This interactive collapsible tree visualizes the hierarchical structure of the Flare dataset. Users can click on any node to expand or collapse its children, revealing the nested organization of the data. The visualization uses D3.js v6 to compute the tree layout and renders nodes and links as SVG elements. Transitions between states are animated, and the view automatically adjusts to fit the visible portion of the tree. The hierarchical data is loaded from an external JSON file, and the layout dynamically recalculates as the tree structure changes.