Sure! Here's a simple implementation of a billiards game in a single HTML file using JavaScript:
Billiards Game
In this implementation, there are two balls on the billiards board represented by two div elements with the CSS class "ball". The white ball can be moved by touching and dragging it on a smartphone screen. The positions of the balls are stored in variables, and the updateBallPosition function is used to update the CSS properties of the balls' positions.
Note: This is a basic implementation and does not include any ball collision or game rules. It's a starting point that you can build upon to develop a full-fledged billiards game.