This example shows a stylized smiley face built with D3.js v5, rendered as SVG with animated eyebrows that move up and down repeatedly. It demonstrates fundamental DOM manipulation by selecting an SVG element and appending groups, circles, rectangles, and a path for the mouth. The code uses D3’s `select` and `arc` APIs, along with chained `transition().duration()` calls to animate the eyebrow positions. The face is centered with a magenta circle background, and the animation loops via transition chaining without external data, relying purely on hardcoded geometric constants.