This example displays a world map colored by values joined from a CSV dataset, with a hover tooltip showing each country’s name and numeric value. It renders an SVG using D3 v7’s `d3.geoNaturalEarth1` projection and `d3.geoPath`, loading country boundaries from TopoJSON via `world-atlas`. Country colors are assigned through a sequential `d3.scaleSequential` interpolator, while the CSV is joined using a `Map`. The tooltip appears on mouseover events, positioned at the cursor.