This example shows a simple face rendered as an SVG using React, with a yellow circle for the head and two smaller circles for eyes centered on a 960×500 canvas. It combines React 17 and D3 v7, loaded via UMD builds from unpkg, with ReactDOM rendering the SVG elements directly. The code demonstrates basic JSX syntax, including curly braces to embed JavaScript expressions like `centerX` and `eyeOffsetY` for positioning. The stylesheet removes the body margin and hides overflow, allowing the visualization to fill the viewport cleanly.