This example renders a yellow smiley face that fills the entire browser window. Using React and ReactDOM, the application defines SVG circles for the face, eyes, and an implied mouth, with dimensions calculated from the window’s inner width and height. The face is centered via a transform, and its radius is set relative to half the window height, ensuring the graphic scales to any viewport. The code references React 16.9.0 and draws the smiley using SVG’s circle elements.