This interactive visualization displays a hierarchical circular packing diagram of the Flare software project's class structure, where nested circles represent parent-child relationships and their sizes encode the relative code volume. Built with D3.js v4 within a React framework, the SVG-based animation supports zooming and panning through the `d3.pack` layout algorithm. The visualization uses smooth transitions via `d3.transition` to animate between hierarchy levels, with color gradients applied based on depth using `d3.scaleLinear`. Users click on circles to explore the tree, while labels fade in and out to show only the currently focused level.