This interactive sunburst diagram visualizes the hierarchical structure of the Flare dataset, with each ring segment representing a category or subcategory whose arc width corresponds to its value. Users can click on any node to zoom into that branch, smoothly animating the re-scaling of arcs and labels via D3 transitions. The visualization is rendered as SVG and uses `d3.hierarchy`, `d3.partition`, and `d3.arc` to compute layout, while `d3.interpolateRainbow` assigns categorical colors by top-level branch. The code loads data asynchronously through the Observable Standard Library’s `require()` function.