Sure! Here's a simple platformer game implemented as a single HTML file using JavaScript and enclosed in script tags. The game is designed for smartphone operation and uses pictograms for visual representation.
In this simple platformer game, the player is represented by a red square, and they can jump by tapping and releasing the screen. The game loop continuously applies gravity to pull the player down, and the `requestAnimationFrame` function enables smooth animation.
Please note that this code only provides a basic structure for a platformer game and does not include any level design, enemy or obstacle interactions, or scoring. You can expand on this code as per your requirements to create a more comprehensive platformer game.