This example visualizes 2023 sales data for different product categories as an interactive pie chart, paired with a color-coded legend. Using D3.js (v7), it loads CSV data via the `d3.csv` method and renders the chart with `d3.pie` and `d3.arc`. The chart employs a categorical color scale (`d3.scaleOrdinal` with `schemeCategory10`) for slices and legend items. Hover interactions display a tooltip showing the sales value in billions, with transitions controlling tooltip opacity. The layout places the legend on the left and the pie chart on the right within separate SVG containers.