Sure! Here's an example of a simple 3D parkour game implemented as a single HTML file. You can play it on a smartphone by tapping on the screen to jump from cube to cube and reach the green finish line.
This game uses a 3D-like effect by rendering cubes as rectangles. The player jumps from cube to cube to reach the green finish line. If the player collides with any cube, it's game over. Once the player reaches the finish line, a victory message is shown. Simply copy and paste the code into a single HTML file and open it in a web browser to play the game.