Let's make a face with D3.js!
This example renders a hierarchical dataset of world regions and countries as a horizontal tree, using D3.js v5. The visualization groups countries under regions such as Southern Asia and Western Asia, with text labels sized by depth. The code builds the layout with `d3.tree` and `d3.hierarchy`, draws curved links via `d3.linkHorizontal`, and applies zooming through `d3.zoom`. Data loads from a JSON file, and SVG elements are styled with a custom font and blue stroke.