/* ==================== 
   MODERN DESIGN SYSTEM 
   ==================== */

/* CSS Variables for consistent theming */
:root {
  /* Colors - Warm Coral & Beige Theme */
  --color-primary: #E8876B;
  --color-primary-50: #FBF8F5;
  --color-primary-100: #F5F0EB;
  --color-primary-200: #F0E6DD;
  --color-primary-300: #E8C4B0;
  --color-primary-400: #E89E84;
  --color-primary-500: #E8876B;
  --color-primary-600: #e07a5e;
  --color-primary-700: #d4785f;
  --color-primary-800: #c96d54;

  --color-secondary: #2D4B73;
  --color-secondary-50: #f0f4f8;
  --color-secondary-100: #e1eaf2;
  --color-secondary-500: #2D4B73;
  --color-secondary-600: #284166;
  --color-secondary-700: #233759;

  --color-accent: #D9BA23;
  --color-accent-50: #fdfaf0;
  --color-accent-100: #faf5e1;
  --color-accent-500: #D9BA23;
  --color-accent-600: #c4a720;

  --color-warning: #F59E0B;
  --color-warning-50: #FFFBEB;
  --color-warning-100: #FEF3C7;
  --color-warning-500: #F59E0B;

  --color-danger: #EF4444;
  --color-danger-50: #FEF2F2;
  --color-danger-100: #FEE2E2;
  --color-danger-200: #FECACA;
  --color-danger-500: #EF4444;
  --color-danger-600: #DC2626;
  --color-danger-700: #B91C1C;

  --color-success: #22C55E;
  --color-success-50: #F0FDF4;
  --color-success-100: #DCFCE7;
  --color-success-500: #22C55E;
  --color-success-600: #16A34A;
  --color-success-700: #15803D;

  /* Neutral Colors - Warm Tones */
  --color-white: #ffffff;
  --color-gray-50: #FAF7F4;
  --color-gray-100: #F5F0EB;
  --color-gray-200: #E5E0DB;
  --color-gray-300: #D1CBC4;
  --color-gray-400: #9C958E;
  --color-gray-500: #6B6560;
  --color-gray-600: #4A4540;
  --color-gray-700: #363230;
  --color-gray-800: #1A1A2E;
  --color-gray-900: #0f0f1a;
  
  /* Calendar Event Colors - Warm Theme */
  --color-event-1: rgba(232, 135, 107, 0.45);  /* Coral */
  --color-event-2: rgba(219, 112, 128, 0.40);  /* Rose */
  --color-event-3: rgba(198, 130, 95, 0.45);   /* Terracotta */
  --color-event-4: rgba(217, 176, 65, 0.45);   /* Amber */
  --color-event-5: rgba(195, 170, 120, 0.50);  /* Sand */
  --color-event-6: rgba(140, 170, 130, 0.45);  /* Sage */
  --color-event-7: rgba(110, 165, 160, 0.40);  /* Teal */
  --color-event-8: rgba(150, 140, 185, 0.40);  /* Lavender */
  --color-event-9: rgba(185, 130, 155, 0.40);  /* Mauve */
  --color-event-10: rgba(120, 150, 185, 0.40); /* Blue */
  --color-event-11: rgba(235, 165, 100, 0.45); /* Apricot */
  --color-event-12: rgba(165, 110, 140, 0.40); /* Berry */

  /* Gradients */
  --gradient-primary: linear-gradient(135deg, #E8876B 0%, #e07a5e 100%);
  --gradient-secondary: linear-gradient(135deg, var(--color-secondary-600) 0%, var(--color-secondary-700) 100%);
  --gradient-accent: linear-gradient(135deg, var(--color-accent-600) 0%, var(--color-accent-500) 100%);
  --gradient-glass: linear-gradient(135deg, rgba(255,255,255,0.1) 0%, rgba(255,255,255,0.05) 100%);
  
  /* 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 -1px rgba(0, 0, 0, 0.1);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -2px rgba(0, 0, 0, 0.1);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -4px rgba(0, 0, 0, 0.1);
  --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 8px 10px -6px rgba(0, 0, 0, 0.1);
  --shadow-2xl: 0 25px 50px -12px rgba(0, 0, 0, 0.25);
  --shadow-glow: 0 0 20px rgba(232, 135, 107, 0.15);
  
  /* Border Radius */
  --radius-sm: 0.375rem;
  --radius-md: 0.5rem;
  --radius-lg: 0.75rem;
  --radius-xl: 1rem;
  --radius-2xl: 1.5rem;
  --radius-full: 9999px;
  
