This example shows loading a CSV dataset of CSS named colors and rendering each color as a horizontal bar, producing a stacked spectrum across the page. While the data is being fetched with d3.csv, the app displays a large "Loading..." message. Using React hooks (useState, useEffect, and useCallback), the component manages the asynchronous data state and updates the DOM once the CSV arrives. The bars are plain React divs with inline styles that set the background color from the CSV’s “RGB hex value” column, giving a simple visual summary of the full color list.