This treemap visualizes the number of arriving passenger counts (APC) for international airlines at San Francisco International Airport, using data loaded from a CSV file. The hierarchy is built with `d3.stratify`, with airline names as leaf nodes under a single "Origin" parent, and rectangle sizes are computed via `d3.treemap`. Each leaf is rendered as an SVG `<rect>` filled with dark teal and labeled with the airline name using white SVG text. The visualization uses D3 v4 and renders a static, 1500-by-1500-pixel SVG layout with black strokes around each cell.