This example shows a minimal HTML page with a red SVG canvas, demonstrating the simplest possible setup for a D3.js visualization. The page includes a static "Hello HTML" text and an empty SVG element, which is styled with a red background using `d3.select` and `svg.style`. It loads D3 v5 from a CDN and contains a `main.js` file that selects the SVG and applies the background color. This serves as a bare starter template for building more complex visualizations, with no data or interactive behavior implemented.