d3-charts

Create interactive, production-grade charts with D3.js. Use this skill when the user asks to build D3.js visualizations including scatter plots, pie/donut charts, bar charts, bar chart races, line charts, line chart races, heatmaps, treemaps, or any SVG-based data visualization. Covers animated entry transitions, keyframe animations, progressive line reveals, hierarchical layouts, sequential color scales, theme-aware color schemes (with custom Streamlit-inspired palettes), tooltips, legends, and responsive design. Generates polished, accessible code that avoids generic AI aesthetics.