This interactive scatterplot shows the relationship between age and BMI, with a gradient-filled area chart highlighting BMI trends and a dashed hover line tracking values across the x-axis. The visualization includes a tooltip that displays the exact age, BMI, and category (High or Normal) for the nearest data point, using a bisector to locate the closest value. Built with D3 v7, it loads CSV data and renders SVG elements, incorporating vertical gridlines, labeled axes, and smooth curve interpolation via the `curveCatmullRom` generator. Hover interactions are managed through mouse events that update the tooltip position and visibility.