This map visualizes Swedish counties, with each region filled in teal and interior borders highlighted in cyan. The data originates from a TopoJSON file of simplified Swedish county boundaries. Built with React and D3 v5, the visualization uses `geoMercator` projection and `geoPath` to render the geographic features and mesh outlines. The projection is fitted to the specified extent using `fitExtent`, and the map is drawn as SVG paths within a React component.