This area chart displays monthly sales growth from January 2021 through January 2025, showing a steady upward trend in units sold. The D3.js v6 visualization uses `d3.area()` with `d3.curveMonotoneX` to render a smooth filled path, with lightsteelblue fill and steelblue stroke. The code loads data from a CSV file via `d3.csv()`, parses dates with `d3.timeParse()`, and constructs time and linear scales using `d3.scaleTime()` and `d3.scaleLinear()`. Grid lines are added through custom axis configurations, while rotated month labels and axis titles provide context. The SVG output includes a white background, rounded corners, and a subtle shadow effect.