This interactive tree diagram visualizes a decision tree for classifying Iris flowers based on petal measurements. It shows hierarchical split rules and resulting class distributions at leaf nodes. The visualization uses D3.js v4 with SVG rendering and animated transitions, implementing a collapsible tree layout where nodes can be clicked to expand or collapse branches. The code employs `d3.hierarchy`, custom transition methods, and a durational animation to smoothly reposition nodes and links when the tree state changes.