This area chart displays the average petal length for different flower species, using a green line and translucent fill to highlight the trend across species. The visualization is built with D3.js v7 and renders as an SVG. It loads a CSV dataset, calculates group means with `d3.rollups` and `d3.mean`, then draws the area, line, and data points. Axes are scaled with `d3.scaleBand` and `d3.scaleLinear`, and annotations are added via SVG text elements.