Line Chart multiple lines | interractive Legend
This interactive visualization displays temperature readings for multiple cities over the course of a week as distinct colored line paths. Users can click either the color legend entries or the lines themselves to isolate or deselect a specific city, with non-selected paths dimming to 20% opacity. The line generator uses d3.curveBasis for smooth interpolation, while scaleTime and scaleLinear map timestamps and temperatures. The color legend is custom-built with circle and text elements, and the data comes from a CSV file loaded via d3.csv.