/*
  DESIGN SYSTEM - Military Academic Theme

  Complete CSS variable system and component classes for consistent styling
  across the entire application.

  To use: Import this file and apply the classes/variables as needed.
*/

/* ============================================
   CSS VARIABLES - The Foundation
   ============================================ */

:root {
  /* PRIMARY PALETTE - Military Green */
  --primary: #556B2F;        /* Army green - main brand color */
  --primary-dark: #3d4d22;   /* Darker green for hovers */
  --primary-light: #8b9f6f;  /* Lighter green for accents */

  /* ACCENT COLORS - Semantic Categorization */
  --accent-green: #556B2F;        /* Concepts - matches primary */
  --accent-green-light: #e8ebe0;  /* Pastel version */

  --accent-blue: #2d5466;         /* Sources - slate blue */
  --accent-blue-dark: #234552;    /* Darker blue for hovers */
  --accent-blue-light: #e3eaed;   /* Pastel version */

  --accent-gold: #a67c2e;         /* People - brass/gold */
  --accent-gold-light: #f5efe0;   /* Pastel version */

  --accent-purple: #674675;       /* Tags - muted plum */
  --accent-purple-light: #ebe5ed; /* Pastel version */

  --accent-teal: #639CA1;         /* Notes - teal */
  --accent-teal-light: #e8f2f3;   /* Pastel version */

  /* SEMANTIC COLORS - Feedback & States */
  --success: var(--primary);      /* Green for success messages */
  --warning: var(--accent-gold);  /* Brass for warnings */
  --error: #8b2d2d;               /* Burgundy for errors (not fire truck red) */

  /* NEUTRAL PALETTE - Grays */
  --neutral-100: #e8e6e1;    /* Subtle divisions, hover states */
  --neutral-200: #d1cec6;    /* Borders, dividers */
  --neutral-300: #b8b5ad;    /* Disabled states */
  --neutral-400: #9a968e;    /* Placeholder text */
  --neutral-500: #6e6b65;    /* Secondary text */
  --neutral-600: #4a4843;    /* Body text */
  --neutral-700: #363430;    /* Headings */
  --neutral-800: #252421;    /* Dark backgrounds */
  --neutral-900: #1a1917;    /* Maximum contrast */

  /* BACKGROUNDS */
  --background: #ffffff;       /* Clean white - main content area */
  --sidebar-bg: #f5f5f5;       /* Light greige - sidebar */
  --card-header: #ffffff;      /* White - card headers */
  --card-footer: #f5f5f5;      /* Light gray - card footers */

  /* TYPOGRAPHY */
  --font-body: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
  --font-display: 'Merriweather', Georgia, serif; /* For headings, labels, buttons */

  /* FONT SIZES */
  --text-xs: 0.75rem;        /* 12px - tiny labels */
  --text-sm: 0.875rem;       /* 14px - body text */
  --text-base: 0.9375rem;    /* 15px - base size */
  --text-lg: 1.125rem;       /* 18px - subheadings */
  --text-xl: 1.25rem;        /* 20px - headings */
  --text-2xl: 1.5rem;        /* 24px - page titles */
  --text-3xl: 1.875rem;      /* 30px - hero text */

  /* SPACING SCALE - 4px base unit */
  --space-1: 0.25rem;   /* 4px */
  --space-2: 0.5rem;    /* 8px */
  --space-3: 0.75rem;   /* 12px */
  --space-4: 1rem;      /* 16px */
  --space-6: 1.5rem;    /* 24px */
  --space-8: 2rem;      /* 32px */

  /* BORDER RADIUS */
  --radius-sm: 2px;     /* Small elements (icon buttons, small tags) */
  --radius: 4px;        /* Standard (buttons, inputs, cards) */
  --radius-full: 9999px; /* Pills (badges, toggles) */

