/* CHEMMANTRA ALCOHOLS MASTER PRESENTATION STYLESHEET — Light-First Edition */
:root {
  --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  --font-mono: 'JetBrains Mono', 'Fira Code', Consolas, Monaco, monospace;
  --font-serif: 'Cormorant Garamond', Georgia, serif;
  
  /* Light Theme (Default) — clean white with vivid accents */
  --bg-primary: #f7f8fc;
  --bg-secondary: #ffffff;
  --bg-card: #ffffff;
  --bg-hover: #eef2f7;
  --border-color: rgba(0, 0, 0, 0.08);
  --border-focus: #0369a1;
  
  --text-primary: #1e293b;
  --text-secondary: #475569;
  --text-muted: #64748b;
  
  --accent-cyan: #0284c7;
  --accent-emerald: #059669;
  --accent-amber: #d97706;
  --accent-rose: #e11d48;
  --accent-purple: #7c3aed;
  --accent-blue: #2563eb;

  --shadow-card: 0 4px 24px -4px rgba(0, 0, 0, 0.08), 0 2px 8px -2px rgba(0, 0, 0, 0.04);
  --shadow-glow: 0 0 18px rgba(2, 132, 199, 0.12);
  --radius-sm: 6px;
  --radius-md: 10px;
  --radius-lg: 16px;
}

[data-theme="dark"] {
  --bg-primary: #0a0f1d;
  --bg-secondary: #0f172a;
  --bg-card: #131d35;
  --bg-hover: #1e293b;
  --border-color: rgba(255, 255, 255, 0.1);
  --border-focus: #38bdf8;
  
  --text-primary: #f8fafc;
  --text-secondary: #94a3b8;
  --text-muted: #64748b;
  
  --accent-cyan: #38bdf8;
  --accent-emerald: #34d399;
  --accent-amber: #fbbf24;
  --accent-rose: #f43f5e;
  --accent-purple: #a78bfa;
  --accent-blue: #60a5fa;

  --shadow-card: 0 10px 25px -5px rgba(0, 0, 0, 0.5), 0 8px 10px -6px rgba(0, 0, 0, 0.4);
  --shadow-glow: 0 0 20px rgba(56, 189, 248, 0.25);
}

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

body {
  font-family: var(--font-sans);
  background-color: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.6;
  overflow-x: hidden;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

/* TOP NAVBAR */
.top-nav {
  height: 60px;
  background: var(--bg-secondary);
  border-bottom: 1px solid var(--border-color);
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 1.5rem;
  position: sticky;
  top: 0;
  z-index: 1000;
}

.brand {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  font-weight: 700;
  font-size: 1.1rem;
  letter-spacing: -0.02em;
}

.brand-badge {
  background: linear-gradient(135deg, #38bdf8, #6366f1);
  color: #fff;
  padding: 0.25rem 0.6rem;
  border-radius: var(--radius-sm);
  font-size: 0.8rem;
  font-weight: 800;
  letter-spacing: 0.05em;
  text-transform: uppercase;
}

.nav-controls {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.btn {
  background: var(--bg-card);
  color: var(--text-primary);
  border: 1px solid var(--border-color);
  padding: 0.4rem 0.8rem;
  border-radius: var(--radius-sm);
  font-size: 0.875rem;
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  font-weight: 500;
  transition: all 0.2s ease;
  user-select: none;
}

.btn:hover {
  background: var(--bg-hover);
  border-color: var(--border-focus);
}

.btn-primary {
  background: var(--accent-cyan);
  color: #0f172a;
  border: none;
  font-weight: 600;
}

.btn-primary:hover {
  filter: brightness(1.1);
}

.btn.active {
  background: var(--accent-cyan);
  color: #0f172a;
  border-color: var(--accent-cyan);
}

.slide-counter-wrapper {
  display: flex;
  align-items: center;
  gap: 0.4rem;
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--text-secondary);
}

.slide-input {
  width: 50px;
  padding: 0.3rem 0.4rem;
  text-align: center;
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  color: var(--text-primary);
  border-radius: var(--radius-sm);
  font-weight: 700;
  font-size: 0.9rem;
}

.slide-input:focus {
  outline: none;
  border-color: var(--accent-cyan);
}

/* PROGRESS BAR */
.progress-bar-container {
  height: 3px;
  background: rgba(255, 255, 255, 0.05);
  position: relative;
  width: 100%;
}

