This example demonstrates a zoomable world map with country outlines and hover highlighting, rendered as SVG. The map uses D3's `geoNaturalEarth1` projection and `geoPath` to draw country shapes from the world-atlas TopoJSON dataset, with a sphere background. Interactive zoom is implemented via D3's `zoom` module, which applies a transform to the map group on zoom events. Country names are joined from TSV data, and hovering over a country fills it red via CSS `.country:hover`. The visualization is built with React and D3 v5.