Thank you so much for the feedback and kind words!
You're right—we didn’t have much time to add a proper tutorial, so here’s how things work:
During the night phase, you need to aim at enemies using your mouse (your flashlight follows the cursor), and then press X to “shoot” the light. When you hit an enemy, it gets knocked back. So you just need to "survive" the song.
Also we thought about web version, but again we submitted the game it at the last minute.