This zoomable sunburst visualizes the hierarchical flare dataset, showing nested categories as concentric arcs whose angular width encodes value. Clicking an arc zooms into that subtree with a smooth 750ms transition, while a central circle returns to the root. Built with D3 v5, it uses `d3.hierarchy`, `d3.partition`, and `d3.arc` to compute layout and geometry, with `transition.attrTween` animating arc paths and label rotations. The data loads from the `@observablehq/flare` module via the Observable runtime and renders as SVG with a rainbow color scale.