An interactive choropleth map of New York State displays its counties, which change color and reveal a tooltip with the county name on hover. Clicking a county hides all others and shows a full-width “Return” button, though the code’s data-entry section is empty, so no additional details appear. Built with D3 v7 and topojson, it uses `d3.geoMercator`, `d3.geoPath`, and `d3.geoBounds` to project and render GeoJSON/TopoJSON data, with SVG paths styled via CSS.