This full-circle radial tree displays a hierarchical breakdown of world countries by continent and subregion, using a JSON dataset. The visualization supports panning and zooming through D3’s `d3.zoom` event handler. The layout is computed with `d3.cluster()` in a 360-degree arrangement, with curved link paths and nodes rendered as SVG circles. Text labels rotate radially to follow branch angles, with font size scaled by depth using `d3.scaleSqrt`. Distinct stroke colors and dash patterns differentiate hierarchy levels.