A fork of a U.S. state map choropleth visualizes state population data using a blue sequential color scale. The visualization loads TopoJSON from the `us-atlas` package and a text file of state populations, parsing both via `Promise.all` and `d3.json`/`d3.text`. It projects boundaries with `d3.geoAlbersUsa` and `d3.geoPath`, and maps FIPS codes to state names via a lookup table. Users inspect values through an HTML tooltip triggered by mouseover, with SVG rendering for all map elements.