This example displays a yellow smiley face that fills the browser window, drawn with SVG circles for the head and eyes and a D3 arc path for the mouth. It uses React to render the SVG elements, with D3 v5’s `arc` function defining the mouth’s semicircular shape. The face is centered and scales to the viewport’s width and height, with the head radius based on half the window height. React and D3 are combined to create the static visualization.