Sure! Here's a simplified version of a 2D side-scrolling platformer game implemented as a single HTML file using JavaScript. It includes three buttons for moving forward, moving backward, and jumping. The player character can jump on blue platforms but will pass through them if colliding from below. If colliding from the top or side, the platforms act as solid obstacles. Pictograms are not used, but you can customize the graphical assets as needed.
You can copy and paste this code into a new HTML file and open it in a web browser. Use the forward arrow key to move forward, the backward arrow key to move backward, and the upward arrow key to jump. Enjoy the game!