As an AI text-based model, I can provide you with a basic outline of how you can implement a simplified version of the Super Mario Bros. game using HTML and JavaScript. Please note that a full game implementation like Mario Bros 1 would require a significant amount of code, resources, and graphical assets, which is beyond the scope of this simple example.
Here's an example of how you can get started:
Super Mario Bros
To run the game, copy the above code into a blank HTML file and open it with your web browser. You'll be able to control the player using the arrow keys on your keyboard. However, please note that this is just a basic starting point and does not include the full functionality and features of the original Super Mario Bros. game.