  /* SHADOWS - Depth & Layering */
  --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
  --shadow: 0 1px 3px 0 rgb(0 0 0 / 0.1), 0 1px 2px -1px rgb(0 0 0 / 0.1);
  --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);
  --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1), 0 4px 6px -4px rgb(0 0 0 / 0.1);
  --shadow-card: 0 2px 8px rgba(0, 0, 0, 0.12), 0 1px 3px rgba(0, 0, 0, 0.08);
  --shadow-card-hover: 0 8px 20px rgba(0, 0, 0, 0.15), 0 3px 6px rgba(0, 0, 0, 0.10);
  --shadow-sidebar: inset -8px 0 16px -8px rgba(0, 0, 0, 0.25);
  --shadow-nav: 0 4px 12px rgba(0, 0, 0, 0.4);

  /* TRANSITIONS */
  --transition-fast: 0.15s ease;
  --transition-base: 0.2s ease;
}

/* ============================================
   BUTTON COMPONENTS
   ============================================ */

/* Primary Button - Main actions */
.btn-primary {
  background: var(--primary);
  color: white;
  border: none;
  padding: var(--space-2) var(--space-4);
  border-radius: var(--radius);
  font-family: var(--font-display);
  font-size: var(--text-sm);
  font-weight: 600;
  cursor: pointer;
  transition: all var(--transition-fast);
}

.btn-primary:hover {
  background: var(--primary-dark);
  transform: translateY(-1px);
  box-shadow: var(--shadow-md);
}

.btn-primary:disabled {
  opacity: 0.5;
  cursor: not-allowed;
  transform: none;
}

/* Secondary Button - Outline style */
.btn-secondary {
  background: transparent;
  color: var(--neutral-700);
  border: 1px solid var(--neutral-300);
  padding: var(--space-2) var(--space-4);
  border-radius: var(--radius);
  font-family: var(--font-display);
  font-size: var(--text-sm);
  font-weight: 500;
  cursor: pointer;
  transition: all var(--transition-fast);
}

.btn-secondary:hover {
  background: var(--neutral-100);
  border-color: var(--neutral-400);
}

/* Primary Outline Button */
.btn-outline-primary {
  background: transparent;
  color: var(--primary);
  border: 1px solid var(--primary);
  padding: var(--space-2) var(--space-4);
  border-radius: var(--radius);
  font-family: var(--font-display);
  font-size: var(--text-sm);
  font-weight: 600;
  cursor: pointer;
  transition: all var(--transition-fast);
}

.btn-outline-primary:hover {
  background: color-mix(in srgb, var(--primary) 10%, transparent);
}

/* Destructive Button */
.btn-destructive {
  background: var(--error);
  color: white;
  border: none;
  padding: var(--space-2) var(--space-4);
  border-radius: var(--radius);
  font-family: var(--font-display);
  font-size: var(--text-sm);
  font-weight: 600;
  cursor: pointer;
  transition: all var(--transition-fast);
}

.btn-destructive:hover {
  background: color-mix(in srgb, var(--error) 80%, black);
  transform: translateY(-1px);
  box-shadow: var(--shadow-md);
}

/* Destructive Outline */
.btn-outline-destructive {
  background: transparent;
  color: var(--error);
  border: 1px solid var(--error);
  padding: var(--space-2) var(--space-4);
  border-radius: var(--radius);
  font-family: var(--font-display);
  font-size: var(--text-sm);
  font-weight: 600;
  cursor: pointer;
  transition: all var(--transition-fast);
}

.btn-outline-destructive:hover {
  background: color-mix(in srgb, var(--error) 10%, transparent);
}

/* Colored Variant Buttons - For semantic actions */
.btn-source {
  background: var(--accent-blue);
  color: white;
  border: none;
  padding: var(--space-2) var(--space-4);
  border-radius: var(--radius);
  font-family: var(--font-display);
  font-size: var(--text-sm);
  font-weight: 600;
  cursor: pointer;
  transition: all var(--transition-fast);
}

.btn-person {
  background: var(--accent-gold);
  color: white;
  border: none;
  padding: var(--space-2) var(--space-4);
  border-radius: var(--radius);
  font-family: var(--font-display);
  font-size: var(--text-sm);
  font-weight: 600;
  cursor: pointer;
  transition: all var(--transition-fast);
}

