This example renders a full-screen smiley face using React and SVG. It draws a yellow circle with a black stroke, positioned at the center of the viewport, and adds two smaller black circles as eyes. The dimensions and positions are computed from the browser window’s width and height, using React’s JSX syntax to define the SVG elements and a translate transform to center the figure. The code uses React 16.9 and ReactDOM to mount the component into the root DOM element.