This interactive choropleth displays the contiguous United States and territories, with each state path filled in yellow and outlined in blue. Hovering over a state turns it green and reveals its name via a tooltip. The map uses D3 v5’s `geoAlbersUsa` projection with `geoPath` to render TopoJSON data from a GitHub gist, while TopoJSON’s `feature` API converts the TopoJSON objects into GeoJSON features for binding to SVG path elements. State names come from the `properties.name` field.