This example renders a simple yellow emoji-style face with eyes and a curved mouth using React and D3 within an SVG canvas. The face is centered in a 960×500 viewport, with the head drawn as a circle, black-eye dots positioned symmetrically, and a mouth generated using the `d3.arc()` path generator. The code imports React, ReactDOM, and D3 from CDNs, and uses JSX with inline style to remove body margins and fill the screen.