Sure, here's an example of a simple text-based game in a single HTML file using JavaScript:
This example demonstrates a text-based game where the player must solve math problems to escape a 7-story school with different enemies on each floor. One of the enemies is the Principal, who will send the player to detention if caught. The game is operated assuming smartphone operation and uses text-based prompts instead of pictograms.
Please note that this is a basic example and can be expanded upon with further game mechanics, graphics, and user interface enhancements.