A yellow SVG face with black-outlined features animates its eyebrows and mouth. D3.js v6 shapes the face using `arc()` for the smile and appended `circle` and `rect` elements for the eyes and brows. Chained `transition()` calls with a two-second duration repeatedly move the eyebrows upward and adjust the mouth’s inner and outer radii, creating a looping expression. The face is centered and scaled using the SVG’s dimensions in a React-based starter.