Lets make a face
This example builds a cartoon face from basic SVG shapes—a yellow circle for the head, two black eyes, rectangular eyebrows, and an arc-based mouth. The code uses D3 v5 selections and the `arc()` generator to construct the mouth, while `transition().duration()` animates the eyebrows upward and back down over four seconds. All elements are grouped and centered using SVG transforms, with fixed pixel values controlling feature placement.