This example renders a 6x3 grid of procedurally generated smiley faces using React and D3.js (v5). Each face is composed of modular React components—BackgroundCircle, Eyes, and Mouth—assembled within an SVG container. The mouth is drawn using D3’s `arc` API, while facial features, stroke widths, and radii vary randomly per face. The data source is a D3 `range` array driving the grid layout, with randomness applied for visual variety.