Sure! Here's an example of a simple matching box game implemented as a single HTML file, using JavaScript and pictograms:
In this game, you have a grid of boxes, and upon clicking a box, a pictogram is revealed. The objective is to match two boxes with the same pictogram by revealing them sequentially. If the two revealed boxes match, they will remain visible (marked as matched). If they don't match, they will be hidden again after a brief delay.
You can copy the above code into a single HTML file (e.g., `matching_box_game.html`), and open it in a web browser on your smartphone to play the game.