Here's an example of a game implementation as a single HTML file using JavaScript, enclosed in script tags. The game is about being trapped in a McDonald's and trying to escape from a clown. The game mechanics are simple and can be played on a smartphone. Pictograms are used to enhance the visual experience.
Note that this implementation is a simplified example and does not include a full-fledged game with extensive graphics or complex gameplay. It aims to demonstrate the use of JavaScript and basic game mechanics within a single HTML file, suitable for smartphone operation.