Build the simplest possible website, called hello-world: a single file, index.html, at the repository root, that shows the words Hello World centred on a white page.

Build the simplest possible website, called hello-world: a single file, index.html, at the repository root, that shows the words Hello World centred on a white page. Plain HTML with a few lines of CSS in a style tag. No JavaScript, no build step, no package manager, no external resources, no other files except a two-line README.md saying how to open index.html in a browser.

Nothing else.