/**
 * GLOBAL DESIGN SYSTEM - global.css
 * Premium Light Theme | Minimal, High-End Corporate Design
 * Target: Fresh Graduates (early to mid-20s)
 * 
 * Design Principles:
 * - Strict light theme with minimal aesthetic
 * - Clean Bento-box grids maximizing whitespace
 * - Subtle borders over heavy shadows
 * - Typography hierarchy via font-weight, not size
 * - Bootstrap Icons only at uniform 20px
 */

/* ============================================================
   1. ROOT VARIABLES & DESIGN TOKENS
   ============================================================ */

:root {
  /* Primary Accent - Modern, Professional Blue */
  --color-primary: #2563eb;
  --color-primary-light: #3b82f6;
  --color-primary-hover: #1d4ed8;
  --color-primary-subtle: #eff6ff;

  /* Semantic Colors */
  --color-success: #059669;
  --color-success-light: #ecfdf5;
  --color-warning: #d97706;
  --color-warning-light: #fffbeb;
  --color-danger: #dc2626;
  --color-danger-light: #fef2f2;
  --color-info: #0891b2;
  --color-info-light: #ecf0ff;

  /* Neutral Palette */
  --color-text-primary: #1f2937;
  --color-text-secondary: #6b7280;
  --color-text-muted: #9ca3af;
  --color-text-light: #d1d5db;

  /* Backgrounds */
  --color-bg-app: #f9fafb;
  --color-bg-surface: #ffffff;
  --color-bg-hover: #f3f4f6;
  --color-bg-active: #eff6ff;

  /* Borders & Dividers */
  --color-border: #e5e7eb;
  --color-border-light: #f3f4f6;
  --color-border-strong: #d1d5db;

  /* Spacing System (8px base) */
  --spacing-xs: 0.25rem;
  --spacing-sm: 0.5rem;
  --spacing-md: 1rem;
  --spacing-lg: 1.5rem;
  --spacing-xl: 2rem;
  --spacing-2xl: 2.5rem;
  --spacing-3xl: 3rem;

  /* Border Radius */
  --radius-sm: 0.375rem;
  --radius-md: 0.5rem;
  --radius-lg: 0.75rem;
  --radius-xl: 1rem;
  --radius-full: 9999px;

  /* Shadows - Minimal, Subtle */
  --shadow-none: none;
  --shadow-xs: 0 1px 2px rgba(0, 0, 0, 0.05);
  --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.08);
  --shadow-md: 0 2px 4px rgba(0, 0, 0, 0.08);
  --shadow-lg: 0 4px 6px rgba(0, 0, 0, 0.1);
  --shadow-xl: 0 10px 15px rgba(0, 0, 0, 0.1);

  /* Typography */
  --font-family-base: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto', 'Oxygen', 'Ubuntu', 'Cantarell', sans-serif;
  --font-family-mono: 'Menlo', 'Monaco', 'Courier New', monospace;

  --font-size-xs: 0.75rem;
  --font-size-sm: 0.875rem;
  --font-size-base: 1rem;
  --font-size-lg: 1.125rem;
  --font-size-xl: 1.25rem;
  --font-size-2xl: 1.5rem;
  --font-size-3xl: 1.875rem;

  --font-weight-light: 300;
  --font-weight-normal: 400;
  --font-weight-medium: 500;
  --font-weight-semibold: 600;
  --font-weight-bold: 700;

  --line-height-tight: 1.25;
  --line-height-normal: 1.5;
  --line-height-relaxed: 1.75;

  /* Transitions & Animation */
  --transition-fast: 150ms cubic-bezier(0.4, 0, 0.2, 1);
  --transition-normal: 300ms cubic-bezier(0.4, 0, 0.2, 1);
  --transition-slow: 500ms cubic-bezier(0.4, 0, 0.2, 1);

