What problem does it solve? Building custom charts, network diagrams, or geographic visualisations from scratch requires deep knowledge of d3.js scales, layouts, and DOM binding patterns, which slows down development of bespoke visualisations beyond standard charting libraries. ## Core Features & Use Cases - Chart Pattern Library: Ready-to-adapt code for bar, line, scatter, pie, heatmap, chord, treemap, sunburst, and force-directed network diagrams. - Interactivity & Animation: Patterns for tooltips, zoom, pan, brush selection, drag, and choreographed transitions. - Scale & Colour References: Detailed guides covering linear, log, time, band, ordinal, sequential, and diverging scales plus colour-blind-safe palettes. - Use Case: A developer needs a custom heatmap with a colour legend and responsive resizing in a React dashboard; the skill provides the full drawing function, scale setup, and ResizeObserver pattern to adapt. ## Quick Start Ask the AI to create an interactive d3.js bar chart with tooltips and responsive sizing from your dataset.