/* ============================================================
   QRENA v6 - Mode Selection Screen Styles
   ============================================================
   Purpose: Styling for teacher mode selection (QR Arena vs SOL)
   Responsive: Desktop (1920x1080), iPad Landscape, iPad Portrait
   Design: Liquid Glass with mode-specific gradients
   ============================================================ */

/* ======================== CSS VARIABLES ======================== */

:root {
  /* QR Arena Mode - Energetic Blue */
  --arena-primary: #3b82f6;
  --arena-primary-hover: #2563eb;
  --arena-accent: #8b5cf6;
  --arena-gradient: linear-gradient(135deg, #3b82f6, #8b5cf6);
  --arena-glow: rgba(59, 130, 246, 0.4);

  /* SOL Mode - Calm Green */
  --sol-primary: #10b981;
  --sol-primary-hover: #059669;
  --sol-accent: #14b8a6;
  --sol-gradient: linear-gradient(135deg, #10b981, #14b8a6);
  --sol-glow: rgba(16, 185, 129, 0.4);

  /* Badges */
  --badge-recommended: #f59e0b;
  --badge-new: #10b981;

  /* Schreibtisch-Shortcut - neutraler Brand-Indigo, bündelt beide Modi */
  --desk-primary: #6366f1;
  --desk-accent: #8b5cf6;
  --desk-glow: rgba(99, 102, 241, 0.25);

  /* Spacing */
  --spacing-xs: 0.5rem;
  --spacing-sm: 1rem;
  --spacing-md: 1.5rem;
  --spacing-lg: 2rem;
  --spacing-xl: 3rem;

  /* Border Radius */
  --radius-sm: 0.5rem;
  --radius-md: 1rem;
  --radius-lg: 1.5rem;
  --radius-xl: 2rem;

  /* Transitions */
  --transition-fast: 150ms ease;
  --transition-normal: 250ms ease;
  --transition-slow: 400ms ease;
}

/* ======================== LAYOUT ======================== */

.mode-selection-page {
  min-height: 100vh;
  position: relative;
  overflow-x: hidden;
  background: linear-gradient(135deg, #1f2937 0%, #111827 100%);
}

.mode-selection-container {
  max-width: 1400px;
  margin: 0 auto;
  padding: var(--spacing-lg);
  position: relative;
  z-index: 10;
}

/* ======================== HEADER ======================== */

.mode-selection-header {
  text-align: center;
  margin-bottom: var(--spacing-xl);
  animation: fadeInDown 0.6s ease;
}

.header-logo {
  margin-bottom: var(--spacing-md);
}

.header-logo img {
  width: 80px;
  height: 80px;
  border-radius: 50%;
  box-shadow: 0 10px 40px rgba(59, 130, 246, 0.3);
  transition: transform var(--transition-normal);
}

.header-logo img:hover {
  transform: scale(1.05);
}

.header-title {
  font-size: 2.5rem;
  font-weight: 700;
  margin-bottom: var(--spacing-sm);
  background: linear-gradient(135deg, #ffffff, #cbd5e1);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.header-greeting {
  font-size: 1.25rem;
  color: #94a3b8;
  margin: 0;
}

.header-greeting strong {
  color: #e2e8f0;
  font-weight: 600;
}

/* ======================== MODE CARDS GRID ======================== */

.mode-cards-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: var(--spacing-sm);
  margin-bottom: var(--spacing-xl);
}

/* ======================== MODE CARD ======================== */

.mode-card {
  position: relative;
  background: rgba(30, 41, 59, 0.6);
  backdrop-filter: blur(20px);
  border: 1px solid rgba(255, 255, 255, 0.1);
  border-radius: var(--radius-xl);
  padding: 1.25rem;
  cursor: pointer;
  transition: all var(--transition-normal);
  outline: none;
}

/* Color-coded top border per arena type */
.mode-card[data-mode="arena"] {
  border-top: 2px solid rgba(99, 102, 241, 0.55);
}
.mode-card[data-mode="sol"] {
  border-top: 2px solid rgba(16, 185, 129, 0.55);
}

.mode-card::before {
  content: '';
  position: absolute;
  inset: 0;
  border-radius: var(--radius-xl);
  padding: 2px;
  background: linear-gradient(135deg, rgba(255, 255, 255, 0.1), rgba(255, 255, 255, 0.05));
  -webkit-mask: linear-gradient(#fff 0 0) content-box, linear-gradient(#fff 0 0);
  -webkit-mask-composite: xor;
  mask-composite: exclude;
  opacity: 0;
  transition: opacity var(--transition-normal);
}

