This example shows a classic smiley face composed of a yellow circle, two black eyes, and a curved mouth, centered within an 960×500 SVG viewport. Built with React and D3 v5, it uses a `<g>` transform to position the face elements, static circle coordinates for the head and eyes, and a D3 `arc()` generator to create the mouth path. All geometry is hardcoded as constants, and the rendering occurs purely through SVG markup, with the app mounted to the DOM via `ReactDOM.render`.