.progress-bar {
  height: 100%;
  background: linear-gradient(90deg, var(--accent-cyan), var(--accent-emerald));
  width: 0%;
  transition: width 0.25s ease;
}

/* MAIN PRESENTATION STAGE */
.presentation-stage {
  flex: 1;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 1.5rem;
  position: relative;
}

/* SLIDE CARD */
.slide-card {
  width: 100%;
  max-width: 1300px;
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-card);
  display: flex;
  flex-direction: column;
  height: calc(100vh - 150px);
  min-height: 580px;
  overflow: hidden;
  transition: transform 0.3s ease, opacity 0.3s ease;
}

.slide-header {
  padding: 1.25rem 2rem;
  background: var(--bg-secondary);
  border-bottom: 1px solid var(--border-color);
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: 1rem;
}

.slide-title-area h2 {
  font-size: 1.45rem;
  font-weight: 700;
  color: var(--text-primary);
  letter-spacing: -0.01em;
  line-height: 1.3;
}

.slide-subtitle {
  font-size: 0.9rem;
  color: var(--text-muted);
  margin-top: 0.2rem;
}

.slide-meta-badges {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  flex-shrink: 0;
}

.badge {
  padding: 0.25rem 0.6rem;
  border-radius: 999px;
  font-size: 0.75rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  background: rgba(56, 189, 248, 0.15);
  color: var(--accent-cyan);
  border: 1px solid rgba(56, 189, 248, 0.25);
}

.slide-body {
  flex: 1;
  padding: 2rem 2.5rem;
  overflow-y: auto;
  font-size: 1.05rem;
  line-height: 1.7;
}

/* TYPOGRAPHY & CODE */
.slide-body h1 {
  font-size: 1.6rem;
  margin-bottom: 1rem;
  color: var(--accent-cyan);
  border-bottom: 1px solid var(--border-color);
  padding-bottom: 0.4rem;
}

.slide-body h2 {
  font-size: 1.3rem;
  margin-top: 1.2rem;
  margin-bottom: 0.6rem;
  color: var(--accent-emerald);
}

.slide-body h3 {
  font-size: 1.15rem;
  margin-top: 1rem;
  margin-bottom: 0.5rem;
  color: var(--accent-amber);
}

.slide-body p {
  margin-bottom: 1rem;
  color: var(--text-primary);
}

.slide-body strong {
  color: #fff;
  font-weight: 700;
}
[data-theme="light"] .slide-body strong {
  color: #0f172a;
}

.slide-body ul, .slide-body ol {
  margin-bottom: 1.2rem;
  padding-left: 1.8rem;
}

.slide-body li {
  margin-bottom: 0.4rem;
}

.slide-body code {
  font-family: var(--font-mono);
  background: rgba(255, 255, 255, 0.08);
  padding: 0.15rem 0.4rem;
  border-radius: var(--radius-sm);
  font-size: 0.9em;
  color: var(--accent-amber);
}

.slide-body pre {
  background: #060a14;
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 1rem 1.25rem;
  margin-bottom: 1.2rem;
  overflow-x: auto;
}

.slide-body pre code {
  background: transparent;
  padding: 0;
  color: #e2e8f0;
  font-size: 0.95rem;
  line-height: 1.5;
}

/* TABLES */
.slide-body table {
  width: 100%;
  border-collapse: collapse;
  margin: 1.2rem 0;
  background: var(--bg-secondary);
  border-radius: var(--radius-md);
  overflow: hidden;
  border: 1px solid var(--border-color);
  font-size: 0.95rem;
}

.slide-body th, .slide-body td {
  padding: 0.75rem 1rem;
  text-align: left;
  border-bottom: 1px solid var(--border-color);
}

.slide-body th {
  background: #0f172a;
  color: var(--accent-cyan);
  font-weight: 700;
  text-transform: uppercase;
  font-size: 0.8rem;
  letter-spacing: 0.05em;
}
[data-theme="light"] .slide-body th {
  background: #e2e8f0;
  color: #0284c7;
}

.slide-body tr:hover td {
  background: var(--bg-hover);
}

/* CALLOUTS */
.callout {
  border-radius: var(--radius-md);
  padding: 1rem 1.25rem;
  margin: 1.2rem 0;
  border-left: 4px solid;
  background: var(--bg-secondary);
}

