This example renders a smiley face using React functional components and ReactDOM to mount the app. It integrates React 17 with the UMD build, loading both React and ReactDOM from a CDN. The visualization is drawn entirely through React’s JSX syntax within an empty App component, which currently renders no visible output. The code sets up a minimal HTML page with CSS to hide body margins and overflow, but no SVG, canvas, or charting library is used.