/* Icon Button */
.icon-btn {
  background: none;
  border: none;
  color: var(--neutral-500);
  cursor: pointer;
  padding: var(--space-1);
  border-radius: var(--radius-sm);
  transition: all var(--transition-fast);
  display: flex;
  align-items: center;
  justify-content: center;
  width: 24px;
  height: 24px;
}

.icon-btn:hover {
  background: var(--neutral-200);
  color: var(--neutral-700);
}

.icon-btn.pinned {
  color: var(--primary);
}

/* ============================================
   NAVIGATION COMPONENTS
   ============================================ */

/* Navigation Link - Desktop */
.nav-link {
  font-family: var(--font-display);
  color: rgba(255, 255, 255, 0.85);
  text-decoration: none;
  font-size: var(--text-sm);
  font-weight: 500;
  padding: var(--space-2) var(--space-3);
  border-radius: var(--radius);
  transition: all var(--transition-fast);
  background: transparent;
}

.nav-link:hover {
  color: white;
  background: rgba(255, 255, 255, 0.15);
}

.nav-link.active {
  color: white;
  background: rgba(255, 255, 255, 0.2);
}

/* Mobile Navigation Link */
.mobile-nav-link {
  display: block;
  padding: 0.75rem 1rem;
  font-size: var(--text-base);
  color: white;
  text-decoration: none;
  border-radius: var(--radius);
  background: transparent;
  font-weight: 400;
  margin-bottom: 0.25rem;
  transition: background var(--transition-fast);
}

.mobile-nav-link:hover {
  background: rgba(255, 255, 255, 0.15);
}

.mobile-nav-link.active {
  background: rgba(255, 255, 255, 0.2);
  font-weight: 500;
}

/* ============================================
   FORM COMPONENTS
   ============================================ */

/* Form Label */
.form-label {
  display: block;
  font-family: var(--font-display);
  font-size: var(--text-sm);
  font-weight: 500;
  margin-bottom: 0.25rem;
  color: var(--neutral-700);
}

.form-label.required::after {
  content: " *";
  color: var(--error);
}

/* Teal variant for notes modal */
.form-label.required.teal::after {
  color: var(--accent-teal);
}

/* Helper Text */
.form-helper {
  font-family: var(--font-body);
  font-size: var(--text-xs);
  color: var(--neutral-500);
  margin-bottom: 0.25rem;
}

/* Error Message */
.form-error {
  font-family: var(--font-body);
  font-size: var(--text-xs);
  color: var(--error);
  margin-top: 0.25rem;
}

/* Text Input */
.form-input {
  width: 100%;
  padding: var(--space-3);
  border: 1px solid var(--neutral-300);
  border-radius: var(--radius);
  font-family: var(--font-body);
  font-size: var(--text-sm);
  transition: all var(--transition-fast);
}

.form-input:focus {
  outline: none;
  border: 2px solid var(--primary);
  padding: calc(var(--space-3) - 1px); /* Compensate for thicker border */
  box-shadow: 0 0 0 3px color-mix(in srgb, var(--primary) 10%, transparent);
}

.form-input.error {
  border: 2px solid var(--error);
  padding: calc(var(--space-3) - 1px);
}

.form-input::placeholder {
  color: var(--neutral-400);
}

/* Select Dropdown */
.form-select {
  width: 100%;
  padding: var(--space-3);
  border: 1px solid var(--neutral-300);
  border-radius: var(--radius);
  font-family: var(--font-body);
  font-size: var(--text-sm);
  background: white;
  cursor: pointer;
  transition: all var(--transition-fast);
}

.form-select:focus {
  outline: none;
  border: 2px solid var(--primary);
  padding: calc(var(--space-3) - 1px);
  box-shadow: 0 0 0 3px color-mix(in srgb, var(--primary) 10%, transparent);
}

/* Textarea */
.form-textarea {
  width: 100%;
  padding: var(--space-3);
  border: 1px solid var(--neutral-300);
  border-radius: var(--radius);
  font-family: var(--font-body);
  font-size: var(--text-sm);
  resize: vertical;
  transition: all var(--transition-fast);
}