.mode-card:hover::before,
.mode-card:focus::before {
  opacity: 1;
}

/* Arena Mode Card */
.mode-card[data-mode="arena"]:hover,
.mode-card[data-mode="arena"]:focus {
  transform: translateY(-8px);
  box-shadow: 0 20px 60px var(--arena-glow);
  border-color: var(--arena-primary);
}

/* SOL Mode Card */
.mode-card[data-mode="sol"]:hover,
.mode-card[data-mode="sol"]:focus {
  transform: translateY(-8px);
  box-shadow: 0 20px 60px var(--sol-glow);
  border-color: var(--sol-primary);
}

.mode-card-inner {
  position: relative;
}

/* ======================== CARD HEADER ======================== */

.mode-card-header {
  text-align: left;
  margin-bottom: var(--spacing-xs);
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.mode-icon {
  font-size: 2.2rem;
  margin-bottom: 0;
  filter: drop-shadow(0 4px 20px rgba(59, 130, 246, 0.3));
  animation: none;
  flex-shrink: 0;
}

.mode-logo-img {
  width: 44px;
  height: 44px;
  object-fit: contain;
  display: block;
}

@keyframes float {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-10px); }
}

.mode-title {
  font-size: 1.35rem;
  font-weight: 700;
  margin-bottom: 0;
  color: #f1f5f9;
}

.mode-subtitle {
  font-size: 0.82rem;
  color: #94a3b8;
  margin: 0;
}

/* ======================== FEATURES LIST ======================== */

.mode-features {
  list-style: none;
  padding: 0;
  margin: 0.5rem 0 0.75rem 0;
}

.feature-item {
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
  padding: 0.35rem 0.6rem;
  margin-bottom: 0.25rem;
  background: rgba(255, 255, 255, 0.03);
  border-radius: var(--radius-md);
  transition: background var(--transition-fast);
}

.feature-item:hover {
  background: rgba(255, 255, 255, 0.06);
}

.feature-icon {
  font-size: 1rem;
  flex-shrink: 0;
}

.feature-text {
  color: #cbd5e1;
  font-size: 0.82rem;
}

/* ======================== CTA BUTTON ======================== */

.mode-cta {
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: var(--spacing-sm);
  padding: 0.65rem 1.5rem;
  font-size: 0.92rem;
  font-weight: 600;
  border: none;
  border-radius: var(--radius-md);
  cursor: pointer;
  transition: all var(--transition-normal);
  position: relative;
  overflow: hidden;
}

/* Arena CTA */
.mode-card[data-mode="arena"] .mode-cta {
  background: var(--arena-gradient);
  color: white;
}

.mode-card[data-mode="arena"] .mode-cta:hover {
  transform: translateY(-2px);
  box-shadow: 0 10px 30px var(--arena-glow);
}

/* SOL CTA */
.mode-card[data-mode="sol"] .mode-cta {
  background: var(--sol-gradient);
  color: white;
}

.mode-card[data-mode="sol"] .mode-cta:hover {
  transform: translateY(-2px);
  box-shadow: 0 10px 30px var(--sol-glow);
}

.mode-cta::before {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, rgba(255, 255, 255, 0.2), transparent);
  opacity: 0;
  transition: opacity var(--transition-normal);
}

.mode-cta:hover::before {
  opacity: 1;
}

.cta-text {
  position: relative;
  z-index: 1;
}

.cta-icon {
  position: relative;
  z-index: 1;
  font-size: 1.5rem;
  transition: transform var(--transition-normal);
}

.mode-cta:hover .cta-icon {
  transform: translateX(4px);
}

/* ======================== BADGES ======================== */

.mode-badge {
  position: absolute;
  top: var(--spacing-md);
  right: var(--spacing-md);
  padding: 0.5rem 1rem;
  border-radius: var(--radius-lg);
  font-size: 0.875rem;
  font-weight: 600;
  color: white;
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.2);
}

.mode-badge.recommended {
  background: linear-gradient(135deg, #f59e0b, #f97316);
}

.mode-badge.new {
  background: linear-gradient(135deg, #10b981, #14b8a6);
}

.badge-text {
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

/* ======================== TIPS SECTION ======================== */

.tips-section {
  margin-bottom: var(--spacing-xl);
  animation: fadeInUp 0.8s ease;
}