  /* Z-Index Scale */
  --z-dropdown: 1000;
  --z-sticky: 1020;
  --z-fixed: 1030;
  --z-modal-backdrop: 1040;
  --z-modal: 1050;
  --z-popover: 1060;
  --z-tooltip: 1070;
}

/* ============================================================
   2. RESET & BASE STYLES
   ============================================================ */

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: var(--font-family-base);
  font-size: var(--font-size-base);
  font-weight: var(--font-weight-normal);
  line-height: var(--line-height-normal);
  color: var(--color-text-primary);
  background-color: var(--color-bg-app);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

/* ============================================================
   3. TYPOGRAPHY
   ============================================================ */

h1, h2, h3, h4, h5, h6 {
  margin: 0;
  font-weight: var(--font-weight-bold);
  line-height: var(--line-height-tight);
}

h1 {
  font-size: var(--font-size-3xl);
}

h2 {
  font-size: var(--font-size-2xl);
}

h3 {
  font-size: var(--font-size-xl);
}

h4 {
  font-size: var(--font-size-lg);
}

h5, h6 {
  font-size: var(--font-size-base);
}

p {
  margin-bottom: var(--spacing-md);
}

p:last-child {
  margin-bottom: 0;
}

a {
  color: var(--color-primary);
  text-decoration: none;
  transition: color var(--transition-fast);
}

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

strong, .font-weight-bold {
  font-weight: var(--font-weight-bold);
}

.text-muted {
  color: var(--color-text-secondary);
}

.text-light {
  color: var(--color-text-muted);
}

/* ============================================================
   4. CARD & CONTAINER COMPONENTS
   ============================================================ */

.card {
  background-color: var(--color-bg-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-xs);
  transition: all var(--transition-normal);
  overflow: hidden;
}

.card:hover {
  box-shadow: var(--shadow-md);
  border-color: var(--color-primary-light);
}

.card-header {
  padding: var(--spacing-lg);
  background-color: var(--color-bg-surface);
  border-bottom: 1px solid var(--color-border);
  font-weight: var(--font-weight-semibold);
  font-size: var(--font-size-lg);
}

.card-body {
  padding: var(--spacing-lg);
}

.card-footer {
  padding: var(--spacing-lg);
  background-color: var(--color-bg-hover);
  border-top: 1px solid var(--color-border);
}

/* Bento Grid Containers */
.bento-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: var(--spacing-xl);
  margin-bottom: var(--spacing-2xl);
}

.bento-grid-2 {
  grid-template-columns: repeat(2, 1fr);
}

.bento-grid-3 {
  grid-template-columns: repeat(3, 1fr);
}

.bento-grid-4 {
  grid-template-columns: repeat(4, 1fr);
}

@media (max-width: 1024px) {
  .bento-grid-3 {
    grid-template-columns: repeat(2, 1fr);
  }

  .bento-grid-4 {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 640px) {
  .bento-grid,
  .bento-grid-2,
  .bento-grid-3,
  .bento-grid-4 {
    grid-template-columns: 1fr;
  }
}

/* ============================================================
   5. BUTTON COMPONENTS
   ============================================================ */

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font-size: var(--font-size-sm);
  font-weight: var(--font-weight-medium);
  padding: var(--spacing-sm) var(--spacing-lg);
  border: 1px solid transparent;
  border-radius: var(--radius-md);
  cursor: pointer;
  transition: all var(--transition-fast);
  text-decoration: none;
  white-space: nowrap;
  user-select: none;
}

.btn:focus {
  outline: none;
}

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

.btn-primary:hover {
  background-color: var(--color-primary-hover);
  border-color: var(--color-primary-hover);
  box-shadow: var(--shadow-md);
}

.btn-primary:active {
  transform: scale(0.98);
}

.btn-primary:disabled {
  background-color: var(--color-text-light);
  border-color: var(--color-text-light);
  cursor: not-allowed;
  opacity: 0.6;
}

