This example demonstrates a minimal setup for embedding D3.js visualizations within an HTML page. It renders a red SVG canvas using the `d3.select` and `style` methods, with the background color set directly on the SVG element. The page includes an empty SVG of 900 by 400 pixels and displays the text “Hello HTML” centered via CSS. The code uses D3 v5 and is structured for React, though the visualization itself relies solely on plain SVG manipulation without any data binding or complex rendering techniques.