This map displays air quality index (AQI) readings as circles overlaid on a U.S. states map, with circle size proportional to AQI values. It renders SVG via React, using d3.geoPath with a geoAlbersUsa projection for the map outlines and d3.scaleSqrt to map AQI to radii. The data is loaded as CSV from a GitHub gist, while state boundaries come from the us-atlas TopoJSON. Hovering over a circle shows a tooltip with its AQI value.