/* Secondary Button */
.btn-secondary {
  background-color: var(--color-bg-hover);
  color: var(--color-text-primary);
  border-color: var(--color-border);
}

.btn-secondary:hover {
  background-color: var(--color-border);
  border-color: var(--color-border-strong);
}

/* Success Button */
.btn-success {
  background-color: var(--color-success);
  color: #ffffff;
  border-color: var(--color-success);
}

.btn-success:hover {
  background-color: #047857;
  border-color: #047857;
}

/* Danger Button */
.btn-danger {
  background-color: var(--color-danger);
  color: #ffffff;
  border-color: var(--color-danger);
}

.btn-danger:hover {
  background-color: #b91c1c;
  border-color: #b91c1c;
}

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

.btn-ghost:hover {
  background-color: var(--color-primary-subtle);
  border-color: var(--color-primary);
}

/* Small Button */
.btn-sm {
  padding: var(--spacing-xs) var(--spacing-md);
  font-size: var(--font-size-xs);
}

/* Large Button */
.btn-lg {
  padding: var(--spacing-md) var(--spacing-xl);
  font-size: var(--font-size-base);
}

/* Button Group */
.btn-group {
  display: inline-flex;
  gap: var(--spacing-sm);
}

/* Icon Button */
.btn-icon {
  width: 2.5rem;
  height: 2.5rem;
  padding: 0;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-md);
}

.btn i,
.btn [class^="bi-"] {
  font-size: 20px;
  margin-right: var(--spacing-sm);
}

.btn i:last-child,
.btn [class^="bi-"]:last-child {
  margin-right: 0;
}

/* ============================================================
   6. FORM ELEMENTS
   ============================================================ */

.form-group {
  margin-bottom: var(--spacing-lg);
}

.form-group:last-child {
  margin-bottom: 0;
}

.form-label {
  display: block;
  font-size: var(--font-size-sm);
  font-weight: var(--font-weight-medium);
  color: var(--color-text-primary);
  margin-bottom: var(--spacing-sm);
}

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

.form-control {
  display: block;
  width: 100%;
  padding: var(--spacing-sm) var(--spacing-md);
  font-size: var(--font-size-sm);
  font-family: inherit;
  background-color: var(--color-bg-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  transition: all var(--transition-fast);
  color: var(--color-text-primary);
}

.form-control:focus {
  outline: none;
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px var(--color-primary-subtle);
}

.form-control:disabled {
  background-color: var(--color-bg-hover);
  color: var(--color-text-muted);
  cursor: not-allowed;
}

.form-control::placeholder {
  color: var(--color-text-muted);
}

select.form-control {
  cursor: pointer;
}

textarea.form-control {
  resize: vertical;
  min-height: 120px;
}

/* Form Help Text */
.form-text {
  display: block;
  font-size: var(--font-size-xs);
  color: var(--color-text-secondary);
  margin-top: var(--spacing-sm);
}

.form-text.error {
  color: var(--color-danger);
}

.form-text.success {
  color: var(--color-success);
}

/* ============================================================
   7. ALERT & NOTIFICATION COMPONENTS
   ============================================================ */

.alert {
  padding: var(--spacing-lg);
  border-radius: var(--radius-lg);
  border: 1px solid;
  margin-bottom: var(--spacing-lg);
  display: flex;
  align-items: flex-start;
  gap: var(--spacing-md);
}

.alert-icon {
  flex-shrink: 0;
  font-size: 20px;
  display: flex;
  align-items: center;
}

.alert-content {
  flex: 1;
}

.alert-title {
  font-weight: var(--font-weight-semibold);
  margin-bottom: var(--spacing-sm);
}

/* Alert Variants */
.alert-success {
  background-color: var(--color-success-light);
  border-color: var(--color-success);
  color: #065f46;
}

.alert-warning {
  background-color: var(--color-warning-light);
  border-color: var(--color-warning);
  color: #78350f;
}

