Fork of Let's make a face with D3.js!
A smiley face rendered with SVG demonstrates fundamental DOM manipulation and animation in D3.js. The yellow circle, eyes, eyebrows, and arc-based mouth are constructed using selections and the `d3.arc` generator. The eyebrows move via chained `transition` calls over two-second durations, shifting their group's `transform` attribute up and down. The animation loops by alternating between two translate positions, while the static elements remain fixed. D3 v5 handles the SVG creation and all attribute updates.