This example shows a blue smiley face with animated eyebrows that shift upward and return to their original position over a repeating two-second cycle. The face is built entirely with D3.js v5 SVG elements, including circles for the face and eyes, rectangles for the eyebrows, and an arc for the mouth. The eyebrow motion is driven by chained `transition` calls on the eyebrow group, using `duration` and `attr` transformations. The code also demonstrates basic selection and attribute manipulation in D3.