This example shows a simple smiley face rendered as an SVG graphic, with its position and size dynamically scaled to fill the browser window. The face is composed of basic shapes—a yellow circle for the head, two black circles for the eyes, and a mouth created using the `d3.arc` generator with specified inner and outer radii. The layout uses React components to structure the SVG elements, while `window.innerWidth` and `window.innerHeight` determine the canvas dimensions. The code relies on React 16.9 and d3 v7, with the mouth path generated by `arc().innerRadius().outerRadius().startAngle().endAngle()`.