styling-system
Load PROACTIVELY when task involves CSS architecture, theming, or visual design systems. Use when user says \"set up Tailwind\", \"add dark mode\", \"create a design system\", \"make it responsive\", or \"configure the theme\". Covers Tailwind configuration and custom plugins, design token systems, responsive breakpoint strategies, dark mode implementation, component variant patterns (CVA/class-variance-authority), CSS-in-JS alternatives, and animation patterns.