/* ===================================================================
   YOGA VIDYA - Clean Digital Textbook & Exam Preparation Guide
   Paper 490E1110: Fundamentals and History of Yoga
   Simplified, High-Readability Exam Reader (No Notebook Lines)
   =================================================================== */

@import url('https://fonts.googleapis.com/css2?family=Plus+Jakarta+Sans:wght@400;500;600;700;800&family=Merriweather:ital,wght@0,300;0,400;0,700;1,300;1,400&family=Fira+Code:wght@400;600&display=swap');

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* {
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/* ================= Header & Navbar ================= */
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/* ================= Main Container ================= */
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/* ================= Hero / Book Overview Header ================= */
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/* ================= Study Mode Switcher Bar ================= */
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/* ================= Tab Content Sections ================= */
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@keyframes fadeIn {
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}

/* ================= Clean Chapter & Topic Card ================= */
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  padding: 2rem;
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body.theme-dark .flowchart-module-card:hover {
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}

.module-header {
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  padding-bottom: 1rem;
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}

/* ================= Simplified Modern Flowchart Tree ================= */
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  flex-direction: column;
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}

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  max-width: 780px;
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  padding: 1rem 1.25rem;
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  align-items: center;
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  transition: all 0.2s ease;
}

.flow-node-step:hover {
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}

.step-num-badge {
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/* Sub-branching nodes */
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}

body.theme-dark .branch-node {
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}

.branch-node h5 {
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/* High-Yield Exam Takeaway Box */
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}

.takeaway-list li {
  margin-bottom: 0.35rem;
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/* ================= In-Depth Textbook Chapter Drawer ================= */
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  border: 1px solid var(--border-color);
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  align-items: center;
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  margin-top: 1.5rem;
  font-family: inherit;
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}

.textbook-toggle-btn:hover {
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}

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  border: 1px solid var(--border-color);
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}

.textbook-drawer.open {
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}

.textbook-content p {
  margin-bottom: 1.15rem;
}

.textbook-content blockquote {
  border-left: 4px solid var(--accent-gold);
  padding: 0.65rem 1.25rem;
  margin: 1rem 0;
  background: rgba(217, 119, 6, 0.08);
  font-style: italic;
  border-radius: 0 6px 6px 0;
  color: var(--text-main);
}

/* Global View Mode Filter rules */
body.mode-flowchart-only .textbook-drawer,
body.mode-flowchart-only .textbook-toggle-btn {
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}

body.mode-textbook-only .flowchart-step-tree,
body.mode-textbook-only .branching-row {
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}

body.mode-textbook-only .textbook-drawer {
  display: block !important;
}

body.mode-textbook-only .textbook-toggle-btn {
  display: none !important;
}

/* ================= Asana & Anatomy Directory Styling ================= */
.asana-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(360px, 1fr));
  gap: 1.5rem;
  margin-top: 1.5rem;
}

.asana-card {
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  border: 1px solid var(--border-color);
  border-radius: var(--card-radius);
  padding: 1.5rem;
  box-shadow: var(--shadow-sm);
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  transition: all 0.2s ease;
}

.asana-card:hover {
  transform: translateY(-2px);
  border-color: #cbd5e1;
  box-shadow: var(--shadow-md);
}

.asana-header {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  margin-bottom: 0.75rem;
}

.asana-cat-badge {
  font-size: 0.72rem;
  text-transform: uppercase;
  font-weight: 700;
  padding: 0.2rem 0.55rem;
  border-radius: 6px;
  background: rgba(5, 150, 105, 0.1);
  color: var(--accent-emerald);
}

.anatomy-pill-row {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
  margin: 0.75rem 0;
}

.anatomy-pill {
  font-size: 0.75rem;
  background: var(--bg-primary);
  border: 1px solid var(--border-color);
  padding: 0.25rem 0.55rem;
  border-radius: 6px;
  color: var(--text-muted);
}

.view-modal-btn {
  background: #4f46e5;
  color: #ffffff;
  border: none;
  padding: 0.65rem 1rem;
  border-radius: 8px;
  font-weight: 700;
  font-size: 0.85rem;
  cursor: pointer;
  width: 100%;
  margin-top: 1rem;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  transition: all 0.2s ease;
  font-family: inherit;
}

.view-modal-btn:hover {
  background: #4338ca;
}

/* ================= Exam Bank Styling ================= */
.exam-filter-row {
  display: flex;
  gap: 0.5rem;
  margin-bottom: 1.5rem;
  flex-wrap: wrap;
}

.exam-pill-btn {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  color: var(--text-muted);
  padding: 0.45rem 0.85rem;
  border-radius: 8px;
  font-size: 0.82rem;
  font-weight: 700;
  cursor: pointer;
  transition: all 0.2s ease;
  font-family: inherit;
}

