# Tailwind > Tailwind CSS v4 with shadcn/ui — setup, configuration, component patterns, dark mode, and troubleshooting. Use when setting up Tailwind v4, building UI components, fixing Tailwind errors, migrating from v3, or styling with utility classes. - Skill: `hjewkes/tailwind` (Agent Skill, multi-file: 10 files) - Install (CLI): `npx skillmds@latest add hjewkes/tailwind` - Raw SKILL.md: https://api.skillmd.com/api/skills/hjewkes/tailwind/raw - Safety review: pending - Works with: Claude Code, Claude.ai, OpenAI Codex - Category: Web & Frontend - Author: hjewkes (https://skillmd.com/u/hjewkes) - Updated: 2026-09-17 - Page: https://skillmd.com/skills/hjewkes/tailwind --- # Tailwind CSS v4 Combined from jezweb/claude-skills (tailwind-v4-shadcn + tailwind-patterns). Production-tested. ## Setup Quick Start ```bash pnpm add tailwindcss @tailwindcss/vite pnpm add -D @types/node tw-animate-css pnpm dlx shadcn@latest init rm tailwind.config.ts # v4 doesn't use this ``` Use `@tailwindcss/vite` plugin (NOT PostCSS). Set `"config": ""` in `components.json`. ## The Four-Step CSS Architecture Skip any step and the theme breaks. See `references/setup.md` for full details. 1. **CSS Variables at `:root`** — define colors with `hsl()` wrapper, NOT inside `@layer base` 2. **`@theme inline`** — map CSS vars to Tailwind utilities (`--color-background: var(--background)`) 3. **`@layer base`** — apply base styles using unwrapped variables 4. **Result** — `bg-background` auto-switches in dark mode, no `dark:` prefix needed ## Critical Rules **Always**: semantic tokens (`bg-primary` not `bg-blue-500`), mobile-first (`base → sm: → md:`), `hsl()` in `:root`/`.dark`, consistent spacing (4/6/8/12/16/24 scale) **Never**: `tailwind.config.ts` (v4 ignores it), `@apply` with `@layer` classes (use `@utility`), double-wrap `hsl(var(--color))`, raw colors, `.dark { @theme {} }`, `dark:` variants for semantic colors ## Quick Error Reference | Symptom | Fix | |---------|-----| | `bg-primary` doesn't work | Add `@theme inline` block | | Colors black/white | Remove double `hsl()` wrap | | Dark mode stuck | Add ThemeProvider, check `.dark` on `` | | Build fails | Delete `tailwind.config.ts` | | Animation errors | Replace `tailwindcss-animate` with `tw-animate-css` | | `@apply` breaks | Use `@utility` directive instead | | Base styles ignored | Don't wrap in `@layer base`, define at root | Full error details with solutions: `references/common-errors.md` ## Component Patterns Patterns use semantic tokens for automatic dark mode. See `references/patterns.md` for full library. ```tsx // Container
// Responsive grid
// Card
// Button