Fork of D3 v5 Zoomable Sunburst
This interactive sunburst chart visualizes hierarchical data from the `@observablehq/flare` dataset, showing nested categories as colored arcs that can be clicked to zoom into sub-hierarchies. Built with D3 v5 and rendered as SVG, the visualization uses `d3.partition`, `d3.hierarchy`, and `d3.arc` to compute layout geometry, with `d3.scaleOrdinal` and `d3.interpolateRainbow` for color mapping. Clicking an arc triggers a smooth 750ms transition via `transition.attrTween` that interpolates angular and radial coordinates, while labels rotate and fade based on visibility thresholds. Ancestor tooltips appear via appended `title` elements.