This visualization displays the hierarchical structure of world countries, organized by continent and subregion using a tree layout. The data is loaded from a JSON file and rendered as an SVG with horizontal links connecting parent and child nodes. Using D3 v5’s `tree`, `hierarchy`, and `linkHorizontal` functions, the code positions labels with font sizes decreasing by depth and includes zoom functionality via `d3.zoom`. Country names are styled with a Playfair Display serif font, and the visualization fills the entire browser window.