.tip-card {
  display: flex;
  align-items: center;
  gap: var(--spacing-md);
  padding: var(--spacing-lg);
  background: rgba(59, 130, 246, 0.1);
  border: 1px solid rgba(59, 130, 246, 0.2);
  border-radius: var(--radius-lg);
  backdrop-filter: blur(10px);
}

.tip-icon {
  font-size: 2rem;
  flex-shrink: 0;
}

.tip-text {
  color: #cbd5e1;
  margin: 0;
  font-size: 1rem;
  line-height: 1.6;
}

.tip-text strong {
  color: #f1f5f9;
  font-weight: 600;
}

/* ======================== RECENT SESSIONS ======================== */

.recent-sessions {
  animation: fadeInUp 1s ease;
}

.recent-sessions.hidden {
  display: none;
}

.section-title {
  font-size: 1.5rem;
  font-weight: 600;
  color: #f1f5f9;
  margin-bottom: var(--spacing-md);
}

.sessions-list {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: var(--spacing-md);
}

/* ======================== FOOTER ======================== */

.mode-selection-footer {
  text-align: center;
  padding: var(--spacing-lg) 0;
  animation: fadeInUp 1.2s ease;
}

.btn-ghost {
  display: inline-flex;
  align-items: center;
  gap: var(--spacing-xs);
  padding: 0.75rem 1.5rem;
  background: transparent;
  border: 1px solid rgba(255, 255, 255, 0.1);
  border-radius: var(--radius-md);
  color: #94a3b8;
  font-size: 1rem;
  cursor: pointer;
  transition: all var(--transition-normal);
}

.btn-ghost:hover {
  background: rgba(255, 255, 255, 0.05);
  border-color: rgba(255, 255, 255, 0.2);
  color: #cbd5e1;
  transform: translateY(-2px);
}

/* ======================== ANIMATIONS ======================== */

@keyframes fadeInDown {
  from {
    opacity: 0;
    transform: translateY(-20px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(20px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* ======================== RESPONSIVE DESIGN ======================== */

/* iPad Landscape (1024x768) */
@media (max-width: 1024px) {
  .mode-cards-grid {
    grid-template-columns: 1fr;
    max-width: 600px;
    margin: 0 auto var(--spacing-xl);
  }

  .desk-shortcut-row {
    grid-template-columns: 1fr;
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
  }

  .header-title {
    font-size: 2rem;
  }

  .mode-icon {
    font-size: 3.5rem;
  }

  .mode-logo-img {
    width: 52px;
    height: 52px;
  }

  .mode-title {
    font-size: 1.75rem;
  }
}

/* iPad Portrait (768x1024) */
@media (max-width: 768px) {
  .mode-selection-container {
    padding: var(--spacing-md);
  }

  .mode-cards-grid {
    grid-template-columns: 1fr;
    gap: var(--spacing-md);
  }

  .header-title {
    font-size: 1.75rem;
  }

  .header-greeting {
    font-size: 1rem;
  }

  .mode-card {
    padding: var(--spacing-md);
  }

  .mode-icon {
    font-size: 3rem;
  }

  .mode-logo-img {
    width: 48px;
    height: 48px;
  }

  .mode-title {
    font-size: 1.5rem;
  }

  .mode-cta {
    padding: 0.875rem 1.5rem;
    font-size: 1rem;
  }

  .tip-card {
    flex-direction: column;
    text-align: center;
  }

  .sessions-list {
    grid-template-columns: 1fr;
  }
}

/* iPhone/Small Devices (< 480px) */
@media (max-width: 480px) {
  .mode-selection-container {
    padding: var(--spacing-sm);
  }

  .header-logo img {
    width: 60px;
    height: 60px;
  }

  .header-title {
    font-size: 1.5rem;
  }

  .mode-icon {
    font-size: 2.5rem;
  }

  .mode-logo-img {
    width: 40px;
    height: 40px;
  }

  .mode-title {
    font-size: 1.25rem;
  }

  .mode-subtitle {
    font-size: 0.875rem;
  }

  .feature-text {
    font-size: 0.875rem;
  }

  .mode-badge {
    position: static;
    display: inline-block;
    margin-top: var(--spacing-sm);
  }
}

