This D3 v5 zoomable sunburst visualizes a hierarchical dataset, using colored arcs to represent nested categories from the flare data loaded via the Observable standard library. Clicking an arc animates a zoom into that node, with transitions driven by `d3.arc` interpolation and `transition.attrTween` to smoothly reshape arcs and labels. The SVG rendering uses `d3.partition`, `d3.hierarchy`, and ordinal color scales, with visibility logic filtering arcs and text based on computed angular and radial bounds.