This example visualizes a stacked bar chart of traffic categories—pedestrians, non-motorized vehicles, and motor vehicles—across a single crosswalk lane. A stacked series shows each category’s count as a colored segment, with the total height representing the overall value. The visualization uses D3 v6’s `d3.stack()` to transform the data into stacked series, `d3.scaleBand()` for the categorical x-axis, and `d3.scaleLinear()` for the y-axis. It renders as an SVG, with a custom legend built from D3 selections and color mapping via `d3.scaleOrdinal()` with `d3.schemeSet3`.