{"version":"1.0","type":"rich","title":"Circles on a map","description":"This example displays a natural Earth projection world map with semi-transparent teal circles overlaid on each country, sized by 2018 population data from the UN. Country boundaries are drawn using `d3.geoPath` and TopoJSON, while missing population values appear as pink regions. A `d3.scaleSqrt` maps population to circle radius, and a custom legend shows the scale. The map supports pan and zoom via `d3.zoom`, with circle positioning computed from `d3.geoCentroid` and projected coordinates.","provider_name":"VizHub AI Studio","provider_url":"https://vizhub.com","html":"<iframe src=\"https://vizhub.com/viz/727ded7fecc243abaa886f397653949a?mode=embed\" width=\"960\" height=\"500\" scrolling=\"no\" frameborder=\"0\"></iframe>","width":960,"height":500,"cache_age":3600}