Sure! Here's an example of a simple Gravity Ball game implemented as a single HTML file:
To play the game, you can simply copy the above code and save it as an HTML file (e.g., "gravity_ball.html"). Open the file in a web browser (preferably on a smartphone for touch interaction). The game will start automatically, and you can drag the ball using touch or mouse input. The ball will be affected by the gravity, and you can change the gravity direction by dragging the ball up or down. Have fun playing!