Tailwind Design System

Tailwind Design System (v4)

Build production-ready design systems with Tailwind CSS v4, including CSS-first configuration, design tokens, component variants, responsive patterns, and accessibility.

Note: This skill targets Tailwind CSS v4 (2024+). For v3 projects, refer to the upgrade guide.

When to Use This Skill

• Creating a component library with Tailwind v4
• Implementing design tokens and theming with CSS-first configuration
• Building responsive and accessible components
• Standardizing UI patterns across a codebase
• Migrating from Tailwind v3 to v4
• Setting up dark mode with native CSS features

Key v4 Changes

Quick Start

/* app.css - Tailwind v4 CSS-first configuration */
@import "tailwindcss";

/* Define your theme with @theme */
@theme {
  /* Semantic color tokens using OKLCH for better color perception */
  --color-background: oklch(100% 0 0);
  --color-foreground: oklch(14.5% 0.025 264);

  --color-primary: oklch(14.5% 0.025 264);
  --color-primary-foreground: oklch(98% 0.01 264);

  --color-secondary: oklch(96% 0.01 264);
  --color-secondary-foreground: oklch(14.5% 0.025 264);

  --color-muted: oklch(96% 0.01 264);
  --color-muted-foreground: oklch(46% 0.02 264);

  --color-accent: oklch(96% 0.01 264);
  --color-accent-foreground: oklch(14.5% 0.025 264);

  --color-destructive: oklch(53% 0.22 27);
  --color-destructive-foreground: oklch(98% 0.01 264);

  --color-border: oklch(91% 0.01 264);
  --color-ring: oklch(14.5% 0.025 264);

  --color-card: oklch(100% 0 0);
  --color-card-foreground: oklch(14.5% 0.025 264);

  /* Ring offset for focus states */
  --color-ring-offset: oklch(100% 0 0);

  /* Radius tokens */
  --radius-sm: 0.25rem;
  --radius-md: 0.375rem;
  --radius-lg: 0.5rem;
  --radius-xl: 0.75rem;

  /* Animation tokens - keyframes inside @theme are output when referenced by --animate-* variables */
  --animate-fade-in: fade-in 0.2s ease-out;
  --animate-fade-out: fade-out 0.2s ease-in;
  --animate-slide-in: slide-in 0.3s ease-out;
  --animate-slide-out: slide-out 0.3s ease-in;

  @keyframes fade-in {
    from {
      opacity: 0;
    }
    to {
      opacity: 1;
    }
  }

  @keyframes fade-out {
    from {
      opacity: 1;
    }
    to {
      opacity: 0;
    }
  }

  @keyframes slide-in {
    from {
      transform: translateY(-0.5rem);
      opacity: 0;
    }
    to {
      transform: translateY(0);
      opacity: 1;
    }
  }

  @keyframes slide-out {
    from {
      transform: translateY(0);
      opacity: 1;
    }
    to {
      transform: translateY(-0.5rem);
      opacity: 0;
    }
  }
}

/* Dark mode variant - use @custom-variant for class-based dark mode */
@custom-variant dark (&:where(.dark, .dark *));

/* Dark mode theme overrides */
.dark {
  --color-background: oklch(14.5% 0.025 264);
  --color-foreground: oklch(98% 0.01 264);

  --color-primary: oklch(98% 0.01 264);
  --color-primary-foreground: oklch(14.5% 0.025 264);

  --color-secondary: oklch(22% 0.02 264);
  --color-secondary-foreground: oklch(98% 0.01 264);

  --color-muted: oklch(22% 0.02 264);
  --color-muted-foreground: oklch(65% 0.02 264);

  --color-accent: oklch(22% 0.02 264);
  --color-accent-foreground: oklch(98% 0.01 264);

  --color-destructive: oklch(42% 0.15 27);
  --color-destructive-foreground: oklch(98% 0.01 264);

  --color-border: oklch(22% 0.02 264);
  --color-ring: oklch(83% 0.02 264);

