A gallery of randomly generated smiley faces fills the screen, each face composed of a yellow circle with black outlines, stylized eyes, and a mouth. The example combines React components with D3's `arc` function for the mouth shape and `range` utility to generate the array of faces. Built with React 16.9 and D3 v5, it uses SVG rendering to draw each face with randomized stroke widths, eye offsets, and mouth dimensions.