Sure! Here's an example of a game implemented as a single HTML file using JavaScript. The game is a simple side-scrolling jumping game where you control a square and need to jump over obstacles. You can change the color of the square using buttons. The game is designed for smartphone operation and includes pictograms.
To play the game, tap the screen to jump over obstacles. You can change the color of the square by tapping the buttons with different color choices.
To run the game, simply copy and paste the code into a new HTML file, save it with a `.html` extension, and open it in a web browser (preferably on a smartphone for the full experience). Then you can tap the screen to jump, and use the color buttons to change the color of the square. Enjoy the game!