A smiling face, rendered entirely with SVG shapes, animates as its rectangular eyebrows repeatedly lower and raise over a two-second cycle. Built with D3.js v5, the visualization demonstrates fundamental DOM manipulation by using `select` and `append` to construct the face from circles, rectangles, and an `arc`-generated path for the mouth. Eyebrow motion is driven by chained `transition().duration(2000)` calls that tween the rectangles' `transform` attributes, shifting them vertically within the SVG canvas.