.alert-danger {
  background-color: var(--color-danger-light);
  border-color: var(--color-danger);
  color: #7f1d1d;
}

.alert-info {
  background-color: var(--color-info-light);
  border-color: var(--color-info);
  color: #164e63;
}

/* Badge Component */
.badge {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: var(--spacing-xs) var(--spacing-md);
  font-size: var(--font-size-xs);
  font-weight: var(--font-weight-semibold);
  border-radius: var(--radius-full);
  background-color: var(--color-primary-light);
  color: #ffffff;
  white-space: nowrap;
}

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

.badge-success {
  background-color: var(--color-success);
}

.badge-warning {
  background-color: var(--color-warning);
}

.badge-danger {
  background-color: var(--color-danger);
}

.badge-neutral {
  background-color: var(--color-text-secondary);
}

.badge-outline {
  background-color: transparent;
  border: 1px solid currentColor;
  color: var(--color-text-secondary);
}

/* ============================================================
   8. TABLE COMPONENTS
   ============================================================ */

.table {
  width: 100%;
  border-collapse: collapse;
  margin-bottom: var(--spacing-lg);
}

.table thead {
  background-color: var(--color-bg-hover);
  border-bottom: 1px solid var(--color-border);
}

.table thead th {
  padding: var(--spacing-md);
  text-align: left;
  font-weight: var(--font-weight-semibold);
  font-size: var(--font-size-sm);
  color: var(--color-text-primary);
}

.table tbody td {
  padding: var(--spacing-md);
  border-bottom: 1px solid var(--color-border-light);
  font-size: var(--font-size-sm);
}

.table tbody tr:hover {
  background-color: var(--color-bg-hover);
}

.table tbody tr:last-child td {
  border-bottom: none;
}

/* ============================================================
   9. MODAL COMPONENT
   ============================================================ */

.modal {
  display: none;
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background-color: rgba(0, 0, 0, 0.5);
  z-index: var(--z-modal-backdrop);
  align-items: center;
  justify-content: center;
}

.modal.active {
  display: flex;
}

.modal-content {
  background-color: var(--color-bg-surface);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-xl);
  max-width: 500px;
  width: 90%;
  max-height: 90vh;
  overflow-y: auto;
  z-index: var(--z-modal);
}

.modal-header {
  padding: var(--spacing-lg);
  border-bottom: 1px solid var(--color-border);
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.modal-header h5 {
  font-size: var(--font-size-lg);
  font-weight: var(--font-weight-semibold);
}

.modal-body {
  padding: var(--spacing-lg);
}

.modal-footer {
  padding: var(--spacing-lg);
  border-top: 1px solid var(--color-border);
  display: flex;
  justify-content: flex-end;
  gap: var(--spacing-md);
}

/* ============================================================
   10. UTILITY CLASSES
   ============================================================ */

/* Spacing Utilities */
.m-0 { margin: 0; }
.m-xs { margin: var(--spacing-xs); }
.m-sm { margin: var(--spacing-sm); }
.m-md { margin: var(--spacing-md); }
.m-lg { margin: var(--spacing-lg); }
.m-xl { margin: var(--spacing-xl); }
.m-2xl { margin: var(--spacing-2xl); }

.mb-0 { margin-bottom: 0; }
.mb-xs { margin-bottom: var(--spacing-xs); }
.mb-sm { margin-bottom: var(--spacing-sm); }
.mb-md { margin-bottom: var(--spacing-md); }
.mb-lg { margin-bottom: var(--spacing-lg); }
.mb-xl { margin-bottom: var(--spacing-xl); }
.mb-2xl { margin-bottom: var(--spacing-2xl); }

.mt-0 { margin-top: 0; }
.mt-xs { margin-top: var(--spacing-xs); }
.mt-sm { margin-top: var(--spacing-sm); }
.mt-md { margin-top: var(--spacing-md); }
.mt-lg { margin-top: var(--spacing-lg); }
.mt-xl { margin-top: var(--spacing-xl); }
.mt-2xl { margin-top: var(--spacing-2xl); }

