It automatically resets when you close the game. Actually, the initial idea for the game was to be a standalone executable that would only reset when closing the app. However, when I worked on porting the game to WebGL, I forgot the fact that the game saves its progress in a binary file rather than some PlayerPrefs keys. The game(s) also have save slots, which I've disabled for the demo. I might post an update real soon that will include save slots that you can erase at any time, let alone a devlog explaining the flaw.