.exam-pill-btn.active {
  background: var(--accent-rose);
  color: #ffffff;
  border-color: var(--accent-rose);
}

.exam-question-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--card-radius);
  padding: 1.75rem;
  margin-bottom: 1.5rem;
  box-shadow: var(--shadow-sm);
}

.exam-q-header {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  margin-bottom: 0.75rem;
  gap: 1rem;
}

.marks-badge {
  padding: 0.25rem 0.65rem;
  border-radius: 6px;
  font-weight: 800;
  font-size: 0.78rem;
  flex-shrink: 0;
}

.marks-badge.m2 {
  background: rgba(5, 150, 105, 0.1);
  color: var(--accent-emerald);
}

.marks-badge.m16 {
  background: rgba(225, 29, 72, 0.1);
  color: var(--accent-rose);
}

.univ-tag {
  font-size: 0.78rem;
  color: var(--text-muted);
  font-weight: 600;
}

.exam-tip-alert {
  background: rgba(79, 70, 229, 0.06);
  border-left: 3px solid #6366f1;
  padding: 0.65rem 1rem;
  border-radius: 0 6px 6px 0;
  font-size: 0.85rem;
  margin: 0.75rem 0;
  color: var(--text-main);
}

.exam-toggle-answer-btn {
  background: var(--bg-primary);
  border: 1px solid var(--border-color);
  color: var(--text-main);
  padding: 0.55rem 1rem;
  border-radius: 8px;
  font-size: 0.85rem;
  font-weight: 700;
  cursor: pointer;
  margin-top: 0.75rem;
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  font-family: inherit;
  transition: all 0.2s ease;
}

.exam-toggle-answer-btn:hover {
  background: var(--bg-card-hover);
  border-color: var(--text-accent);
}

.exam-answer-drawer {
  display: none;
  margin-top: 1rem;
  padding: 1.25rem;
  background: var(--bg-primary);
  border: 1px solid var(--border-color);
  border-radius: 8px;
  animation: fadeIn 0.25s ease;
}

.exam-answer-drawer.open {
  display: block;
}

/* ================= Pranayama Breath Pacer ================= */
.pacer-container {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--card-radius);
  padding: 2.5rem;
  text-align: center;
  max-width: 600px;
  margin: 2rem auto;
  box-shadow: var(--shadow-sm);
}

.pacer-visual-wrap {
  position: relative;
  width: 220px;
  height: 220px;
  margin: 1.5rem auto;
  display: flex;
  align-items: center;
  justify-content: center;
}

.pacer-circle {
  width: 140px;
  height: 140px;
  border-radius: 50%;
  background: linear-gradient(135deg, #4f46e5, #7c3aed);
  display: flex;
  align-items: center;
  justify-content: center;
  flex-direction: column;
  color: #ffffff;
  font-weight: 800;
  transition: transform 4s ease-in-out;
  box-shadow: 0 4px 20px rgba(79, 70, 229, 0.4);
}

.pacer-status {
  font-size: 1rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.pacer-timer {
  font-size: 2rem;
  font-family: var(--font-code);
}

.pacer-controls {
  display: flex;
  justify-content: center;
  gap: 1rem;
  margin-top: 1.5rem;
}

.pacer-btn {
  background: #4f46e5;
  color: #ffffff;
  border: none;
  padding: 0.65rem 1.5rem;
  border-radius: 8px;
  font-weight: 700;
  cursor: pointer;
  font-family: inherit;
  transition: all 0.2s ease;
}

.pacer-btn:hover {
  background: #4338ca;
}

/* ================= Modal Drawer ================= */
.modal-backdrop {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: rgba(15, 23, 42, 0.75);
  backdrop-filter: blur(6px);
  z-index: 1000;
  display: none;
  align-items: center;
  justify-content: center;
  padding: 1.5rem;
}

.modal-backdrop.open {
  display: flex;
}

.modal-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: 14px;
  width: 100%;
  max-width: 800px;
  max-height: 88vh;
  overflow-y: auto;
  padding: 2rem;
  box-shadow: var(--shadow-lg);
  position: relative;
  animation: modalScale 0.2s cubic-bezier(0.16, 1, 0.3, 1);
}

@keyframes modalScale {
  from { opacity: 0; transform: scale(0.96); }
  to { opacity: 1; transform: scale(1); }
}

.close-modal-btn {
  position: absolute;
  top: 1.25rem;
  right: 1.25rem;
  background: var(--bg-primary);
  border: 1px solid var(--border-color);
  color: var(--text-main);
  width: 36px;
  height: 36px;
  border-radius: 50%;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.1rem;
  transition: all 0.2s ease;
}

