/* ========================================
   EduBridge SA - Design Tokens System
   Phase 5: Modern UI/UX Design Foundation
   ======================================== */

:root {
  /* ========== COLOR PALETTE ========== */

  /* Primary Colors - Education & Trust */
  --color-primary-50: #eff6ff;
  --color-primary-100: #dbeafe;
  --color-primary-200: #bfdbfe;
  --color-primary-300: #93c5fd;
  --color-primary-400: #60a5fa;
  --color-primary-500: #3b82f6;
  --color-primary-600: #2563eb;
  --color-primary-700: #1d4ed8;
  --color-primary-800: #1e40af;
  --color-primary-900: #1e3a8a;
  --color-primary-950: #172554;

  /* Secondary Colors - Success & Growth */
  --color-secondary-50: #f0fdf4;
  --color-secondary-100: #dcfce7;
  --color-secondary-200: #bbf7d0;
  --color-secondary-300: #86efac;
  --color-secondary-400: #4ade80;
  --color-secondary-500: #22c55e;
  --color-secondary-600: #16a34a;
  --color-secondary-700: #15803d;
  --color-secondary-800: #166534;
  --color-secondary-900: #14532d;
  --color-secondary-950: #052e16;

  /* Accent Colors - Highlights & Actions */
  --color-accent-50: #fef7ff;
  --color-accent-100: #fceeff;
  --color-accent-200: #f8d4fe;
  --color-accent-300: #f3b4fc;
  --color-accent-400: #ec84f7;
  --color-accent-500: #e055ee;
  --color-accent-600: #c233d2;
  --color-accent-700: #a025b0;
  --color-accent-800: #83208f;
  --color-accent-900: #6b1e75;
  --color-accent-950: #450a4f;

  /* Neutral Colors - Text & Backgrounds */
  --color-neutral-0: #ffffff;
  --color-neutral-50: #fafafa;
  --color-neutral-100: #f5f5f5;
  --color-neutral-200: #e5e5e5;
  --color-neutral-300: #d4d4d4;
  --color-neutral-400: #a3a3a3;
  --color-neutral-500: #737373;
  --color-neutral-600: #525252;
  --color-neutral-700: #404040;
  --color-neutral-800: #262626;
  --color-neutral-900: #171717;
  --color-neutral-950: #0a0a0a;

  /* Semantic Colors */
  --color-success-50: #f0fdf4;
  --color-success-500: #22c55e;
  --color-success-600: #16a34a;
  --color-success-700: #15803d;

  --color-warning-50: #fffbeb;
  --color-warning-500: #f59e0b;
  --color-warning-600: #d97706;
  --color-warning-700: #b45309;

  --color-error-50: #fef2f2;
  --color-error-500: #ef4444;
  --color-error-600: #dc2626;
  --color-error-700: #b91c1c;

  --color-info-50: #eff6ff;
  --color-info-500: #3b82f6;
  --color-info-600: #2563eb;
  --color-info-700: #1d4ed8;

  /* ========== TYPOGRAPHY ========== */

  /* Font Families */
  --font-primary: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
  --font-secondary: 'Poppins', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --font-mono: 'JetBrains Mono', 'Fira Code', 'Monaco', 'Consolas', monospace;

  /* Font Weights */
  --font-weight-thin: 100;
  --font-weight-extralight: 200;
  --font-weight-light: 300;
  --font-weight-normal: 400;
  --font-weight-medium: 500;
  --font-weight-semibold: 600;
  --font-weight-bold: 700;
  --font-weight-extrabold: 800;
  --font-weight-black: 900;

  /* Font Sizes - Fluid Typography */
  --font-size-xs: clamp(0.75rem, 0.7rem + 0.25vw, 0.875rem);
  --font-size-sm: clamp(0.875rem, 0.8rem + 0.375vw, 1rem);
  --font-size-base: clamp(1rem, 0.9rem + 0.5vw, 1.125rem);
  --font-size-lg: clamp(1.125rem, 1rem + 0.625vw, 1.25rem);
  --font-size-xl: clamp(1.25rem, 1.1rem + 0.75vw, 1.5rem);
  --font-size-2xl: clamp(1.5rem, 1.3rem + 1vw, 1.875rem);
  --font-size-3xl: clamp(1.875rem, 1.6rem + 1.375vw, 2.25rem);
  --font-size-4xl: clamp(2.25rem, 1.9rem + 1.75vw, 3rem);
  --font-size-5xl: clamp(3rem, 2.5rem + 2.5vw, 4rem);
  --font-size-6xl: clamp(3.75rem, 3rem + 3.75vw, 6rem);

