Line Chart with Multiple Lines
This line chart displays one week of temperature readings in degrees Celsius across multiple cities, with each city represented by a distinct colored line. The chart uses d3.line with curveBasis for smooth curves, d3.scaleTime for the time axis, d3.scaleLinear for temperature, and d3.scaleOrdinal with schemeCategory10 for city colors. Data is loaded via d3.csv from the Data Canvas - Sense Your City dataset, parsed into timestamp and temperature values, then nested by city using d3.nest. A custom colorLegend module renders the legend, while the chart includes axis labels, gridlines, and a title.