This interactive tree diagram visualizes the hierarchical relationship between continents, countries, and major cities, using color-coded nodes for each type (e.g., purple for root, green for continents). Rendered as an animated SVG, users can click nodes to expand or collapse branches. The implementation leverages the D3.js `d3.layout.tree` API to compute the layout, with custom CSS classes for node styling and tooltips. The data structure is loaded from an external `Tree.json` file, and the interaction supports zooming and dragging through D3's `d3.behavior.zoom`.