Let's make a funny face with D3.js!
This example demonstrates fundamental DOM manipulation with D3.js by constructing a yellow smiley face from SVG shapes, then animating its eyebrows. The face is built using D3 selections to append a circle for the head, two circles for eyes, rectangles for eyebrows, and an arc-generated path for the mouth. The code uses `d3.select`, `d3.arc`, and D3’s `transition` API to move the eyebrow group vertically over two seconds, creating a funny winking-like motion. All elements are rendered as SVG inside a 960×500 viewport.