/**
 * Modern Design System - CSS Variables Only
 * Simplified for Bootstrap 4 integration
 * White background + Blue accent theme
 */

/* ========================================
   CSS Variables - Design Tokens
   ======================================== */

:root {
  /* === Primary Blue Theme === */
  --primary: #0066FF;
  --primary-hover: #0052CC;
  --primary-light: #E6F0FF;
  --primary-dark: #003D99;

  /* === Color Palette === */
  --success: #00C853;
  --warning: #FFB300;
  --danger: #F44336;
  --info: #00B0FF;

  /* === Neutral Grays === */
  --gray-50: #F9FAFB;
  --gray-100: #F3F4F6;
  --gray-200: #E5E7EB;
  --gray-300: #D1D5DB;
  --gray-400: #9CA3AF;
  --gray-500: #6B7280;
  --gray-600: #4B5563;
  --gray-700: #374151;
  --gray-800: #1F2937;
  --gray-900: #111827;

  /* === Background === */
  --bg-primary: #FFFFFF;
  --bg-secondary: #F9FAFB;
  --bg-hover: #F3F4F6;

  /* === Text Colors === */
  --text-primary: #111827;
  --text-secondary: #6B7280;
  --text-muted: #9CA3AF;
  --text-white: #FFFFFF;

  /* === Borders === */
  --border-light: #E5E7EB;
  --border-medium: #D1D5DB;
  --border-dark: #9CA3AF;

  /* === Border Radius === */
  --radius-sm: 4px;
  --radius-md: 6px;
  --radius-lg: 8px;
  --radius-xl: 12px;
  --radius-full: 9999px;

  /* === Shadows === */
  --shadow-xs: 0 1px 2px rgba(0, 0, 0, 0.05);
  --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.1), 0 1px 2px rgba(0, 0, 0, 0.06);
  --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.07), 0 2px 4px rgba(0, 0, 0, 0.06);
  --shadow-lg: 0 10px 15px rgba(0, 0, 0, 0.1), 0 4px 6px rgba(0, 0, 0, 0.05);
  --shadow-xl: 0 20px 25px rgba(0, 0, 0, 0.1), 0 10px 10px rgba(0, 0, 0, 0.04);

  /* === Transitions === */
  --transition-fast: 0.15s ease;
  --transition-base: 0.2s ease-in-out;
  --transition-slow: 0.25s ease;

  /* === Layout === */
  --navbar-height: 64px;
  --sidebar-width: 240px;

  /* === Typography === */
  --font-system: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
}

/* ========================================
   Bootstrap 4 Theme Overrides
   ======================================== */

/* Body */
body {
  font-family: var(--font-system);
  color: var(--text-primary);
  background-color: var(--bg-secondary);
}

/* Links */
a {
  color: var(--primary);
  transition: color var(--transition-fast);
}

a:hover {
  color: var(--primary-hover);
}

/* ========================================
   Bootstrap 4 Component Customizations
   ======================================== */

/* Primary Button */
.btn-primary {
  background-color: var(--primary);
  border-color: var(--primary);
}

.btn-primary:hover,
.btn-primary:focus,
.btn-primary:active {
  background-color: var(--primary-hover);
  border-color: var(--primary-hover);
}

/* Badges */
.badge-primary {
  background-color: var(--primary);
}

/* Active Navigation Link */
.nav-link.active {
  color: var(--primary) !important;
  background-color: var(--primary-light);
  border-radius: var(--radius-lg);
}

/* Custom Checkbox */
.custom-control-input:checked ~ .custom-control-label::before {
  background-color: var(--primary);
  border-color: var(--primary);
}

/* Alert Primary */
.alert-primary {
  background-color: var(--primary-light);
  border-color: var(--primary-light);
  color: var(--primary-dark);
}

/* ========================================
   Utility Classes
   ======================================== */

/* Font Weight */
.font-weight-medium {
  font-weight: 500;
}

/* Shadow Utilities */
.shadow-xs { box-shadow: var(--shadow-xs); }
.shadow-sm { box-shadow: var(--shadow-sm); }
.shadow-md { box-shadow: var(--shadow-md); }
.shadow-lg { box-shadow: var(--shadow-lg); }
.shadow-xl { box-shadow: var(--shadow-xl); }

/* Responsive Mobile */
@media (max-width: 767px) {
  :root {
    --navbar-height: 56px;
  }
}

@media (min-width: 1400px) {
  :root {
    --sidebar-width: 260px;
  }
}