Shadcn Guideline: Chart — Define chart config. Description: Create chartConfig for consistent theming. Do: chartConfig with color definitions. Don't: Inline colors in charts. Good Example: { desktop: { label: "Desktop", color: "#2563eb" } }. Bad Example: <Bar fill="#2563eb"/>. Severity: Medium. Docs: https://ui.shadcn.com/docs/components/chart.