This example displays a choropleth-style map of the 50 U.S. states, with each state filled in blue and bordered by black interior lines. Built with React and D3 v5, it uses the `geoAlbersUsaTerritories` projection and `d3.geoPath()` to render geographic shapes from a TopoJSON file. The map highlights states on hover by changing their fill color to purple. The data is loaded asynchronously via `json()` and processed with TopoJSON’s `feature` and `mesh` functions.