.close-modal-btn:hover {
  background: var(--bg-card-hover);
}

/* ================= Mobile Bottom Navigation & Floating Top Button ================= */
.mobile-bottom-nav {
  display: none;
  position: fixed;
  bottom: 0;
  left: 0;
  right: 0;
  height: 60px;
  background: var(--bg-card);
  border-top: 1px solid var(--border-color);
  z-index: 999;
  justify-content: space-around;
  align-items: center;
  padding: 0 0.5rem;
  box-shadow: 0 -2px 10px rgba(0, 0, 0, 0.05);
}

.mobile-nav-item {
  flex: 1;
  background: transparent;
  border: none;
  color: var(--text-muted);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 2px;
  padding: 6px 0;
  cursor: pointer;
  font-family: inherit;
  font-size: 0.72rem;
  font-weight: 700;
  transition: all 0.2s ease;
  -webkit-tap-highlight-color: transparent;
}

.mobile-nav-icon {
  font-size: 1.25rem;
  line-height: 1;
}

.mobile-nav-item.active {
  color: #4f46e5;
}

body.theme-dark .mobile-nav-item.active {
  color: #818cf8;
}

/* Floating Back-To-Top Button */
.floating-top-btn {
  position: fixed;
  bottom: 75px;
  right: 1.25rem;
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background: #4f46e5;
  color: #ffffff;
  border: none;
  box-shadow: 0 4px 12px rgba(79, 70, 229, 0.4);
  font-size: 1.1rem;
  cursor: pointer;
  z-index: 900;
  display: none;
  align-items: center;
  justify-content: center;
  transition: all 0.2s ease;
  -webkit-tap-highlight-color: transparent;
}

.floating-top-btn.visible {
  display: flex;
}

/* Print Friendly Styles */
@media print {
  .app-header, .mobile-bottom-nav, .floating-top-btn, .search-filter-section, .study-mode-bar, .view-modal-btn, .theme-toggle-btn, .pacer-container, .nav-links {
    display: none !important;
  }
  body {
    background: #ffffff !important;
    color: #000000 !important;
  }
  .flowchart-module-card, .exam-question-card {
    page-break-inside: avoid;
    border: 1px solid #000000 !important;
    box-shadow: none !important;
  }
  .textbook-drawer, .exam-answer-drawer {
    display: block !important;
  }
}

/* ================= Comprehensive Mobile Optimizations ================= */
@media (max-width: 768px) {
  .desktop-nav, .desktop-only {
    display: none !important;
  }
  .mobile-bottom-nav {
    display: flex !important;
  }

  .main-layout {
    padding: 0 0.85rem 6.5rem;
    margin: 1rem auto;
  }

  .app-header {
    padding: 0.6rem 0.85rem;
  }
  .logo-text h1 {
    font-size: 1.1rem;
  }
  .logo-badge {
    width: 34px;
    height: 34px;
    font-size: 1.2rem;
  }

  .hero-banner {
    padding: 1.25rem 1rem;
    margin-bottom: 1.25rem;
  }
  .hero-title {
    font-size: 1.4rem !important;
  }

  /* Horizontal unit scroll */
  .unit-pills-wrap {
    flex-wrap: nowrap !important;
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
    scrollbar-width: none;
    padding-bottom: 4px;
  }
  .unit-pills-wrap::-webkit-scrollbar {
    display: none;
  }
  .unit-filter-btn {
    flex-shrink: 0;
  }

  /* Cards */
  .flowchart-module-card, .exam-question-card {
    padding: 1.25rem 1rem !important;
    margin-bottom: 1.25rem;
  }

  .module-title-box h3 {
    font-size: 1.2rem;
  }

  .flow-node-step {
    padding: 0.75rem 0.85rem !important;
    gap: 0.65rem !important;
  }
  .step-num-badge {
    width: 28px !important;
    height: 28px !important;
    font-size: 0.8rem !important;
  }

  .branching-row {
    flex-direction: column;
    gap: 0.5rem;
  }
  .branch-node {
    min-width: 100% !important;
  }

  .asana-grid {
    grid-template-columns: 1fr !important;
  }

  /* Modal Bottom Sheet */
  .modal-backdrop {
    padding: 0;
    align-items: flex-end;
  }
  .modal-card {
    border-radius: 18px 18px 0 0 !important;
    padding: 1.25rem 1rem 3rem !important;
    max-height: 92vh !important;
  }
  .modal-card [style*="grid-template-columns: 1fr 1fr"] {
    grid-template-columns: 1fr !important;
  }

  .study-mode-bar {
    padding: 0.65rem 0.85rem;
  }
  .mode-toggle-group {
    width: 100%;
  }
  .expand-all-btn {
    width: 100%;
    text-align: center;
  }
}