This starter template demonstrates a blank React and D3 visualization scaffold with a gray SVG canvas and visible margin guides. The code uses React 16.13.1 for component rendering and D3 v6 for future data-binding utilities. A reusable `VizContainer` component abstracts the SVG group element and follows the margin convention, accepting props for dimensions and spacing. Running through the `ReactDOM.render` call, it loads libraries from CDN and displays only the container structure without any actual data or chart marks.