Sure! Here's an example of a simple game implemented as a single HTML file with JavaScript, enclosed in script tags:
This game displays random pictograms in the center of the canvas, and the player needs to click on the displayed pictogram within a certain time limit. If the clicked pictogram matches the displayed one, the score increases by 1. Otherwise, the game ends. The player can continue playing until they make a mistake. The current score is displayed on the page.
To play the game, open the HTML file in a web browser, preferably on a smartphone or a device with touch support. Click on the displayed pictogram within the given time frame to increase your score. Enjoy!