HTML Starter
This example renders a yellow smiley face on an SVG canvas using D3 v5 within a React framework. It draws the head, eyes, and mouth as circle and path elements, with the left eye animating through a two-stage `transition` that changes its radius and vertical position. The mouth is created using the `d3.arc` generator with fixed inner and outer radii. The code demonstrates basic SVG attribute manipulation and chained transitions.