/* ======================== ACCESSIBILITY ======================== */

/* Focus visible for keyboard navigation */
.mode-card:focus-visible {
  outline: 2px solid var(--arena-primary);
  outline-offset: 4px;
}

.mode-cta:focus-visible {
  outline: 2px solid white;
  outline-offset: 2px;
}

.btn-ghost:focus-visible {
  outline: 2px solid #94a3b8;
  outline-offset: 2px;
}

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

  .mode-icon {
    animation: none;
  }
}

/* High contrast mode support */
@media (prefers-contrast: high) {
  .mode-card {
    border-width: 2px;
  }

  .mode-cta {
    border: 2px solid white;
  }
}

/* ======================== SCHREIBTISCH-SHORTCUT (dezent) ======================== */

.desk-shortcut-row {
  display: grid;
  grid-template-columns: repeat(2, minmax(260px, 1fr));
  gap: var(--spacing-sm);
  margin-top: var(--spacing-lg);
}

.desk-shortcut-tile {
  display: flex;
  align-items: center;
  gap: 14px;
  flex-wrap: wrap;
  min-height: 56px;
  padding: 0.85rem 1.25rem;
  background: rgba(255, 255, 255, 0.04);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border: 1px solid rgba(255, 255, 255, 0.08);
  border-radius: 1rem;
  cursor: pointer;
  outline: none;
  transition: transform var(--transition-normal), box-shadow var(--transition-normal), border-color var(--transition-normal);
}

.desk-shortcut-tile:hover,
.desk-shortcut-tile:focus-visible {
  transform: translateY(-2px);
  border-color: rgba(99, 102, 241, 0.35);
  box-shadow: 0 8px 24px var(--desk-glow);
}

.desk-shortcut-tile:focus-visible {
  outline: 2px solid var(--desk-primary);
  outline-offset: 3px;
}

.desk-shortcut-tile:hover .desk-shortcut-chevron {
  transform: translateX(3px);
  color: var(--desk-primary);
}

.desk-shortcut-icon {
  width: 34px;
  height: 34px;
  border-radius: 10px;
  flex-shrink: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  background: rgba(99, 102, 241, 0.12);
  border: 1px solid rgba(99, 102, 241, 0.25);
  color: var(--desk-primary);
}

.desk-shortcut-text {
  flex: 1 1 200px;
  min-width: 160px;
}

.desk-shortcut-title {
  font-size: 0.95rem;
  font-weight: 700;
  color: rgba(255, 255, 255, 0.85);
  margin: 0;
}

.desk-shortcut-subtitle {
  font-size: 0.72rem;
  color: rgba(255, 255, 255, 0.42);
  margin: 2px 0 0;
}

.desk-shortcut-features {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 0;
  padding: 0;
  flex: 1 1 100%;
  order: 3;
}

.desk-feature-item {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 4px 10px 4px 8px;
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.03);
  border: 1px solid rgba(255, 255, 255, 0.06);
}

.desk-feature-icon {
  display: flex;
  flex-shrink: 0;
}

.desk-feature-text {
  font-size: 0.7rem;
  color: rgba(255, 255, 255, 0.55);
  white-space: nowrap;
}

.desk-feature-item--neutral .desk-feature-icon { color: rgba(255, 255, 255, 0.45); }
.desk-feature-item--orange .desk-feature-icon { color: #fb923c; }
.desk-feature-item--emerald .desk-feature-icon { color: #10b981; }

.desk-shortcut-chevron {
  flex-shrink: 0;
  margin-left: auto;
  color: rgba(255, 255, 255, 0.3);
  transition: transform var(--transition-normal), color var(--transition-normal);
}

@media (max-width: 768px) {
  .desk-shortcut-tile {
    padding: 0.75rem 1rem;
  }

  .desk-shortcut-features {
    gap: 6px;
  }
}

@media (max-width: 480px) {
  .desk-shortcut-subtitle {
    display: none;
  }

  .desk-feature-text {
    font-size: 0.65rem;
  }

  .desk-shortcut-tile {
    gap: 10px;
    padding: 0.7rem 0.9rem;
  }
}

/* ======================== PRINT STYLES ======================== */

@media print {
  .bg-layer,
  .noise,
  .bg-animation,
  .mode-selection-footer {
    display: none;
  }

  .mode-card {
    break-inside: avoid;
    border: 1px solid #000;
    box-shadow: none;
  }
}