This example shows a yellow smiley face built entirely from SVG shapes using D3.js v5, with animated eyebrows that move up and down in a repeating two-step transition. The face is composed of a circle, two eye circles, and a mouth drawn as an arc path via the `d3.arc` helper, all centered within an SVG canvas. The code demonstrates fundamental DOM manipulation by appending groups and elements with `select`, `append`, and `attr`, while the eyebrow motion relies on chained `transition().duration().attr()` calls to repeatedly shift their vertical position. No external data source is used; the visualization is purely programmatic.