This example displays sales, revenue, and profit trends from a CSV file using two D3.js v7 charts: a multi-series line chart and a combined bar-and-line chart. It uses `d3.csv`, `d3.scaleTime`, `d3.line`, and `d3.axisBottom` for data loading, scaling, and rendering, with tooltips via `d3.select` and a Poppins font for typography.