Let's make a face with D3.js!
A yellow smiley face is drawn on an SVG canvas with D3.js, featuring eyes, eyebrows, and a mouth. The eyebrows transition up and down repeatedly over two-second intervals using D3's `transition()` and `attr()` methods. The face is built from basic SVG shapes—circles for the eyes and a path generated with `d3.arc()` for the mouth. All elements are positioned dynamically based on the SVG's width and height attributes.