Sure! Here's an example of an idle game implemented as a single HTML file using JavaScript:
This single HTML file contains the code for an idle game. The game consists of a score display, a clickable element (`#clicker`), and an upgrade button. When the user clicks on the `#clicker`, their score increases by the current click power. The user can use their score to purchase upgrades by clicking the `#upgrade-button`. Each upgrade increases the click power and doubles the cost of the next upgrade.
Feel free to customize and expand upon this code to create a more complex idle game with pictograms or additional features!