This example renders two overlapping SVG circles, a yellow outer ring with a black stroke and a smaller black inner circle, positioned at the same center. The page also renders a React component that displays the text "H1" inside a root div. The visualization uses React 16.7.0 for component rendering, D3 v7.1.1 for SVG manipulation, and hardcoded circle attributes defined in CSS classes. The SVG output is static, with no interactivity or data binding beyond the fixed dimensions and styles.