Sure, here's an example of a generative art game implemented as a single HTML file with JavaScript, enclosed in script tags:
This game generates random circles with different colors on the canvas every second. The circles are drawn using the `arc` method of the canvas context, and the color and position of each circle are randomly generated using JavaScript.
You can save the above code into a .html file and open it in any web browser, including on a smartphone, to play the game. The canvas will continuously update with new generative art patterns.