color choice is excellent and the lighting looks great. The procedural animation was cool and silly and I had fun making the player "dance" around while standing by the radio. Can't say enough good things about the overall aesthetic.
The gameplay loop is a solid one: defend the house, get currency, buy ammo and upgrade your guns. It's a good base for a game and toggling the radio to start and stop the waves of zombies is a neat twist. Shooting the gun feels satisfying, and there's some nice visual and auditory juice that helps out. Unfortunately, I think the currency system needs a bit more balancing. I found myself in a seemingly endless loop of shooting zombies just to buy more ammo and never being able to afford any upgrades. After 4-5 times of killing as many zombies as I could, and then having to spend basically all my money/scrap on buying new ammo I got discouraged from continuing to play as it didn't seem possible for me to make any further progression. Maybe it was an issue with my playstyle but it took away from the overall experience.
I think you have beautiful visuals with a fun core game loop that just needs a bit more polishing and balancing of the currency/upgrade systems to bring the game to that next level. Really cool game, keep up the good work!!