Read in JSON department files
This example shows a zoomable, animated sunburst diagram that visualizes male and female student counts across courses and modules within three academic departments. Users can filter the view to a specific department via radio buttons, which transitions the hierarchy in response. Built with D3 v5, the visualization loads three JSON files and uses `d3.hierarchy`, `d3.partition`, and `d3.arc` to render the radial layout, with color encoding by department and hover tooltips revealing structural details.