Sure! Here's an example of a simple Crossy Road game implemented as a single HTML file:
In this implementation, you can control the player using the arrow keys on your smartphone. The player needs to avoid colliding with the red obstacle as it moves downwards. If a collision occurs, an alert with "Game Over!" is displayed.
Note: This is a basic example and can be expanded upon to enhance the gameplay experience with additional features, levels, graphics, and scoring systems.