This example shows a smiley face rendered as a responsive SVG, centered on the screen with yellow circular head, black outline, two eyes, and a mouth arc. The face is built using React components, with D3’s `arc()` generator creating the mouth path. D3 v7 supplies the arc shape, while React 16.9 handles the DOM updates and JSX structure. Window dimensions set the canvas size, and all positions are calculated relative to the center.