  /* Typography */
  --font-family-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --font-weight-normal: 400;
  --font-weight-medium: 500;
  --font-weight-semibold: 600;
  --font-weight-bold: 700;
  
  /* Spacing */
  --space-xs: 0.25rem;
  --space-sm: 0.5rem;
  --space-md: 1rem;
  --space-lg: 1.5rem;
  --space-xl: 2rem;
  --space-2xl: 3rem;
  
  /* Transitions */
  --transition-fast: 150ms ease-in-out;
  --transition-normal: 250ms ease-in-out;
  --transition-slow: 350ms ease-in-out;
}

/* Reset and Base Styles */
*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  font-size: 16px;
  line-height: 1.5;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: var(--font-family-sans);
  font-weight: var(--font-weight-normal);
  color: var(--color-gray-800);
  background: #F5F0EB;
  margin: 0;
  padding: 0;
  min-height: 100vh;
  transition: var(--transition-normal);
}

/* Enhanced Scrollbar Styles */
::-webkit-scrollbar {
  width: 6px;
  height: 6px;
}

::-webkit-scrollbar-track {
  background: var(--color-gray-100);
  border-radius: var(--radius-full);
}

::-webkit-scrollbar-thumb {
  background: var(--color-gray-300);
  border-radius: var(--radius-full);
  transition: var(--transition-fast);
}

::-webkit-scrollbar-thumb:hover {
  background: var(--color-gray-400);
}

::-webkit-scrollbar-corner {
  background: var(--color-gray-100);
}

/* Modern Card Components */
.card {
  background: var(--color-primary-50);
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-sm);
  border: 1px solid var(--color-gray-200);
  transition: var(--transition-normal);
  overflow: hidden;
}

.card:hover {
  /* Hover animations removed */
}

.card-glass {
  background: rgba(255, 255, 255, 0.85);
  backdrop-filter: blur(12px);
  border: 1px solid rgba(255, 255, 255, 0.2);
}

/* Enhanced Navigation */
.nav-modern {
  background: rgba(255, 255, 255, 0.97);
  backdrop-filter: blur(20px);
  border-bottom: 1px solid #E5E0DB;
  transition: var(--transition-normal);
}

.nav-item {
  position: relative;
  display: inline-flex;
  align-items: center;
  gap: var(--space-sm);
  padding: var(--space-sm) var(--space-lg);
  border-radius: var(--radius-full);
  font-weight: var(--font-weight-medium);
  color: var(--color-gray-600);
  text-decoration: none;
  transition: var(--transition-fast);
  overflow: hidden;
  white-space: nowrap;
  min-width: fit-content;
}

.nav-item::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: var(--gradient-primary);
  opacity: 0;
  transition: var(--transition-fast);
  z-index: -1;
}

.nav-item:hover::before,
.nav-item.active::before {
  opacity: 1;
}

.nav-item:hover,
.nav-item.active {
  color: var(--color-white);
  transform: translateY(-1px);
}

/* Navigation Group Dropdown */
.nav-modern .flex.items-center.space-x-1 {
  overflow: visible !important;
}

.nav-group {
  position: relative;
}

.nav-group-trigger {
  cursor: pointer;
  user-select: none;
}

.nav-chevron {
  transition: transform 0.2s ease;
  opacity: 0.7;
}

.nav-group:hover .nav-chevron {
  transform: rotate(180deg);
  opacity: 1;
}

.nav-dropdown {
  display: none;
  position: absolute;
  top: 100%;
  left: 50%;
  transform: translateX(-50%);
  background: var(--color-white);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-lg);
  border: 1px solid var(--color-gray-200);
  min-width: 180px;
  z-index: 60;
  padding: 6px 0;
  padding-top: 10px;
  animation: dropdownFadeIn 0.15s ease;
}

/* hover 연결을 위한 투명 브릿지 */
.nav-dropdown::before {
  content: '';
  position: absolute;
  top: -6px;
  left: 0;
  right: 0;
  height: 10px;
}

@keyframes dropdownFadeIn {
  from { opacity: 0; transform: translateX(-50%) translateY(-4px); }
  to   { opacity: 1; transform: translateX(-50%) translateY(0); }
}

.nav-group:hover .nav-dropdown {
  display: block;
}

.nav-dropdown-item {
  display: block;
  padding: 8px 16px;
  color: var(--color-gray-600);
  text-decoration: none;
  font-size: 0.875rem;
  font-weight: var(--font-weight-medium);
  white-space: nowrap;
  transition: var(--transition-fast);
}

