My first Line Chart temperature
This line chart visualizes temperature trends across multiple cities over a week, with each city represented as a colored line and a legend identifying the color mapping. The visualization uses D3 v5 APIs including `scaleTime`, `scaleLinear`, `scaleOrdinal`, `line` with `curveBasis`, and `nest` to group data by city, while `axisBottom` and `axisLeft` render labeled axes. Data is loaded from a CSV file using `d3.csv`. The chart is rendered as SVG with an animated color legend that transitions its appearance over one second, and the code includes a working example using temperature data from Data Canvas.