This choropleth map visualizes county-level population estimates across the United States, with each county colored on a sequential green scale from light (approximately 900 people) to dark (up to 4 million). The map is rendered as SVG using React, with geographic boundaries drawn via `d3.geoPath` and an equirectangular projection. Population data, loaded from a local CSV file, is joined to county features by name, and counties lacking data appear in gray. The map supports interactive zooming through `d3.zoom`, transforming the SVG paths in response to user gestures.