This example renders a smiley face as a reusable set of React components, using SVG for all drawing. The face is composed of a yellow background circle, black-outlined by a `BackgroundCircle`, and two `Eyes` positioned with offset coordinates. The `Mouth` component uses the `d3.arc()` API to create a curved path, and the code places multiple mouth instances—including rotated and translated variations—to form a complex expression. All positions and sizes are computed from the SVG width and height, with no external data source.