This example depicts a stylized smiling face constructed with SVG primitives. A large yellow circle forms the head, with two black circles for eyes and curved lines for eyebrows. The face is rendered using React and D3, with the mouth created using the `d3.arc` API to generate an arc path. The visualization uses radial gradients defined in SVG defs to add subtle shading to the face and eyes, rather than using an external data source.