This example demonstrates a minimal D3.js setup within VizHub, displaying the text "Hello VizHub!" centered on the page. It shows how to import D3’s `select` function from the bundled library and a local ES6 module exporting a message string. The code uses `d3.select` to set the text content of a `div` element with the ID `message`. Styling comes from an external CSS file, and the page loads D3 v5 from a CDN via UNPKG.