This example renders a yellow smiley face in React, sized to fill the browser window. It uses SVG shapes—a large circle for the head and two smaller circles for the eyes—positioned relative to the viewport’s center. The React component calculates dimensions from `window.innerWidth` and `window.innerHeight`, applying offsets for eyes and a stroke width for the face outline. ReactDOM mounts the SVG into the DOM, with the mouth omitted from the visible output.