This tree map displays hierarchical data as nested rectangles sized proportionally to their values. The example renders an SVG graphic at 960 by 500 pixels, pulling in D3 v5 from a CDN. The code imports `select` and `arc` from the D3 library, though the visualization logic itself remains minimal in the shown files. The page references a separate stylesheet and JavaScript bundle, with the SVG container set up for the treemap layout. The map is generated using D3’s standard tree-map approach, though the actual data and layout calculations are not explicitly defined in the visible code.