tailwind-design-system

/* 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;
  }
}

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

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

Base styles → Variants → Sizes → States → Overrides