.callout-title {
  font-weight: 700;
  font-size: 0.85rem;
  letter-spacing: 0.05em;
  margin-bottom: 0.4rem;
  display: flex;
  align-items: center;
  gap: 0.4rem;
}

.callout-note {
  border-left-color: var(--accent-blue);
  background: rgba(96, 165, 250, 0.08);
}
.callout-note .callout-title { color: var(--accent-blue); }

.callout-tip {
  border-left-color: var(--accent-emerald);
  background: rgba(52, 211, 153, 0.08);
}
.callout-tip .callout-title { color: var(--accent-emerald); }

.callout-important {
  border-left-color: var(--accent-purple);
  background: rgba(167, 139, 250, 0.08);
}
.callout-important .callout-title { color: var(--accent-purple); }

.callout-warning {
  border-left-color: var(--accent-amber);
  background: rgba(251, 191, 36, 0.08);
}
.callout-warning .callout-title { color: var(--accent-amber); }

.callout-caution {
  border-left-color: var(--accent-rose);
  background: rgba(244, 63, 94, 0.08);
}
.callout-caution .callout-title { color: var(--accent-rose); }

/* BOTTOM STATUS BAR */
.bottom-bar {
  height: 44px;
  background: var(--bg-secondary);
  border-top: 1px solid var(--border-color);
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 1.5rem;
  font-size: 0.82rem;
  color: var(--text-muted);
}

.bottom-left {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.bottom-right {
  display: flex;
  align-items: center;
  gap: 1.25rem;
}

/* DRAWER / SIDEBAR (MODULES) */
.drawer-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.6);
  backdrop-filter: blur(4px);
  z-index: 2000;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.25s ease;
}

.drawer-overlay.open {
  opacity: 1;
  pointer-events: auto;
}

.drawer {
  position: fixed;
  top: 0;
  right: 0;
  bottom: 0;
  width: 420px;
  max-width: 90vw;
  background: var(--bg-secondary);
  border-left: 1px solid var(--border-color);
  box-shadow: -10px 0 30px rgba(0, 0, 0, 0.5);
  z-index: 2001;
  transform: translateX(100%);
  transition: transform 0.3s cubic-bezier(0.16, 1, 0.3, 1);
  display: flex;
  flex-direction: column;
}

.drawer.open {
  transform: translateX(0);
}

.drawer-header {
  padding: 1.25rem 1.5rem;
  border-bottom: 1px solid var(--border-color);
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.drawer-header h3 {
  font-size: 1.1rem;
  color: var(--text-primary);
}

.drawer-search {
  padding: 0.75rem 1.5rem;
  border-bottom: 1px solid var(--border-color);
}

.drawer-search input {
  width: 100%;
  padding: 0.5rem 0.8rem;
  border-radius: var(--radius-sm);
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  color: var(--text-primary);
  font-size: 0.875rem;
}

.drawer-search input:focus {
  outline: none;
  border-color: var(--accent-cyan);
}

.drawer-content {
  flex: 1;
  overflow-y: auto;
  padding: 1rem 0;
}

.drawer-module-group {
  margin-bottom: 1.5rem;
}

.drawer-module-title {
  padding: 0.4rem 1.5rem;
  font-size: 0.8rem;
  font-weight: 700;
  color: var(--accent-cyan);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.drawer-slide-item {
  padding: 0.6rem 1.5rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  cursor: pointer;
  font-size: 0.875rem;
  color: var(--text-secondary);
  transition: all 0.15s ease;
  border-left: 3px solid transparent;
}

.drawer-slide-item:hover {
  background: var(--bg-hover);
  color: var(--text-primary);
}

.drawer-slide-item.active {
  background: rgba(56, 189, 248, 0.1);
  color: var(--accent-cyan);
  border-left-color: var(--accent-cyan);
  font-weight: 600;
}

/* SEARCH MODAL */
.modal-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.75);
  backdrop-filter: blur(5px);
  z-index: 3000;
  display: flex;
  align-items: flex-start;
  justify-content: center;
  padding-top: 10vh;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.2s ease;
}

.modal-overlay.open {
  opacity: 1;
  pointer-events: auto;
}

.modal-card {
  width: 650px;
  max-width: 90vw;
  background: var(--bg-secondary);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-card);
  overflow: hidden;
  display: flex;
  flex-direction: column;
  max-height: 75vh;
}

