A donut chart displays the relative proportions of four numeric values, each rendered as a colored arc segment around a hollow center. The chart uses a gradient interpolated between two colors to distinguish the slices. Built with React and rendered as SVG, the visualization relies on d3.v6's pie generator and arc path constructor to compute the segment geometry, while d3.interpolateRgb assigns the fill colors. The data itself is a fixed array, not loaded from an external file.