Hello HTML
This example renders a smiling face using React and SVG, composed of a yellow background circle, two eyes, and a mouth. The drawing is built from separate React components, each returning SVG elements, and is assembled inside a single `<svg>` tag. The mouth shape is generated programmatically using the D3 `arc` function, which defines an annular sector with specified inner and outer radii and angle ranges. The face is centered using an SVG group transform, and all elements are positioned relative to the center point.