This example builds a smiling face out of SVG shapes using D3.js v7, with a yellow circular head, two eyes, rectangular eyebrows, and an arc-based mouth. The code loads D3 from UNPKG and uses the `select` API to target the SVG element, then applies chained `transition` calls with a 2000-millisecond duration to animate the eyebrows up and down. The construction relies on D3's `arc` generator for the mouth path and explicit coordinate calculations for positioning features relative to the canvas center.