This line chart displays sales volume over time for multiple districts, using distinct colors to differentiate each district’s trend. The visualization uses D3 v5 with SVG rendering, employing `scaleTime` and `scaleLinear` for axes, `line` with `curveBasis` for smoothed paths, and `nest` to group data by district. Data comes from a CSV file parsed with dayjs. A custom `colorLegend` function renders the color key, and axis labels and a title annotate the chart.