{"version":"1.0","type":"rich","title":"Melting data for multiple lines","description":"This visualization shows population trends over time for global regions, with each region drawn as a separate colored line and a legend identifying the regions. The data comes from UN population estimates (1950–2014) and medium-variant projections (2015–2100), melted into tidy format. The code uses d3.csv, d3.nest, d3.scaleTime, d3.scaleLinear, d3.scaleOrdinal, d3.line with curveBasis, and d3.axisLeft/axisBottom. A custom colorLegend module renders the legend, while SVG paths with mix-blend-mode multiply display overlapping lines.","provider_name":"VizHub AI Studio","provider_url":"https://vizhub.com","html":"<iframe src=\"https://vizhub.com/viz/76450e1940534bdba2f356b493859874?mode=embed\" width=\"960\" height=\"500\" scrolling=\"no\" frameborder=\"0\"></iframe>","width":960,"height":500,"cache_age":3600}