This pie chart displays the percentage share of smartphone brands or models from a CSV file loaded from GitHub, with slices sized proportionally to each category’s value. The visualization renders slices using D3’s `d3.pie` and `d3.arc`, with percentage labels positioned via `arcLabel.centroid` and a supplementary legend constructed from SVG rects and texts. Data is processed using helper functions that detect label and value columns, filter null entries, and normalize sums exceeding 100 into percentages. The chart uses D3 v7’s `d3.csv` fetch, `d3.rollup` for counting, and `d3.scaleOrdinal` with the Tableau10 color scheme for categorical coloring.