Shapes and Colors with SVG and CSS
This example demonstrates a blank SVG canvas with a solid red background, produced by applying CSS styling directly to the SVG element. The page uses a D3.js selection via the `select` function to target the SVG and set its background color, while a separate stylesheet defines custom classes for lines and paths with stroke properties. Rendering is purely SVG-based, with D3 v5 loaded from a CDN to manipulate the document structure.