Sure! Here's an example of a simple game called "Jasper the Dead Ghost Kid" implemented as a single HTML file using JavaScript:
In this game, the player controls a ghost kid named Jasper using touch interactions on a smartphone. The game canvas is a 400x400 square where Jasper can move around. For now, the game logic and touch interactions are not implemented, but this should give you a starting point to build upon and create a fully functional game.