/* Design System Variables */

:root {
  /* Colors - Pure Greyscale */
  --color-background: #FFFFFF;
  --color-surface: #FFFFFF;
  --color-text-primary: #0A0A0A;
  --color-text-secondary: #3A3A3A;
  --color-text-tertiary: #6B6B6B;
  --color-accent: #000000;
  --color-accent-hover: rgba(0, 0, 0, 0.8);
  --color-border: #E0E0E0;
  --color-border-light: #F0F0F0;

  /* Typography */
  --font-sans: system-ui, -apple-system, 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;
  --font-serif: Georgia, 'Times New Roman', Times, serif;
  --font-mono: ui-monospace, 'SF Mono', 'Cascadia Code', 'Liberation Mono', Menlo, monospace;

  /* Font Sizes */
  --text-xs: 0.75rem;      /* 12px */
  --text-sm: 0.875rem;     /* 14px */
  --text-base: 1rem;       /* 16px */
  --text-lg: 1.125rem;     /* 18px */
  --text-xl: 1.25rem;      /* 20px */
  --text-2xl: 1.5rem;      /* 24px */
  --text-3xl: 1.875rem;    /* 30px */
  --text-4xl: 2.25rem;     /* 36px */
  --text-5xl: 3rem;        /* 48px */

  /* Font Weights */
  --font-regular: 400;
  --font-normal: 400;
  --font-medium: 500;
  --font-semibold: 600;
  --font-bold: 700;

  /* Letter Spacing - For Premium Typography */
  --letter-spacing-tight: -0.02em;
  --letter-spacing-normal: 0;
  --letter-spacing-wide: 0.01em;
  --letter-spacing-wider: 0.025em;
  --letter-spacing-widest: 0.05em;

  /* Line Heights */
  --leading-tight: 1.25;
  --leading-normal: 1.5;
  --leading-relaxed: 1.75;

  /* Spacing Scale (8px base) */
  --space-1: 0.5rem;    /* 8px */
  --space-2: 1rem;      /* 16px */
  --space-3: 1.5rem;    /* 24px */
  --space-4: 2rem;      /* 32px */
  --space-5: 2.5rem;    /* 40px */
  --space-6: 3rem;      /* 48px */
  --space-8: 4rem;      /* 64px */
  --space-10: 5rem;     /* 80px */
  --space-12: 6rem;     /* 96px */
  --space-16: 8rem;     /* 128px */

  /* Layout */
  --max-width-content: 900px;
  --max-width-narrow: 700px;
  --nav-height: 64px;
  --container-padding: var(--space-4);

  /* Borders */
  --border-width: 1px;
  --border-radius-sm: 4px;
  --border-radius-md: 8px;
  --border-radius-lg: 12px;
  --border-radius-full: 9999px;

  /* Shadows */
  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);

  /* Transitions - Enhanced Animation System */
  --transition-fast: 150ms ease;
  --transition-base: 250ms ease;
  --transition-slow: 400ms ease;
  --transition-smooth: 600ms cubic-bezier(0.4, 0, 0.2, 1);

  /* Custom Easing Functions */
  --ease-out-expo: cubic-bezier(0.16, 1, 0.3, 1);
  --ease-in-out-circ: cubic-bezier(0.85, 0, 0.15, 1);

  /* Z-index layers */
  --z-base: 1;
  --z-nav: 100;
  --z-overlay: 200;
  --z-modal: 300;
}

/* Dark mode support (optional for future) */
@media (prefers-color-scheme: dark) {
  :root {
    /* Uncomment to enable dark mode in future */
    /*
    --color-background: #0F0F0F;
    --color-surface: #1A1A1A;
    --color-text-primary: #F5F5F5;
    --color-text-secondary: #D4D4D4;
    --color-text-tertiary: #A3A3A3;
    --color-border: #2C2C2C;
    --color-border-light: #262626;
    */
  }
}