This example shows a yellow smiley face with eyes and eyebrows that animate in a continuous up-and-down motion. The face is drawn entirely with SVG shapes, including circles for the head and eyes, rectangles for the eyebrows, and a path built with the `d3.arc` generator for the mouth. D3.js v5 is used for DOM selection and manipulation, while chained `transition().duration()` calls alternately raise and lower the eyebrow group. The code imports `select` and `arc` directly from the `d3` module, and positions elements relative to the SVG’s computed width and height.