.nav-dropdown-item:hover {
  background: var(--color-primary-50);
  color: var(--color-primary-700);
}

.nav-dropdown-item.active {
  background: var(--color-primary-100);
  color: var(--color-primary-700);
  font-weight: var(--font-weight-semibold);
}

/* Modern Button System */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-sm);
  padding: var(--space-sm) var(--space-lg);
  border: none;
  border-radius: var(--radius-lg);
  font-family: inherit;
  font-weight: var(--font-weight-semibold);
  font-size: 0.875rem;
  line-height: 1.25rem;
  text-decoration: none;
  cursor: pointer;
  transition: var(--transition-fast);
  position: relative;
  overflow: hidden;
}

.btn::before {
  content: '';
  position: absolute;
  top: 0;
  left: -100%;
  width: 100%;
  height: 100%;
  background: linear-gradient(90deg, transparent, rgba(255,255,255,0.2), transparent);
  transition: var(--transition-normal);
}

.btn:hover::before {
  left: 100%;
}

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

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

.btn-secondary {
  background: var(--color-secondary-100);
  color: var(--color-gray-900);
  border: 1px solid var(--color-secondary-200);
  box-shadow: var(--shadow-sm);
}

.btn-secondary:hover {
  background: var(--color-gray-50);
  box-shadow: var(--shadow-md);
  transform: translateY(-1px);
}

.btn-accent {
  background: var(--gradient-accent);
  color: var(--color-gray-900);
  box-shadow: var(--shadow-md);
}

.btn-success {
  background: var(--color-success-600);
  color: var(--color-gray-900);
}

.btn-success:hover {
  background: var(--color-success-700);
  transform: translateY(-1px);
}

.btn-warning {
  background: var(--color-warning-500);
  color: var(--color-gray-900);
}

.btn-danger {
  background: var(--color-danger-600);
  color: var(--color-gray-900);
}

.btn-danger:hover {
  background: var(--color-danger-700);
}

/* Enhanced Form Elements */
.form-input {
  width: 100%;
  padding: var(--space-sm) var(--space-md);
  border: 1px solid var(--color-gray-300);
  border-radius: var(--radius-lg);
  font-family: inherit;
  font-size: 0.875rem;
  background: var(--color-primary-50);
  transition: var(--transition-fast);
}

.form-input:focus {
  outline: none;
  border-color: #E8876B;
  box-shadow: 0 0 0 3px rgba(232, 135, 107, 0.15);
  transform: translateY(-1px);
}

.form-textarea {
  resize: vertical;
  min-height: 100px;
}

.form-select {
  background-image: url("data:image/svg+xml,%3csvg xmlns='http://www.w3.org/2000/svg' fill='none' viewBox='0 0 20 20'%3e%3cpath stroke='%236b7280' stroke-linecap='round' stroke-linejoin='round' stroke-width='1.5' d='M6 8l4 4 4-4'/%3e%3c/svg%3e");
  background-position: right 0.5rem center;
  background-repeat: no-repeat;
  background-size: 1.5em 1.5em;
  padding-right: 2.5rem;
}

/* Enhanced Modal System */
.modal-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.6);
  backdrop-filter: blur(8px);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 1000;
  opacity: 1;
  visibility: visible;
  transition: var(--transition-normal);
}

.modal-overlay.hidden {
  opacity: 0;
  visibility: hidden;
  pointer-events: none;
}

.modal-overlay.active {
  opacity: 1;
  visibility: visible;
}

.modal {
  background: #FFFFFF;
  border-radius: var(--radius-2xl);
  box-shadow: var(--shadow-2xl);
  max-width: 90vw;
  max-height: 90vh;
  overflow: hidden;
  transform: scale(1) translateY(0);
  transition: var(--transition-normal);
}

.modal-overlay.hidden .modal {
  transform: scale(0.95) translateY(20px);
}

.modal-overlay.active .modal {
  transform: scale(1) translateY(0);
}

/* Enhanced Student List */
.student-list-item {
  padding: var(--space-md);
  border-radius: var(--radius-lg);
  transition: var(--transition-fast);
  cursor: pointer;
  border: 1px solid transparent;
}

.student-list-item:hover {
  background: var(--color-gray-50);
  transform: translateX(4px);
}

.student-list-item.active {
  background: var(--color-primary-50);
  border-color: var(--color-primary-200);
  font-weight: var(--font-weight-semibold);
  color: var(--color-primary-700);
  box-shadow: var(--shadow-sm);
}