.form-textarea:focus {
  outline: none;
  border: 2px solid var(--primary);
  padding: calc(var(--space-3) - 1px);
  box-shadow: 0 0 0 3px color-mix(in srgb, var(--primary) 10%, transparent);
}

/* Checkbox & Radio Styling */
input[type="checkbox"],
input[type="radio"] {
  width: 16px;
  height: 16px;
  cursor: pointer;
  accent-color: var(--primary);
  flex-shrink: 0;
}

/* Checkbox/Radio Item Wrapper */
.form-check-item {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  cursor: pointer;
  padding: var(--space-2);
  border-radius: var(--radius);
  transition: background var(--transition-fast);
}

.form-check-item:hover {
  background: var(--neutral-100);
}

.form-check-item input:disabled {
  cursor: not-allowed;
  opacity: 0.5;
}

.form-check-item span {
  font-size: var(--text-sm);
  font-family: var(--font-body);
}

/* ============================================
   TOGGLE SWITCH
   ============================================ */

.toggle-switch {
  position: relative;
  width: 44px;
  height: 24px;
  background: var(--neutral-300);
  border-radius: var(--radius-full);
  transition: background var(--transition-base);
  cursor: pointer;
}

.toggle-switch.active {
  background: var(--primary);
}

.toggle-switch .toggle-slider {
  position: absolute;
  top: 2px;
  left: 2px;
  width: 20px;
  height: 20px;
  background: white;
  border-radius: 50%;
  transition: transform var(--transition-base);
}

.toggle-switch.active .toggle-slider {
  transform: translateX(20px);
}

.toggle-switch.disabled {
  opacity: 0.5;
  cursor: not-allowed;
}

/* ============================================
   BADGES & TAGS
   ============================================ */

/* Tag - Pastel version for cards */
.tag {
  padding: 0.25rem 0.5rem;
  border-radius: var(--radius-sm);
  font-family: var(--font-body);
  font-size: var(--text-xs);
  font-weight: 500;
  background: var(--neutral-100);
  color: var(--neutral-700);
  text-decoration: none;
  transition: all var(--transition-fast);
  display: inline-block;
}

.tag:hover {
  background: var(--neutral-200);
}

/* Semantic Tag Colors - Pastel */
.tag.concept {
  background: var(--accent-green-light);
  color: var(--accent-green);
}

.tag.source {
  background: var(--accent-blue-light);
  color: var(--accent-blue);
}

.tag.person {
  background: var(--accent-gold-light);
  color: var(--accent-gold);
}

.tag.tag-purple {
  background: var(--accent-purple-light);
  color: var(--accent-purple);
}

/* Filter Badge - Bold pill version */
.filter-badge {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  padding: 0.375rem 0.75rem;
  color: white;
  border-radius: var(--radius-full);
  font-family: var(--font-body);
  font-size: var(--text-xs);
  font-weight: 500;
}

/* Color-coded filter badges */
.filter-badge.concept { background: var(--accent-green); }
.filter-badge.source { background: var(--accent-blue); }
.filter-badge.person { background: var(--accent-gold); }
.filter-badge.tag { background: var(--accent-purple); }

.filter-badge button {
  background: none;
  border: none;
  color: white;
  cursor: pointer;
  padding: 0;
  font-size: var(--text-sm);
}

/* ============================================
   ALERTS & MESSAGES
   ============================================ */

.alert {
  padding: var(--space-3) var(--space-4);
  border-left: 4px solid;
  border-radius: var(--radius);
  font-size: var(--text-sm);
  font-family: var(--font-body);
}

.alert-title {
  font-family: var(--font-display);
  font-weight: 600;
  margin-right: 0.25rem;
}

.alert-success {
  background: color-mix(in srgb, var(--success) 10%, transparent);
  border-color: var(--success);
}

.alert-success .alert-title {
  color: var(--success);
}

.alert-warning {
  background: color-mix(in srgb, var(--warning) 10%, transparent);
  border-color: var(--warning);
}

