A yellow smiley face is drawn as an SVG circle with two black eyes and a half-moon mouth, all centered on a 960×500 canvas. The face is built with React 16.13.1 and D3 v6, using `d3.arc` to generate the mouth path and JSX transforms for positioning. Eye and mouth radii, offsets, and stroke widths are constants, while the mouth arc is defined with angles from π/2 to 3π/2. The SVG is rendered via `ReactDOM.render` with a fixed viewport and hidden overflow.