This example displays the text “Hello D3 version 7” prominently on a blank page, with the body styled at a very large font size. It demonstrates a minimal D3 setup, selecting the `body` element and setting its text content via the `d3.select` API. The page loads D3 v7 from unpkg and executes the logic in `index.js` through a bundled script. No external data is used; the visualization is purely a static text rendering.