Earlier quoted context omitted.
What I would wish that I could do is just make it so that there was a link to the HTML file in the Readme. Click it and there you go. My impression is that this is discouraged. (Am I wrong about that?)
You can do that with Github Pages, but I'm not too knowledgable. But I copied your code in an codesandbox: https://ijlkq.csb.app/ Fork it if you want, I will delete it then (or on your request)
Apparently the contents of the page were somehow mangled a bit. As a result it is not functional.