This example shows how React manages D3-loaded data to render a pie chart of CSS named colors. It loads a CSV of color names and hex values using `d3.csv` into React state via the `useState` and `useEffect` hooks. Each slice is drawn as an SVG `<path>` using `d3.arc` and `d3.pie`, with the fill color set directly from each row’s `RGB hex value`. While the data loads, a large “Loading…” message appears. The visualization renders entirely in SVG within a React component.