This hierarchical tree visualization displays the world’s countries grouped by continent and subregion, using D3’s `d3.tree` layout and `d3.hierarchy` to structure the data. Each node label is rendered as SVG text with font size decreasing by depth, while curved links are drawn using `d3.linkHorizontal`. The chart supports pan and zoom through D3’s `zoom` behavior. Data is loaded from a JSON file, and styling relies on the Playfair Display font.