Sure! Here's an example of a simple platformer game implemented as a single HTML file using JavaScript and enclosed in script tags:
In this example, the player is represented by a red square that can be moved horizontally using the arrow keys. Additionally, the player can perform a jump by pressing the up arrow key. The game loop continuously updates the player's position and performs the jump animation.
Please note that this is a very basic implementation of a platformer game and may not fully meet all the requirements of a complete and functional game. It serves as a starting point that can be expanded upon to add more features, levels, and obstacles.