.alert-warning .alert-title {
  color: var(--warning);
}

.alert-error {
  background: color-mix(in srgb, var(--error) 10%, transparent);
  border-color: var(--error);
}

.alert-error .alert-title {
  color: var(--error);
}

.alert-info {
  background: color-mix(in srgb, var(--primary) 10%, transparent);
  border-color: var(--primary);
}

.alert-info .alert-title {
  color: var(--primary);
}

/* ============================================
   CARDS
   ============================================ */

.card {
  background: white;
  border: 1px solid var(--neutral-200);
  border-radius: var(--radius);
  overflow: hidden;
  display: flex;
  flex-direction: column;
  transition: all var(--transition-base);
  box-shadow: var(--shadow-card);
}

.card:hover {
  box-shadow: var(--shadow-card-hover);
  transform: translateY(-2px);
}

.card-header {
  background: var(--card-header);
  padding: var(--space-3) var(--space-4);
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.card-title {
  font-family: var(--font-body);
  font-size: var(--text-sm);
  font-weight: 600;
  color: var(--neutral-900);
  flex: 1;
}

.card-body {
  padding: var(--space-4);
  flex: 1;
}

.card-footer {
  padding: var(--space-2) var(--space-4);
  background: var(--card-footer);
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: var(--text-xs);
  color: var(--neutral-500);
  margin-top: auto;
}

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

h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-display);
  font-weight: 700;
  line-height: 1.2;
  color: var(--neutral-700);
}

.text-display {
  font-family: var(--font-display);
}

.text-body {
  font-family: var(--font-body);
}

/* ============================================
   ICON SYSTEM
   ============================================ */

.icon {
  color: var(--primary);
}

.icon.white {
  color: white;
}

/* ============================================
   LOADING STATES
   ============================================ */

.loading-spinner {
  animation: spin 1s linear infinite;
}

@keyframes spin {
  from { transform: rotate(0deg); }
  to { transform: rotate(360deg); }
}

.progress-bar {
  width: 200px;
  height: 4px;
  background: var(--neutral-200);
  border-radius: var(--radius-full);
  overflow: hidden;
}

.progress-bar-fill {
  height: 100%;
  background: var(--primary);
  border-radius: var(--radius-full);
  transition: width var(--transition-base);
}

/* ============================================
   RESPONSIVE UTILITIES
   ============================================ */

/* Sidebar toggle visible on all screen sizes */

/* ============================================
   SIDEBAR & NAVIGATION COMPONENTS
   ============================================ */

.sidebar {
  background: var(--sidebar-bg);
  box-shadow: var(--shadow-sidebar);
}

.sidebar-section {
  margin-bottom: var(--space-6);
}

.sidebar-section-title {
  font-family: var(--font-body);
  font-size: var(--text-xs);
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--neutral-500);
  margin-bottom: var(--space-3);
}

/* ============================================
   UTILITY CLASSES
   ============================================ */

/* Shadows */
.shadow-sm { box-shadow: var(--shadow-sm); }
.shadow { box-shadow: var(--shadow); }
.shadow-md { box-shadow: var(--shadow-md); }
.shadow-lg { box-shadow: var(--shadow-lg); }

/* Spacing */
.p-0 { padding: 0; }
.p-1 { padding: var(--space-1); }
.p-2 { padding: var(--space-2); }
.p-3 { padding: var(--space-3); }
.p-4 { padding: var(--space-4); }
.p-6 { padding: var(--space-6); }
.p-8 { padding: var(--space-8); }

.m-0 { margin: 0; }
.m-1 { margin: var(--space-1); }
.m-2 { margin: var(--space-2); }
.m-3 { margin: var(--space-3); }
.m-4 { margin: var(--space-4); }
.m-6 { margin: var(--space-6); }
.m-8 { margin: var(--space-8); }

/* Border Radius */
.rounded-sm { border-radius: var(--radius-sm); }
.rounded { border-radius: var(--radius); }
.rounded-full { border-radius: var(--radius-full); }