This visualization shows the hierarchical structure of world countries organized by continent and subregion, with each country labeled as a leaf node in a tidy tree layout. The tree radiates horizontally from a root node, with font sizes decreasing at deeper levels and country names displayed after their parent regions. Using D3 v5, the implementation applies `d3.tree()` and `d3.hierarchy()` to compute node positions, `d3.linkHorizontal()` to generate curved link paths, and SVG rendering with pan-and-zoom support via `d3.zoom()`. The data comes from a pre-structured JSON file, and text elements include a glow effect via CSS `text-shadow` for readability.