This example displays a smiley face built with React and D3, using SVG circles for the face and eyes and a D3 arc path for the mouth. The face is centered on a 960 by 500 canvas, with gold fill and black accents. React 17 manages the component structure, while d3.arc computes the mouth’s curved geometry from inner and outer radii plus start and end angles. The code explicitly sets dimensions, offsets, and radii as constants, rendering all elements within a single transformed group.