Sure! Here is an example of a simple Tetris game implemented as a single HTML file using JavaScript and enclosed in script tags.
This implementation creates a simple Tetris game where the player can control the falling shapes using the arrow keys on their smartphone. The game is displayed on a game board with pictogram-like div elements. The game starts automatically and continues until the player reaches the top of the game board, at which point a game over message is displayed. The game also checks for and clears lines when a full row is formed.