This example demonstrates asynchronous data loading in a React application using D3 v6. It fetches a CSV file of CSS named colors from a GitHub gist via `d3.csv()` and displays either a loading message or a data summary through a React state hook. The code uses `useState` and `setData` to trigger re-rendering when the promise resolves, while a secondary helper parses the fetched text with `d3.csvParse()` to show file size in kilobytes.