Sure! Here's an example of a playable game implemented as a single HTML file using JavaScript. The game features a cat player that moves around a city trying to find gold bars. When the player finds all five gold bars, a message saying "You win!" will be displayed on the screen. To simulate smartphone operation, the game uses arrow buttons for movement. I've used pictograms to represent the cat player and gold bars.
You can save the above code in a file with an HTML extension (e.g., `game.html`) and open it in a web browser to play the game. The game will start automatically, and you can move the cat player around the city by using the arrow buttons on your keyboard. When you find all five gold bars, the message "You win!" will be displayed on the screen. Enjoy the game!