/**
 * CSS Custom Properties (Variables)
 * Design system foundation for the M&A advisory website
 */

:root {
  /* ============================
     COLOR PALETTE
     ============================ */
  
  /* Primary Colors - Professional Navy Blue */
  --color-primary-50: #e6f0ff;
  --color-primary-100: #b3d1ff;
  --color-primary-200: #80b3ff;
  --color-primary-300: #4d94ff;
  --color-primary-400: #1a75ff;
  --color-primary-500: #003366;  /* Main brand color */
  --color-primary-600: #002952;
  --color-primary-700: #001f3d;
  --color-primary-800: #001429;
  --color-primary-900: #000a14;

  /* Accent Colors - Sophisticated Gold */
  --color-accent-50: #fef9e7;
  --color-accent-100: #fcefc3;
  --color-accent-200: #fae59f;
  --color-accent-300: #f8db7b;
  --color-accent-400: #e6c75b;
  --color-accent-500: #D4AF37;  /* Main accent color */
  --color-accent-600: #b8982f;
  --color-accent-700: #9c8127;
  --color-accent-800: #806a1f;
  --color-accent-900: #645317;

  /* Neutral Grayscale */
  --color-gray-50: #f8f9fa;
  --color-gray-100: #f1f3f5;
  --color-gray-200: #e9ecef;
  --color-gray-300: #dee2e6;
  --color-gray-400: #ced4da;
  --color-gray-500: #adb5bd;
  --color-gray-600: #6c757d;
  --color-gray-700: #495057;
  --color-gray-800: #343a40;
  --color-gray-900: #212529;

  /* Semantic Colors */
  --color-success: #28a745;
  --color-warning: #ffc107;
  --color-error: #dc3545;
  --color-info: #17a2b8;

  /* Text Colors */
  --color-text-primary: var(--color-gray-900);
  --color-text-secondary: var(--color-gray-700);
  --color-text-muted: var(--color-gray-600);
  --color-text-inverse: #ffffff;

  /* Background Colors */
  --color-bg-primary: #ffffff;
  --color-bg-secondary: var(--color-gray-50);
  --color-bg-tertiary: var(--color-gray-100);
  --color-bg-dark: var(--color-primary-500);

  /* Border Colors */
  --color-border-light: var(--color-gray-200);
  --color-border-medium: var(--color-gray-300);
  --color-border-dark: var(--color-gray-400);

  /* ============================
     TYPOGRAPHY
     ============================ */
  
  /* Font Families */
  --font-primary: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
  --font-secondary: 'Montserrat', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --font-mono: 'Courier New', Courier, monospace;

  /* Font Sizes - Responsive Scale */
  --font-size-xs: 0.75rem;      /* 12px */
  --font-size-sm: 0.875rem;     /* 14px */
  --font-size-base: 1rem;       /* 16px */
  --font-size-lg: 1.125rem;     /* 18px */
  --font-size-xl: 1.25rem;      /* 20px */
  --font-size-2xl: 1.5rem;      /* 24px */
  --font-size-3xl: 1.875rem;    /* 30px */
  --font-size-4xl: 2.25rem;     /* 36px */
  --font-size-5xl: 3rem;        /* 48px */
  --font-size-6xl: 3.75rem;     /* 60px */
  --font-size-7xl: 4.5rem;      /* 72px */

  /* Font Weights */
  --font-weight-light: 300;
  --font-weight-normal: 400;
  --font-weight-medium: 500;
  --font-weight-semibold: 600;
  --font-weight-bold: 700;
  --font-weight-extrabold: 800;

  /* Line Heights */
  --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-tight: -0.025em;
  --letter-spacing-normal: 0;
  --letter-spacing-wide: 0.025em;
  --letter-spacing-wider: 0.05em;
  --letter-spacing-widest: 0.1em;

  /* ============================
     SPACING SYSTEM
     ============================ */
  
  /* Base unit: 4px (0.25rem) */
  --spacing-xs: 0.5rem;      /* 8px */
  --spacing-sm: 0.75rem;     /* 12px */
  --spacing-md: 1rem;        /* 16px */
  --spacing-lg: 1.5rem;      /* 24px */
  --spacing-xl: 2rem;        /* 32px */
  --spacing-2xl: 2.5rem;     /* 40px */
  --spacing-3xl: 3rem;       /* 48px */
  --spacing-4xl: 4rem;       /* 64px */
  --spacing-5xl: 5rem;       /* 80px */

  /* Section Spacing */
  --section-padding-y: 5rem;
  --section-padding-x: 1.5rem;

  /* Container Max Width */
  --container-max-width: 1280px;
  --container-narrow: 960px;
  --container-wide: 1536px;

  /* ============================
     BORDER & RADIUS
     ============================ */
  
  --border-width-thin: 1px;
  --border-width-medium: 2px;
  --border-width-thick: 4px;

  --border-radius-sm: 0.25rem;   /* 4px */
  --border-radius-md: 0.5rem;    /* 8px */
  --border-radius-lg: 0.75rem;   /* 12px */
  --border-radius-xl: 1rem;      /* 16px */
  --border-radius-full: 9999px;

  /* ============================
     SHADOWS
     ============================ */
  
  --shadow-xs: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
  --shadow-sm: 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);

  /* ============================
     TRANSITIONS
     ============================ */
  
  --transition-fast: 150ms ease-in-out;
  --transition-base: 250ms ease-in-out;
  --transition-slow: 350ms ease-in-out;

  --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);

  /* ============================
     Z-INDEX LAYERS
     ============================ */
  
  --z-index-dropdown: 1000;
  --z-index-sticky: 1020;
  --z-index-fixed: 1030;
  --z-index-modal-backdrop: 1040;
  --z-index-modal: 1050;
  --z-index-popover: 1060;
  --z-index-tooltip: 1070;

  /* ============================
     BREAKPOINTS (for reference)
     ============================ */
  
  /* 
  These are defined in responsive.css as media queries:
  - sm: 640px
  - md: 768px
  - lg: 1024px
  - xl: 1280px
  - 2xl: 1536px
  */
}

/* Dark mode support (optional - implement if needed) */
@media (prefers-color-scheme: dark) {
  /* Uncomment and customize when implementing dark mode */
  /*
  :root {
    --color-bg-primary: var(--color-gray-900);
    --color-bg-secondary: var(--color-gray-800);
    --color-text-primary: var(--color-gray-50);
    --color-text-secondary: var(--color-gray-300);
  }
  */
}