A donut chart displays all CSS color names with their corresponding hex values as colored arcs. D3 loads the data from a CSV file, while React state tracks the dataset and manages the loading state. The `arc` and `pie` generators from D3 compute the geometry, with each arc filled using the color’s RGB hex value. The visualization renders as SVG inside a React component, showing the integration of D3 for data loading and chart math with React for UI state management.