This is a static tree diagram showing the hierarchical structure of World, Continents, and Countries. The root node (World) is blue, continents are purple, and country leaf nodes are green, with a color-coded legend on the right. The visualization uses the D3.js v7 `d3.tree()` layout, `d3.hierarchy()`, and `d3.linkVertical()` to compute and draw the SVG paths and circles. The data is a hardcoded JavaScript object representing the geographic parent-child relationships.