Sure! Here's an example of a simple shooting game implemented as a single HTML file using JavaScript. Please note that this is a basic implementation and can be further enhanced with additional features.
To play the game, open the HTML file in a web browser (preferably on a smartphone) and use the left and right arrow keys to move the player and the space bar to shoot bullets. The objective is to shoot down the green enemies to earn points. The score is displayed at the top left corner. Have fun playing!