A React and D3 donut chart visualizes budget allocations across five categories, with a legend mapping category names to a color scale interpolated between coral and crimson. The `pie` and `arc` generators compute slice geometry, while `scaleOrdinal` assigns colors from the interpolated range. Percentages appear on slices via `arc.centroid`, and the `ColorLegend` component renders interactive-free color swatches with tick spacing. The chart uses SVG rendering with `d3.interpolateRgb` for gradient transitions and `format` for numeric labels, based on static data in the `donThemes` array.