A minimal D3 example demonstrates a simple color transition on a black square. The visualization shows a single `div` element changing its background color from black to red over ten seconds. The code uses D3 v4’s selection and transition API, calling `d3.select` and `.transition().duration().style()` to animate the style property. The page also includes a video tutorial link and a separate `index.js` file that imports `select` from D3 v7 to write text into the body, though this script is not referenced in the HTML.