This choropleth displays Japan’s land features and internal administrative boundaries using a natural Earth projection. The visualization renders geographic shapes via `d3.geoPath` and `geoNaturalEarth1`, with topojson data from the Japan Atlas. Landmasses appear in teal, interiors in light gray, and a graticule overlays the sphere. React manages the component state, loading the dataset through `useData` and `d3.json`. The stylized palette and minimal layout emphasize the spatial distribution of Japan’s regions.