  --color-card: oklch(14.5% 0.025 264);
  --color-card-foreground: oklch(98% 0.01 264);

  --color-ring-offset: oklch(14.5% 0.025 264);
}

/* Base styles */
@layer base {
  * {
    @apply border-border;
  }

  body {
    @apply bg-background text-foreground antialiased;
  }
}

Core Concepts

1. Design Token Hierarchy

Brand Tokens (abstract)
    └── Semantic Tokens (purpose)
        └── Component Tokens (specific)

Example:
    oklch(45% 0.2 260) → --color-primary → bg-primary

2. Component Architecture

Base styles → Variants → Sizes → States → Overrides

Patterns

Pattern 1: CVA (Class Variance Authority) Components

// components/ui/button.tsx
import { Slot } from '@radix-ui/react-slot'
import { cva, type VariantProps } from 'class-variance-authority'
import { cn } from '@/lib/utils'

const buttonVariants = cva(
  // Base styles - v4 uses native CSS variables
  'inline-flex items-center justify-center whitespace-nowrap rounded-md text-sm font-medium transition-colors focus-visible:outline-none focus-visible:ring-2 focus-visible:ring-ring focus-visible:ring-offset-2 disabled:pointer-events-none disabled:opacity-50',
  {
    variants: {
      variant: {
        default: 'bg-primary text-primary-foreground hover:bg-primary/90',
        destructive: 'bg-destructive text-destructive-foreground hover:bg-destructive/90',
        outline: 'border border-border bg-background hover:bg-accent hover:text-accent-foreground',
        secondary: 'bg-secondary text-secondary-foreground hover:bg-secondary/80',
        ghost: 'hover:bg-accent hover:text-accent-foreground',
        link: 'text-primary underline-offset-4 hover:underline',
      },
      size: {
        default: 'h-10 px-4 py-2',
        sm: 'h-9 rounded-md px-3',
        lg: 'h-11 rounded-md px-8',
        icon: 'size-10',
      },
    },
    defaultVariants: {
      variant: 'default',
      size: 'default',
    },
  }
)

export interface ButtonProps
  extends React.ButtonHTMLAttributes<HTMLButtonElement>,
    VariantProps<typeof buttonVariants> {
  asChild?: boolean
}

// React 19: No forwardRef needed
export function Button({
  className,
  variant,
  size,
  asChild = false,
  ref,
  ...props
}: ButtonProps & { ref?: React.Ref<HTMLButtonElement> }) {
  const Comp = asChild ? Slot : 'button'
  return (
    <Comp
      className={cn(buttonVariants({ variant, size, className }))}
      ref={ref}
      {...props}
    />
  )
}

// Usage
<Button variant="destructive" size="lg">Delete</Button>
<Button variant="outline">Cancel</Button>
<Button asChild><Link href="/home">Home</Link></Button>

Pattern 2: Compound Components (React 19)

// components/ui/card.tsx
import { cn } from '@/lib/utils'

// React 19: ref is a regular prop, no forwardRef
export function Card({
  className,
  ref,
  ...props
}: React.HTMLAttributes<HTMLDivElement> & { ref?: React.Ref<HTMLDivElement> }) {
  return (
    <div
      ref={ref}
      className={cn(
        'rounded-lg border border-border bg-card text-card-foreground shadow-sm',
        className
      )}
      {...props}
    />
  )
}

export function CardHeader({
  className,
  ref,
  ...props
}: React.HTMLAttributes<HTMLDivElement> & { ref?: React.Ref<HTMLDivElement> }) {
  return (
    <div
      ref={ref}
      className={cn('flex flex-col space-y-1.5 p-6', className)}
      {...props}
    />
  )
}

export function CardTitle({
  className,
  ref,
  ...props
}: React.HTMLAttributes<HTMLHeadingElement> & { ref?: React.Ref<HTMLHeadingElement> }) {
  return (
    <h3
      ref={ref}
      className={cn('text-2xl font-semibold leading-none tracking-tight', className)}
      {...props}
    />
  )
}

export function CardDescription({