Fork of Smiley Face Part IV
This example shows a classic smiley face rendered as a vector graphic using React and D3. The face consists of a yellow circle with a black outline, two black eyes, and an arc-shaped mouth, all positioned within an SVG canvas. The code defines the mouth using D3's `arc` API to specify its inner and outer radii and angular range. D3 version 5 and React are used to construct the SVG elements, with the entire graphic rotated slightly via an SVG transform.