This interactive tree diagram visualizes a hierarchical breakdown of an automobile, starting with the root node “VEHICLE” and branching into categories like Engine, Interior, and Body, with further subcomponents such as RPM, Seats, and Mirrors. Built with D3.js (version 3.5.17), the layout uses the `d3.layout.tree` and `d3.svg.diagonal` APIs to position nodes and draw curved links. Rendered as an SVG with animated transitions, clicking a node collapses or expands its children. Node colors reflect the data’s “level” field, while the styling is defined via CSS.