This D3.js v7 dashboard analyzes synthetic BMW vehicle sales data loaded from a CSV file, presenting six interactive chart types that users can toggle between using dropdown filters. The interface displays summary cards, insight metrics, and region-filtered visualizations including stacked bar charts of model sales by year, line charts of regional sales trends, an area chart of average prices, donut chart of price classifications, and horizontal bar rankings. All charts support hover tooltips with boundary-checked positioning, legend filtering, and click-to-open modal magnification with keyboard escape functionality. The dashboard adapts responsively across desktop, tablet, and mobile breakpoints.