This dark-themed area chart visualizes the average monthly listeners of top Spotify artists grouped by their debut year. The chart uses a blue gradient-filled area with a lighter line overlay, and interactive data points display exact values via a tooltip on hover. Built with D3 v7, it loads CSV data, aggregates it with `d3.rollup` and `d3.mean`, and renders the visualization using SVG paths generated by `d3.area` and `d3.line`.