This example demonstrates a blank visualization canvas built with React and D3 v6, using a reusable `VizContainer` component that applies the standard margin convention. The component renders an SVG with outer and inner rectangles to visualize the margins, which can be toggled by changing the `showMargins` prop. The code loads React, ReactDOM, and D3 from CDNs, and sets up width, height, and margin variables for future chart development. The actual visualization area remains empty, serving purely as a starter template for building custom React+D3 charts.