This multi-series line chart displays Sales and Profit trends over time, with two lines drawn in steel blue and green on a shared axis. The visualization uses D3.js v7, loading CSV data from a GitHub gist and mapping numeric Day, Sales, and Profit fields. The code employs `d3.csv`, `d3.scaleLinear`, `d3.line`, and `d3.axisBottom`/`d3.axisLeft` to construct the SVG rendering, including labeled axes and a title.