Fork of Let's make a face with D3.js!
This example shows a smiley face built with SVG, where the eyebrows animate up and down in a looping motion. The face is constructed by appending circles for the eyes, rectangles for the eyebrows, and a path for the mouth using D3’s `select` and `arc` APIs. The animation uses chained `transition().duration()` calls to repeatedly move the eyebrow group between two vertical positions. The code loads d3.v5 from unpkg and renders entirely through SVG elements.