This visualization pairs a choropleth map with a scatterplot to explore Tour de France rider data. The map shades countries by the number of riders, while the scatterplot plots winning margin against year. Hovering over either a country or a rider dot highlights corresponding elements across both views using shared IDs and D3 selections. The code uses `d3.geoEqualEarth` and `d3.geoPath` for the map, with SVG rendering driven by `d3.csv` and `d3.json` data loading.