Three bar charts of synthetic categorical data react to two toggle buttons labeled "Taxis" and "Personenautos." Clicking either button triggers an animated update that linearly transitions the bar heights over one second, swapping between the two predefined datasets. The visualization uses D3 v5, building the SVG with `d3.scaleBand`, `d3.scaleLinear`, and `d3.axisBottom`/`d3.axisLeft`, while a custom `update` function leverages `.transition().duration()` to smoothly change rectangle geometries.