Cheap tricks for interaction
This example displays a world map using a natural Earth projection, with countries rendered as green SVG paths with black strokes against a dark blue sphere. Hovering over any country turns it red, providing a simple interaction cue. The visualization is built with D3 v5, using `d3.geoPath` and `d3.geoNaturalEarth1` for geographic projection, while geographic data comes from the TopoJSON world-atlas countries-110m dataset, which is parsed with `topojson.feature` and loaded via `d3.json`.