Sure! Here's a simple shooter game implemented as a single HTML file using JavaScript and enclosed in script tags. This game is designed for smartphone operation and uses pictograms for a better gaming experience. The objective of the game is to shoot the moving targets without hitting any squares.
To play the game, you can copy the above code and save it as an `.html` file. Open the file with a web browser on your smartphone, and the game should start. Touch the screen to shoot bullets at the moving targets and avoid the squares. If you collide with a target or a square, it's game over!