A zoomable treemap visualizes crime data from a JSON hierarchy, with rectangles sized by offense counts and colored by rate of change from blue (negative) to red (positive). Users click parent nodes to drill down between broad categories like violent and non-violent crimes, while hover effects reveal child rectangles. The implementation uses `d3.treemap`, `d3.hierarchy`, and `d3.scaleLinear` for color, rendering animated transitions via D3 v4 in React with SVG. A separate `flare.json` dataset and parsed `friends.js` array are included but not shown in the main chart.