This example shows a smiley face drawn with SVG circles, rectangles, and an arc for the mouth. Its eyebrows bounce up and down repeatedly in an animated loop. The code demonstrates fundamental DOM manipulation with D3.js v5, using `select`, `append`, and chained `transition().duration()` calls to animate the eyebrow group’s transform. The face uses hardcoded dimensions, no external data, and renders entirely through SVG primitives within a 960x500 canvas.