This example demonstrates fundamental DOM manipulation with D3.js by animating a smiley face whose eyebrows rise and fall. It shows how to build SVG shapes—circles for the eyes, rectangles for the eyebrows, and an arc for the mouth—using D3 selections and the `arc` generator. The eyebrows transition vertically over a four-second cycle via chained `transition().duration()` calls. The code uses D3 v5, selecting the SVG element and appending groups to position features around the center of the canvas.