A yellow circle face with eyes, eyebrows, and a mouth rendered in SVG animates as the eyebrows move upward and then back down. Built with d3.js v5, the example uses `select` and `arc` to construct the facial features, while `transition().duration()` drives the eyebrow motion. The SVG canvas is 960 by 500 pixels, with elements positioned via transform attributes and styled through a linked CSS file.