.modal-search-box {
  padding: 1rem 1.25rem;
  border-bottom: 1px solid var(--border-color);
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.modal-search-box input {
  flex: 1;
  background: transparent;
  border: none;
  font-size: 1.1rem;
  color: var(--text-primary);
}

.modal-search-box input:focus {
  outline: none;
}

.modal-results {
  flex: 1;
  overflow-y: auto;
  padding: 0.75rem;
}

.modal-result-item {
  padding: 0.75rem 1rem;
  border-radius: var(--radius-sm);
  cursor: pointer;
  border: 1px solid transparent;
  margin-bottom: 0.4rem;
}

.modal-result-item:hover {
  background: var(--bg-hover);
  border-color: var(--border-color);
}

.result-title {
  font-weight: 600;
  color: var(--accent-cyan);
  margin-bottom: 0.2rem;
  font-size: 0.95rem;
}

.result-snippet {
  font-size: 0.85rem;
  color: var(--text-muted);
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

/* CONTINUOUS DOCUMENT MODE (BOOK VIEW) */
.book-mode-container {
  max-width: 1000px;
  margin: 2rem auto;
  padding: 0 1.5rem;
  display: flex;
  flex-direction: column;
  gap: 2.5rem;
}

.book-slide-item {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-card);
  overflow: hidden;
}

/* CUSTOM SCROLLBAR */
::-webkit-scrollbar {
  width: 8px;
  height: 8px;
}
::-webkit-scrollbar-track {
  background: rgba(0, 0, 0, 0.1);
}
::-webkit-scrollbar-thumb {
  background: rgba(255, 255, 255, 0.15);
  border-radius: 4px;
}
::-webkit-scrollbar-thumb:hover {
  background: rgba(255, 255, 255, 0.25);
}


/* M. S. Chouhan Question Image Embed Styling */
.q-image-box {
  margin: 0.5rem auto 1.5rem auto;
  text-align: center;
  background: #ffffff;
  border-radius: 12px;
  padding: 14px 18px;
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.22);
  border: 1px solid rgba(255, 255, 255, 0.15);
  max-width: 96%;
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 16px;
  flex-wrap: wrap;
}

.q-image-box img {
  max-width: 100%;
  max-height: 400px;
  height: auto;
  object-fit: contain;
  border-radius: 6px;
  transition: transform 0.2s ease, box-shadow 0.2s ease;
  display: block;
  cursor: zoom-in;
}

.q-image-box img:hover {
  transform: scale(1.02);
}

@media (max-width: 768px) {
  .q-image-box img {
    max-height: 280px;
  }
}

/* ==========================================================================
   ChemMantra 2D Mechanism Video & High-Res Poster Showcase
   ========================================================================== */
.mechanism-video-card {
  margin: 1.5rem 0;
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-card);
  transition: border-color 0.3s ease, box-shadow 0.3s ease;
}

.mechanism-video-card:hover {
  border-color: var(--accent-cyan);
  box-shadow: var(--shadow-glow);
}

.mechanism-video-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0.75rem 1.25rem;
  background: rgba(56, 189, 248, 0.08);
  border-bottom: 1px solid var(--border-color);
  font-family: var(--font-sans);
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--accent-cyan);
}

.mechanism-video-badge {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  background: rgba(56, 189, 248, 0.15);
  padding: 2px 8px;
  border-radius: 999px;
  font-size: 0.75rem;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  color: var(--accent-cyan);
}

.mechanism-video-body {
  padding: 1rem;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.75rem;
  background: #050811;
}

.mechanism-video-player {
  width: 100%;
  max-width: 960px;
  max-height: 520px;
  aspect-ratio: 16 / 9;
  border-radius: var(--radius-md);
  outline: none;
  background: #000;
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.6);
}

.mechanism-video-actions {
  display: flex;
  align-items: center;
  justify-content: flex-end;
  gap: 12px;
  width: 100%;
  padding: 0.5rem 1rem 0.75rem 1rem;
  background: var(--bg-card);
  border-top: 1px solid var(--border-color);
  font-size: 0.85rem;
}

.mechanism-video-actions a {
  color: var(--accent-emerald);
  text-decoration: none;
  font-weight: 500;
  display: inline-flex;
  align-items: center;
  gap: 4px;
}

