This bubble chart visualizes the relationship between age and BMI for approximately 250 individuals, with circle size encoding insurance charges and color distinguishing gender. Built with D3 v7 in a React-agnostic HTML page, it uses `d3.scaleLinear` for both axes, `d3.scaleOrdinal` for male/female coloring, and `Math.sqrt` to map charges to radius. Data loads asynchronously from a CSV file via `d3.csv`, and the SVG rendering includes custom axes, labels, and a legend showing size and color ranges.