A D3.js example builds a yellow smiley face with animated eyebrows using fundamental DOM manipulation. The face is drawn with SVG circles for the eyes and a path created via the `d3.arc()` generator for the mouth. Eyebrow rectangles transition vertically upward and back down over two 2-second intervals using chained `transition()` calls. The code selects the SVG element, applies transforms to center the face, and uses static data attributes like `eyeSpacing` and `eyeRadius` to position features, rendering entirely in the browser with d3.v5.