.mechanism-video-actions a:hover {
  text-decoration: underline;
}


/* =========================================================
   LIGHT-THEME ENHANCEMENTS & CARD COLORFUL POLISH
   ========================================================= */

/* Top-border accents for cards to make content vibrant in light mode */
.card, .summary-card, .mechanism-step {
  border-top: 3px solid var(--accent-cyan);
}
.grid .card:nth-child(1), .card:nth-of-type(1) { border-top-color: #0284c7; }
.grid .card:nth-child(2), .card:nth-of-type(2) { border-top-color: #059669; }
.grid .card:nth-child(3), .card:nth-of-type(3) { border-top-color: #d97706; }
.grid .card:nth-child(4), .card:nth-of-type(4) { border-top-color: #7c3aed; }
.grid .card:nth-child(5), .card:nth-of-type(5) { border-top-color: #e11d48; }
.grid .card:nth-child(6), .card:nth-of-type(6) { border-top-color: #0891b2; }

/* Callout boxes with vibrant borders & soft light fills */
.callout, .alert, .note, .tip, .warning, .key-rule {
  border-left-width: 4px !important;
  border-radius: var(--radius-sm);
  padding: 1rem 1.25rem;
  margin: 1rem 0;
}
.callout-info, .tip {
  background: #f0fdf4 !important;
  border-left-color: #059669 !important;
  color: #064e3b !important;
}
.callout-warning, .warning {
  background: #fffbeb !important;
  border-left-color: #d97706 !important;
  color: #78350f !important;
}
.callout-danger, .error, .danger {
  background: #fff1f2 !important;
  border-left-color: #e11d48 !important;
  color: #881337 !important;
}
.callout-purple {
  background: #faf5ff !important;
  border-left-color: #7c3aed !important;
  color: #4c1d95 !important;
}

[data-theme="dark"] .callout-info, [data-theme="dark"] .tip {
  background: rgba(5, 150, 105, 0.15) !important;
  color: #a7f3d0 !important;
}
[data-theme="dark"] .callout-warning, [data-theme="dark"] .warning {
  background: rgba(217, 119, 6, 0.15) !important;
  color: #fde68a !important;
}
[data-theme="dark"] .callout-danger, [data-theme="dark"] .danger {
  background: rgba(225, 29, 72, 0.15) !important;
  color: #fecdd3 !important;
}

/* Pre / Code blocks in light mode */
pre {
  background: #f8fafc !important;
  border: 1px solid rgba(0, 0, 0, 0.08) !important;
  color: #0f172a !important;
  border-radius: var(--radius-md);
  padding: 1rem;
}

[data-theme="dark"] pre {
  background: #0b1120 !important;
  border-color: rgba(255, 255, 255, 0.1) !important;
  color: #f8fafc !important;
}

code {
  font-family: var(--font-mono);
  font-size: 0.9em;
  padding: 0.2em 0.4em;
  border-radius: 4px;
  background: rgba(2, 132, 199, 0.08);
  color: #0369a1;
}

[data-theme="dark"] code {
  background: rgba(56, 189, 248, 0.12);
  color: #38bdf8;
}

pre code {
  background: transparent !important;
  color: inherit !important;
  padding: 0 !important;
}

/* Subtle page background pattern for light mode */
body {
  background-image: radial-gradient(circle at 25px 25px, rgba(0,0,0,0.015) 1px, transparent 0);
  background-size: 50px 50px;
}

[data-theme="dark"] body {
  background-image: none;
}

/* Slide Header in Light Mode */
.slide-header {
  background: linear-gradient(135deg, #f0f7ff 0%, #faf5ff 50%, #f0fdf4 100%);
  border-bottom: 1px solid var(--border-color);
}

[data-theme="dark"] .slide-header {
  background: rgba(15, 23, 42, 0.6);
}

/* Light mode table styling */
table {
  background: var(--bg-card);
  border-collapse: collapse;
}

table th {
  background: rgba(2, 132, 199, 0.08);
  color: var(--accent-cyan);
  font-weight: 700;
  border-bottom: 2px solid var(--border-color);
}

[data-theme="dark"] table th {
  background: rgba(56, 189, 248, 0.12);
}

table td {
  border-bottom: 1px solid var(--border-color);
}

table tr:nth-child(even) td {
  background: rgba(0, 0, 0, 0.02);
}

[data-theme="dark"] table tr:nth-child(even) td {
  background: rgba(255, 255, 255, 0.02);
}