Smile face Part I
A smiling face is drawn from elementary shapes: a yellow circle with a black outline serves as the head, two black circles form the eyes, and a curved band (created by computing an arc path) forms the mouth. The code uses React and ReactDOM to render SVG elements, while D3's `arc()` API generates the mouth’s path data. All shapes are positioned relative to the center using a translation transform, with dimensions derived from constants for width, height, and stroke width.