Sure! Here's an example of a simple platformer game using JavaScript and HTML:
This code sets up a simple platformer game where the player can move left and right using the left and right arrow keys, jump using the up arrow key or space bar, and can collide with and stand on the green platforms. The player is represented by a blue rectangle and the platforms are represented by green rectangles.
Please note that this is a basic example and can be expanded upon to add more features, levels, animations, etc. Feel free to modify and improve it as per your requirements.