Fork of Let's make a face with D3.js!
A yellow smiley face with blinking eyebrows is rendered as an SVG using D3.js v5. The face is centered via a group transform, with circles for eyes, rectangles for brows, and a path built with the `arc` generator for the mouth. Two chained `transition` calls on the eyebrow group animate its vertical position, moving the brows up and down over two-second intervals. This demonstrates fundamental DOM manipulation and chained transitions in D3.