Data Viz - D3 smilie
A yellow smiley face rendered in SVG sits at the center of a 960-by-500 canvas. Two solid black circles form the eyes, while a thick black stroke outlines the face against a dark background. The visualization uses static SVG markup with `<circle>` elements and inline styling, not D3.js functions or data bindings. It demonstrates basic shape composition and stroke styling in a minimal HTML page.