This example shows a yellow smiley face rendered with a black outline, two eyes, and an implied mouth, centered on the screen. The face’s size adapts to the browser window. Built with React and ReactDOM, it creates SVG circle elements using JSX, calculating dimensions from `window.innerWidth` and `window.innerHeight`. The code positions the face with an SVG `<g>` transform and uses stroke width and radii to define the facial features.