/* Enhanced Student Cards */
.student-card {
  background: var(--color-accent-50);
  border-radius: var(--radius-xl);
  border: 1px solid var(--color-gray-200);
  box-shadow: var(--shadow-sm);
  transition: var(--transition-normal);
  overflow: hidden;
  position: relative;
}

.student-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 3px;
  background: var(--gradient-primary);
  opacity: 0;
  transition: var(--transition-fast);
}

.student-card:hover {
  /* Hover animations removed */
}

.student-card:hover::before {
  /* Hover animations removed */
}

.student-card.highlight {
  border-color: var(--color-primary-300);
  box-shadow: var(--shadow-glow);
  background: var(--color-primary-50);
}

/* Status System */
.status-btn {
  padding: var(--space-xs) var(--space-md);
  border-radius: var(--radius-full);
  font-size: 0.75rem;
  font-weight: var(--font-weight-semibold);
  border: none;
  cursor: pointer;
  transition: var(--transition-fast);
  text-transform: uppercase;
  letter-spacing: 0.025em;
}

.status-present {
  background: var(--color-success-100);
  color: var(--color-success-700);
}

.status-absent {
  background: var(--color-gray-200);
  color: var(--color-gray-600);
}

.status-complete {
  background: var(--color-primary-100);
  color: var(--color-primary-700);
}

.status-incomplete {
  background: var(--color-warning-100);
  color: var(--color-warning-700);
}

/* Loading States */
.loading {
  position: relative;
  overflow: hidden;
}

.loading::after {
  content: '';
  position: absolute;
  top: 0;
  left: -100%;
  width: 100%;
  height: 100%;
  background: linear-gradient(90deg, transparent, rgba(255,255,255,0.6), transparent);
  animation: loading 1.5s infinite;
}

@keyframes loading {
  0% { left: -100%; }
  100% { left: 100%; }
}

/* Fade In Animations */
.fade-in {
  animation: fadeIn 0.6s ease-out;
}

.fade-in-up {
  animation: fadeInUp 0.8s ease-out;
}

.fade-in-left {
  animation: fadeInLeft 0.6s ease-out;
}

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

@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(30px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes fadeInLeft {
  from {
    opacity: 0;
    transform: translateX(-30px);
  }
  to {
    opacity: 1;
    transform: translateX(0);
  }
}

/* Pulse Animation */
.pulse {
  animation: pulse 2s infinite;
}

@keyframes pulse {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.7; }
}

/* Toast Notifications */
.toast {
  position: fixed;
  bottom: 2.5rem;
  left: 50%;
  transform: translateX(-50%) translateY(20px);
  background: var(--color-gray-800);
  color: var(--color-white);
  padding: var(--space-md) var(--space-xl);
  border-radius: var(--radius-xl);
  box-shadow: 0 8px 24px rgba(0,0,0,0.25);
  font-weight: var(--font-weight-semibold);
  font-size: 0.95rem;
  backdrop-filter: blur(12px);
  z-index: 1100;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.3s, transform 0.3s;
}

.toast.show {
  opacity: 1;
  pointer-events: auto;
  transform: translateX(-50%) translateY(0);
}

.toast.success {
  background: rgba(232, 135, 107, 0.97);
}

.toast.warning {
  background: rgba(217, 119, 6, 0.95);
}

.toast.error {
  background: rgba(220, 38, 38, 0.95);
}

/* Modal Prevention */
body.modal-open {
  overflow: hidden;
}

/* Enhanced Mobile Responsiveness */
@media (max-width: 768px) {
  :root {
    --space-xs: 0.25rem;
    --space-sm: 0.375rem;
    --space-md: 0.75rem;
    --space-lg: 1rem;
    --space-xl: 1.5rem;
  }

  body {
    font-size: 14px;
    padding: 0 var(--space-sm);
  }

  .card {
    border-radius: var(--radius-lg);
    margin-bottom: var(--space-md);
  }

  .btn {
    padding: var(--space-md) var(--space-lg);
    font-size: 0.875rem;
  }

  .nav-item {
    padding: var(--space-sm) var(--space-md);
    margin: var(--space-xs);
  }

  .student-list-item {
    padding: var(--space-sm) var(--space-md);
  }

  .student-list-item.active {
    font-weight: var(--font-weight-bold);
  }

  .modal {
    margin: var(--space-md);
    max-width: calc(100vw - 2rem);
  }
}

/* Dark mode: disabled (light mode only) */

/* Reduced motion for accessibility */
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}