As an AI text-based model, I can provide you with an example of a simple game implemented as a single HTML file enclosed in script tags. Please note that this example has a basic structure and can be expanded upon to include more features and functionality.
This game implements a simple particle system, where particles (represented by white squares) fall from the top of the canvas. The player interacts by observing the falling particles. You can customize the appearance and behavior of the particles to suit your needs.