This project is a Godot plugin that is available on GitHub.
The GitHub repository has this demo included.
This web demo is just a courtesy and more importantly, a test I use to prove that the plugin works. It was not designed for mobile prompts/touch. Maybe when I get some time I will make the web demo more mobile friendly.
You can check out the OpenVAT for Godot Introductory video: https://youtu.be/0Ok142yRlog to see the demos in action.
Feel free to use this Godot plugin in your web based mobile friendly games.