Smiley Face Part I
A grid of eighteen randomized smiley faces appears, each rendered as a yellow circle with black eyes and a half-circle mouth. The faces are generated in React using reusable components like `FaceContainer`, `BackgroundCircle`, `Eyes`, and `Mouth`, with the mouth created via `d3.arc`. Random properties for stroke width, eye placement, and mouth size are assigned per face using `Math.random()` and `d3.range`, and the SVG output is produced through React’s declarative element structure.