This example renders a full-screen smiley face using React and SVG. The face is composed of a yellow circle with a black stroke for the head, plus two smaller circles for the eyes, all positioned relative to the center of the window. The React component computes dimensions from `window.innerWidth` and `window.innerHeight`, uses JSX to create SVG elements, and applies a `transform` to center the drawing. The code includes a commented-out static SVG version, but the active implementation uses ReactDOM to mount the dynamic visualization.