  /* Line Heights */
  --line-height-none: 1;
  --line-height-tight: 1.25;
  --line-height-snug: 1.375;
  --line-height-normal: 1.5;
  --line-height-relaxed: 1.625;
  --line-height-loose: 2;

  /* Letter Spacing */
  --letter-spacing-tighter: -0.05em;
  --letter-spacing-tight: -0.025em;
  --letter-spacing-normal: 0em;
  --letter-spacing-wide: 0.025em;
  --letter-spacing-wider: 0.05em;
  --letter-spacing-widest: 0.1em;

  /* ========== SPACING SYSTEM ========== */

  /* Base spacing unit: 0.25rem (4px) */
  --space-0: 0;
  --space-px: 1px;
  --space-0_5: 0.125rem;  /* 2px */
  --space-1: 0.25rem;     /* 4px */
  --space-1_5: 0.375rem;  /* 6px */
  --space-2: 0.5rem;      /* 8px */
  --space-2_5: 0.625rem;  /* 10px */
  --space-3: 0.75rem;     /* 12px */
  --space-3_5: 0.875rem;  /* 14px */
  --space-4: 1rem;        /* 16px */
  --space-5: 1.25rem;     /* 20px */
  --space-6: 1.5rem;      /* 24px */
  --space-7: 1.75rem;     /* 28px */
  --space-8: 2rem;        /* 32px */
  --space-9: 2.25rem;     /* 36px */
  --space-10: 2.5rem;     /* 40px */
  --space-11: 2.75rem;    /* 44px */
  --space-12: 3rem;       /* 48px */
  --space-14: 3.5rem;     /* 56px */
  --space-16: 4rem;       /* 64px */
  --space-20: 5rem;       /* 80px */
  --space-24: 6rem;       /* 96px */
  --space-28: 7rem;       /* 112px */
  --space-32: 8rem;       /* 128px */
  --space-36: 9rem;       /* 144px */
  --space-40: 10rem;      /* 160px */
  --space-44: 11rem;      /* 176px */
  --space-48: 12rem;      /* 192px */
  --space-52: 13rem;      /* 208px */
  --space-56: 14rem;      /* 224px */
  --space-60: 15rem;      /* 240px */
  --space-64: 16rem;      /* 256px */
  --space-72: 18rem;      /* 288px */
  --space-80: 20rem;      /* 320px */
  --space-96: 24rem;      /* 384px */

  /* ========== SIZING SYSTEM ========== */

  /* Container Sizes */
  --container-sm: 640px;
  --container-md: 768px;
  --container-lg: 1024px;
  --container-xl: 1280px;
  --container-2xl: 1536px;

  /* Content Widths */
  --content-width-prose: 65ch;
  --content-width-narrow: 45rem;
  --content-width-wide: 90rem;
  --content-width-full: 100%;

  /* ========== BORDER RADIUS ========== */

  --radius-none: 0;
  --radius-sm: 0.125rem;   /* 2px */
  --radius-base: 0.25rem;  /* 4px */
  --radius-md: 0.375rem;   /* 6px */
  --radius-lg: 0.5rem;     /* 8px */
  --radius-xl: 0.75rem;    /* 12px */
  --radius-2xl: 1rem;      /* 16px */
  --radius-3xl: 1.5rem;    /* 24px */
  --radius-full: 9999px;

  /* ========== SHADOWS ========== */

  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
  --shadow-base: 0 1px 3px 0 rgba(0, 0, 0, 0.1), 0 1px 2px 0 rgba(0, 0, 0, 0.06);
  --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);
  --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
  --shadow-2xl: 0 25px 50px -12px rgba(0, 0, 0, 0.25);
  --shadow-inner: inset 0 2px 4px 0 rgba(0, 0, 0, 0.06);

  /* Focus Shadows */
  --shadow-focus-primary: 0 0 0 3px rgba(59, 130, 246, 0.15);
  --shadow-focus-secondary: 0 0 0 3px rgba(34, 197, 94, 0.15);
  --shadow-focus-error: 0 0 0 3px rgba(239, 68, 68, 0.15);

