---
id: wiki-2026-0508-tailwind-css-v4
title: Tailwind CSS v4
category: 10_Wiki/Topics
status: verified
canonical_id: self
aliases: [Tailwind v4, TailwindCSS 4, Tailwind 4.x]
duplicate_of: none
source_trust_level: A
confidence_score: 0.95
verification_status: applied
tags: [css, tailwind, frontend, styling, lightning-css]
raw_sources: []
last_reinforced: 2026-05-10
github_commit: pending
tech_stack:
  language: css
  framework: tailwindcss-v4
---

# Tailwind CSS v4

## 매 한 줄
> **"매 Tailwind v4 는 CSS-first 의 rebuild — JS config 의 retire, Lightning CSS engine, 5x faster build"**. 매 2025 Q1 stable release. 매 v3 의 `tailwind.config.js` → v4 의 `@theme {}` CSS-native. 매 modern CSS feature (cascade layers, container queries, color-mix, @starting-style) 의 first-class 의 support.

## 매 핵심

### 매 v4 의 break (vs v3)
- **JS config retired**: `tailwind.config.js` → `@theme` directive in CSS.
- **PostCSS plugin → dedicated**: `@tailwindcss/postcss` or Vite plugin (`@tailwindcss/vite`).
- **Lightning CSS engine**: Rust-based, 5x faster, native vendor prefixing + nesting.
- **Single CSS import**: `@import "tailwindcss";` (replaces 3-line directives).
- **Auto content detection**: heuristic-based, manual `content: [...]` 의 unnecessary in most cases.
- **CSS variables for everything**: theme tokens 의 `--color-blue-500` 등 native CSS var.
- **Container queries**: built-in `@container` utility.
- **3D transforms, color-mix(), @starting-style**: modern CSS feature 의 utility.

### 매 install (2026)
```bash
# Vite
npm install tailwindcss @tailwindcss/vite
# PostCSS
npm install tailwindcss @tailwindcss/postcss
# CLI
npm install tailwindcss @tailwindcss/cli
```

### 매 응용
1. **Next.js 15 / Remix / SvelteKit**: Vite plugin 의 default.
2. **Design system**: `@theme` 의 token export → tailwind + native CSS 의 share.
3. **Container query layout**: 매 truly responsive component.

## 💻 패턴

### 1. CSS-first config (`app.css`)
```css
@import "tailwindcss";

@theme {
  --color-brand-50:  oklch(97% 0.02 250);
  --color-brand-500: oklch(60% 0.18 250);
  --color-brand-900: oklch(20% 0.06 250);

  --font-display: "Inter Display", "ui-sans-serif", system-ui;

  --radius-lg: 14px;
  --spacing-section: 5rem;

  --breakpoint-3xl: 1920px;
}

/* Custom variants */
@custom-variant dark (&:where(.dark, .dark *));
```

### 2. Vite integration (`vite.config.ts`)
```typescript
import { defineConfig } from "vite";
import tailwindcss from "@tailwindcss/vite";

export default defineConfig({
  plugins: [tailwindcss()],
});
```

### 3. Container queries
```html
<div class="@container">
  <article class="grid grid-cols-1 @md:grid-cols-2 @xl:grid-cols-3">
    <!-- responds to parent .@container, NOT viewport -->
  </article>
</div>
```

### 4. Dark mode (CSS-first)
```css
/* app.css */
@variant dark (&:where(.dark, .dark *));
```
```html
<html class="dark">
  <body class="bg-white dark:bg-zinc-950 text-zinc-900 dark:text-zinc-100">
    ...
  </body>
</html>
```

### 5. Arbitrary values + CSS vars
```html
<!-- Direct theme token reference -->
<div class="bg-(--color-brand-500) text-(--color-brand-50)">...</div>

<!-- Arbitrary -->
<div class="grid-cols-[repeat(auto-fit,minmax(220px,1fr))]">...</div>
```

### 6. 3D transform utilities (v4 new)
```html
<div class="perspective-distant">
  <div class="rotate-x-25 rotate-y-15 rotate-z-5 translate-z-10
              transform-3d hover:rotate-y-0 transition-transform duration-500">
    Card
  </div>
</div>
```

### 7. `@starting-style` (entry animation)
```css
@layer components {
  .modal {
    @apply opacity-100 translate-y-0 transition-[opacity,translate] duration-300;
    @starting-style {
      opacity: 0;
      translate: 0 1rem;
    }
  }
}
```

### 8. Custom utility / component
```css
@utility tab-* {
  tab-size: --value(integer);
}

@utility content-auto {
  content-visibility: auto;
}

/* usage: class="tab-4 content-auto" */
```

### 9. Migration from v3
```bash
# Official codemod
npx @tailwindcss/upgrade@latest

# checks: deprecated utility renames, config → @theme conversion,
# @tailwind base/components/utilities → @import "tailwindcss"
```

## 매 결정 기준
| 상황 | Approach |
|---|---|
| New project (2026) | v4 직행 |
| v3 → v4 migration | `@tailwindcss/upgrade` codemod |
| JS config 의 deeply nested logic | v3 유지 or 매 partial migration |
| Vite/Next 15+ | `@tailwindcss/vite` |
| Legacy webpack | `@tailwindcss/postcss` |

**기본값**: 매 new project 의 v4 + Vite plugin + `@theme` CSS-first config.

## 🔗 Graph
- 부모: [[Tailwind-CSS]]
- 변형: [[Container-Queries]]
- 응용: [[Next.js]] · [[Design-System]] · [[Component-Library]]
- Adjacent: [[Lightning-CSS]]

## 🤖 LLM 활용
**언제**: utility class composition, migration codemod 의 explain, custom `@utility` 의 design.
**언제 X**: 매 visual judgment (color, spacing, hierarchy) 매 human eye 의 final.

## ❌ 안티패턴
- **v4 에서 v3 식 `tailwind.config.js` 의 keep**: 매 partial work — 매 `@theme` 의 migrate.
- **`@apply` overuse**: 매 utility 의 advantage 의 lose. 매 component 의 truly repeated 일 때만.
- **Manual `content: [...]` 의 v4 에서 의무화**: 매 auto-detection 의 trust (special case 만 add).
- **`@import "tailwindcss/utilities"` 분리**: v4 에서 single `@import "tailwindcss";` 의 sufficient.
- **Hard-coded color hex 의 spam**: 매 `@theme` token 의 사용.

## 🧪 검증 / 중복
- Verified (Tailwind v4.0 release notes Jan 2025, official migration guide, Adam Wathan blog).
- 신뢰도 A.

## 🕓 Changelog
| 날짜 | 변경 |
|---|---|
| 2026-05-08 | Phase 1 |
| 2026-05-10 | Manual cleanup — Tailwind v4 (CSS-first, Lightning CSS, modern features) full canonical |
