Sure! Here's a simple example of a 19 chapter color pixel platformer game implemented as a single HTML file with JavaScript code:
This is a very basic implementation of the game where the player (represented by a red square) needs to reach the seed (represented by a green square) in each chapter (represented by platforms). The player can move horizontally using the arrow keys. Once the seed is collected, the player moves to the next chapter, up to a total of 19 chapters.
Keep in mind that this is just a starting point, and you can add more game mechanics, levels, and improve the graphics and gameplay further based on your requirements.