Smiley Face Part I
This example renders a smiley face using React and D3’s `arc` generator, with SVG circles for the face and eyes. The mouth is drawn as an arc path, while the background circle and facial features are positioned via D3’s `centerX` and `centerY` coordinates within an SVG group. React manages the component structure, and D3 v7 computes the arc’s path data. The visualization uses static hardcoded values for dimensions and colors, with no data source or interaction.