This example shows a stylized smiley face built with React and D3, featuring yellow circular head, two eyes, and a curved mouth. The face is centered within an SVG canvas, with the head drawn as a yellow circle with a black stroke. The mouth is generated using D3’s `arc` generator with specified inner/outer radii and start/end angles, producing a semicircular shape. React renders the SVG elements declaratively, while D3 v7 provides the arc path calculation for the mouth.