Sure, I can help you create a simple game using JavaScript inside a single HTML file. Here's an example implementation of a game called "Pictogram Match" where you need to match pairs of pictograms:
This code creates a simple game where you will see 12 cards (represented by pictograms) on the screen. When you click on a card, it will flip over and reveal the pictogram. The goal is to match all the pairs of cards. Once you successfully match all the cards, an alert will appear congratulating you.
Note: This is a basic implementation, and you can modify and enhance the game as per your requirements.