  /* ========== BREAKPOINTS ========== */

  --breakpoint-xs: 480px;
  --breakpoint-sm: 640px;
  --breakpoint-md: 768px;
  --breakpoint-lg: 1024px;
  --breakpoint-xl: 1280px;
  --breakpoint-2xl: 1536px;

  /* ========== Z-INDEX SCALE ========== */

  --z-index-hide: -1;
  --z-index-auto: auto;
  --z-index-base: 0;
  --z-index-docked: 10;
  --z-index-dropdown: 1000;
  --z-index-sticky: 1100;
  --z-index-banner: 1200;
  --z-index-overlay: 1300;
  --z-index-modal: 1400;
  --z-index-popover: 1500;
  --z-index-skiplink: 1600;
  --z-index-toast: 1700;
  --z-index-tooltip: 1800;

  /* ========== TRANSITIONS ========== */

  --transition-none: none;
  --transition-all: all 150ms cubic-bezier(0.4, 0, 0.2, 1);
  --transition-default: 150ms cubic-bezier(0.4, 0, 0.2, 1);
  --transition-fast: 100ms cubic-bezier(0.4, 0, 0.2, 1);
  --transition-slow: 300ms cubic-bezier(0.4, 0, 0.2, 1);

  /* Easing Functions */
  --ease-linear: linear;
  --ease-in: cubic-bezier(0.4, 0, 1, 1);
  --ease-out: cubic-bezier(0, 0, 0.2, 1);
  --ease-in-out: cubic-bezier(0.4, 0, 0.2, 1);
  --ease-elastic: cubic-bezier(0.68, -0.55, 0.265, 1.55);

  /* ========== COMPONENT-SPECIFIC TOKENS ========== */

  /* Form Controls */
  --form-control-height: var(--space-12);
  --form-control-padding-x: var(--space-4);
  --form-control-padding-y: var(--space-3);
  --form-control-border-width: 1px;
  --form-control-border-radius: var(--radius-md);

  /* Buttons */
  --button-height-sm: var(--space-8);
  --button-height-md: var(--space-10);
  --button-height-lg: var(--space-12);
  --button-padding-x-sm: var(--space-3);
  --button-padding-x-md: var(--space-4);
  --button-padding-x-lg: var(--space-6);

  /* Cards */
  --card-padding: var(--space-6);
  --card-border-radius: var(--radius-xl);
  --card-border-width: 1px;

  /* Headers */
  --header-height: var(--space-16);
  --navbar-height: var(--space-14);

  /* ========== ACCESSIBILITY TOKENS ========== */

  /* Focus Ring */
  --focus-ring-width: 2px;
  --focus-ring-offset: 2px;
  --focus-ring-color: var(--color-primary-500);

  /* Animation Preferences */
  --animation-duration: 0.2s;
  --animation-easing: ease-in-out;
}

/* ========== REDUCED MOTION ========== */
@media (prefers-reduced-motion: reduce) {
  :root {
    --transition-default: none;
    --transition-fast: none;
    --transition-slow: none;
    --animation-duration: 0.01ms;
  }
}

/* ========== DARK MODE SUPPORT ========== */
@media (prefers-color-scheme: dark) {
  :root {
    /* Override colors for dark mode */
    --color-neutral-0: #0a0a0a;
    --color-neutral-50: #171717;
    --color-neutral-100: #262626;
    --color-neutral-200: #404040;
    --color-neutral-300: #525252;
    --color-neutral-400: #737373;
    --color-neutral-500: #a3a3a3;
    --color-neutral-600: #d4d4d4;
    --color-neutral-700: #e5e5e5;
    --color-neutral-800: #f5f5f5;
    --color-neutral-900: #fafafa;
    --color-neutral-950: #ffffff;
  }
}

/* ========== HIGH CONTRAST MODE ========== */
@media (prefers-contrast: high) {
  :root {
    --shadow-sm: 0 2px 4px 0 rgba(0, 0, 0, 0.3);
    --shadow-base: 0 2px 6px 0 rgba(0, 0, 0, 0.3);
    --shadow-md: 0 8px 12px -2px rgba(0, 0, 0, 0.3);
    --shadow-lg: 0 20px 30px -6px rgba(0, 0, 0, 0.3);
    --shadow-xl: 0 40px 50px -10px rgba(0, 0, 0, 0.3);
  }
}