Fork of Let's Make a Face Part I
This example shows a simple smiley face built from reusable React components, rendered as an SVG that fills the browser window. The face consists of a yellow background circle, two black eyes, and a mouth created using the `d3.arc()` API from D3 v7. The React components (`FaceContainer`, `BackgroundCircle`, `Eyes`, `Mouth`) compose the visualization, with the face centered using SVG transforms. The code runs in a React 16.9 production environment and imports D3 directly for the arc path generation, demonstrating a minimal component-based approach to SVG drawing.