.p-0 { padding: 0; }
.p-xs { padding: var(--spacing-xs); }
.p-sm { padding: var(--spacing-sm); }
.p-md { padding: var(--spacing-md); }
.p-lg { padding: var(--spacing-lg); }
.p-xl { padding: var(--spacing-xl); }
.p-2xl { padding: var(--spacing-2xl); }

/* Text Alignment */
.text-left { text-align: left; }
.text-center { text-align: center; }
.text-right { text-align: right; }

/* Display Utilities */
.d-none { display: none; }
.d-block { display: block; }
.d-flex { display: flex; }
.d-grid { display: grid; }
.d-inline { display: inline; }
.d-inline-flex { display: inline-flex; }
.d-inline-block { display: inline-block; }

.flex-center {
  display: flex;
  align-items: center;
  justify-content: center;
}

.flex-between {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.flex-col {
  flex-direction: column;
}

.gap-sm { gap: var(--spacing-sm); }
.gap-md { gap: var(--spacing-md); }
.gap-lg { gap: var(--spacing-lg); }
.gap-xl { gap: var(--spacing-xl); }

/* Colors */
.text-primary { color: var(--color-primary); }
.text-success { color: var(--color-success); }
.text-warning { color: var(--color-warning); }
.text-danger { color: var(--color-danger); }
.text-info { color: var(--color-info); }

.bg-primary-light { background-color: var(--color-primary-subtle); }
.bg-success-light { background-color: var(--color-success-light); }
.bg-warning-light { background-color: var(--color-warning-light); }
.bg-danger-light { background-color: var(--color-danger-light); }

/* Border Utilities */
.border { border: 1px solid var(--color-border); }
.border-top { border-top: 1px solid var(--color-border); }
.border-bottom { border-bottom: 1px solid var(--color-border); }
.border-left { border-left: 1px solid var(--color-border); }
.border-right { border-right: 1px solid var(--color-border); }

.rounded-sm { border-radius: var(--radius-sm); }
.rounded-md { border-radius: var(--radius-md); }
.rounded-lg { border-radius: var(--radius-lg); }
.rounded-xl { border-radius: var(--radius-xl); }
.rounded-full { border-radius: var(--radius-full); }

/* Shadow Utilities */
.shadow-none { box-shadow: var(--shadow-none); }
.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); }

/* Opacity */
.opacity-50 { opacity: 0.5; }
.opacity-75 { opacity: 0.75; }
.opacity-100 { opacity: 1; }

/* ============================================================
   11. RESPONSIVE UTILITIES
   ============================================================ */

@media (max-width: 768px) {
  .d-md-none { display: none !important; }
  .d-md-block { display: block !important; }
  .d-md-flex { display: flex !important; }
  .d-md-grid { display: grid !important; }
}

@media (min-width: 769px) {
  .d-lg-none { display: none !important; }
  .d-lg-block { display: block !important; }
  .d-lg-flex { display: flex !important; }
  .d-lg-grid { display: grid !important; }
}

/* ============================================================
   12. ANIMATION UTILITIES
   ============================================================ */

@keyframes fadeIn {
  from {
    opacity: 0;
  }
  to {
    opacity: 1;
  }
}

@keyframes slideInUp {
  from {
    transform: translateY(10px);
    opacity: 0;
  }
  to {
    transform: translateY(0);
    opacity: 1;
  }
}

@keyframes slideInDown {
  from {
    transform: translateY(-10px);
    opacity: 0;
  }
  to {
    transform: translateY(0);
    opacity: 1;
  }
}

.animate-fade-in {
  animation: fadeIn var(--transition-normal);
}

.animate-slide-in-up {
  animation: slideInUp var(--transition-normal);
}

.animate-slide-in-down {
  animation: slideInDown var(--transition-normal);
}