Smiley Face Part II
Drawn with React and D3’s `arc` generator, this SVG visualization places a classic yellow smiley face at the center of the viewport, sized to the full window. The face comprises three circles—the head and two eyes—plus a mouth path created by an arc with inner and outer radii, starting at 90 degrees and ending at 270 degrees. The code explicitly sets stroke widths, eye offsets, and mouth dimensions as constants, while React renders the SVG elements declaratively via the `App` component.