/* ===================================
   AI Summit Explorer — Style System
   IndiaAI Impact Summit 2026
   =================================== */

/* --- CSS Custom Properties --- */
:root {
  /* Base palette — warm beige / light */
  --bg-primary: #f5f0e8;
  --bg-secondary: #faf7f2;
  --bg-tertiary: #ede8df;
  --bg-card: #ffffff;
  --bg-card-hover: #f2ede4;
  --bg-glass: rgba(250, 247, 242, 0.85);
  --bg-overlay: rgba(0, 0, 0, 0.45);

  /* Text */
  --text-primary: #1a1a1a;
  --text-secondary: #4a4a4a;
  --text-tertiary: #787878;
  --text-muted: #9e9e9e;

  /* Accents */
  --accent-primary: #c0392b;
  --accent-secondary: #2980b9;
  --accent-gradient: linear-gradient(135deg, #c0392b 0%, #e74c3c 100%);
  --accent-glow: 0 0 20px rgba(192, 57, 43, 0.1);
  --accent-gradient-text: linear-gradient(135deg, #c0392b, #e74c3c);

  /* Category colors */
  --cat-keynotes: #e67e22;
  --cat-governance: #8e44ad;
  --cat-infrastructure: #2980b9;
  --cat-sectoral: #27ae60;
  --cat-social: #e74c3c;
  --cat-safety: #c0392b;
  --cat-future: #2c3e50;

  /* Borders */
  --border-primary: rgba(0, 0, 0, 0.08);
  --border-hover: rgba(0, 0, 0, 0.15);

  /* Spacing */
  --header-height: 64px;
  --sidebar-width: 300px;
  --chat-width: 400px;

  /* Transitions */
  --ease-out: cubic-bezier(0.16, 1, 0.3, 1);
  --transition-fast: 150ms var(--ease-out);
  --transition-med: 250ms var(--ease-out);
  --transition-slow: 400ms var(--ease-out);

  /* Radius */
  --radius-sm: 6px;
  --radius-md: 10px;
  --radius-lg: 14px;
  --radius-xl: 20px;
}

/* --- Reset & Base --- */
*, *::before, *::after {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  font-size: 15px;
  scroll-behavior: smooth;
}

body {
  font-family: "Inter", -apple-system, BlinkMacSystemFont, sans-serif;
  background: var(--bg-primary);
  color: var(--text-primary);
  overflow: hidden;
  height: 100vh;
  -webkit-font-smoothing: antialiased;
}

/* Scrollbar styling */
::-webkit-scrollbar { width: 6px; height: 6px; }
::-webkit-scrollbar-track { background: transparent; }
::-webkit-scrollbar-thumb {
  background: rgba(0, 0, 0, 0.15);
  border-radius: 10px;
}
::-webkit-scrollbar-thumb:hover { background: rgba(0, 0, 0, 0.25); }

/* --- Header --- */
.header {
  height: var(--header-height);
  background: var(--bg-glass);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--border-primary);
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 24px;
  position: sticky;
  top: 0;
  z-index: 100;
}

.header-left { display: flex; align-items: center; }

.logo {
  display: flex;
  align-items: center;
  gap: 12px;
}

.logo-icon {
  font-size: 28px;
  filter: drop-shadow(0 0 8px rgba(255,153,51,0.3));
}

.logo-text h1 {
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--accent-primary);
  line-height: 1.2;
}

.logo-subtitle {
  font-size: 0.7rem;
  color: var(--text-tertiary);
  font-weight: 500;
  letter-spacing: 0.5px;
  text-transform: uppercase;
}

.header-center {
  flex: 1;
  max-width: 500px;
  margin: 0 32px;
}

.search-box {
  position: relative;
  display: flex;
  align-items: center;
  background: var(--bg-tertiary);
  border: 1px solid var(--border-primary);
  border-radius: var(--radius-lg);
  padding: 0 16px;
  transition: all var(--transition-med);
}

.search-box:focus-within {
  border-color: var(--accent-primary);
  box-shadow: var(--accent-glow);
}

.search-icon {
  color: var(--text-tertiary);
  font-size: 20px;
  margin-right: 8px;
}

.search-box input {
  background: transparent;
  border: none;
  outline: none;
  color: var(--text-primary);
  font-size: 0.9rem;
  font-family: inherit;
  width: 100%;
  padding: 10px 0;
}

.search-box input::placeholder { color: var(--text-muted); }

.search-shortcut {
  background: var(--bg-secondary);
  color: var(--text-muted);
  font-size: 0.7rem;
  padding: 3px 6px;
  border-radius: 4px;
  border: 1px solid var(--border-primary);
  font-family: inherit;
  white-space: nowrap;
}

.header-right {
  display: flex;
  align-items: center;
  gap: 20px;
}

.stats {
  display: flex;
  gap: 20px;
}

.stat {
  display: flex;
  flex-direction: column;
  align-items: center;
}

.stat-number {
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--accent-primary);
}

.stat-label {
  font-size: 0.65rem;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

.chat-toggle-btn {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 8px 16px;
  background: var(--accent-gradient);
  border: none;
  border-radius: var(--radius-md);
  color: #ffffff;
  font-weight: 600;
  font-size: 0.85rem;
  cursor: pointer;
  transition: all var(--transition-med);
  font-family: inherit;
}

.chat-toggle-btn:hover {
  transform: translateY(-1px);
  box-shadow: 0 4px 20px rgba(192, 57, 43, 0.25);
}

.chat-toggle-btn .material-icons-round { font-size: 18px; }

/* --- App Layout --- */
.app-layout {
  display: flex;
  height: calc(100vh - var(--header-height));
  overflow: hidden;
}

/* --- Sidebar --- */
.sidebar {
  width: var(--sidebar-width);
  min-width: var(--sidebar-width);
  background: var(--bg-secondary);
  border-right: 1px solid var(--border-primary);
  display: flex;
  flex-direction: column;
  transition: all var(--transition-slow);
  overflow: hidden;
}

.sidebar.collapsed {
  width: 0;
  min-width: 0;
  padding: 0;
  border-right: none;
}

.sidebar-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 16px 20px;
  border-bottom: 1px solid var(--border-primary);
}

.sidebar-header h2 {
  font-size: 0.8rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 1px;
  color: var(--text-tertiary);
}

.sidebar-collapse-btn {
  background: none;
  border: none;
  color: var(--text-tertiary);
  cursor: pointer;
  padding: 4px;
  border-radius: var(--radius-sm);
  transition: all var(--transition-fast);
}

.sidebar-collapse-btn:hover {
  color: var(--text-primary);
  background: var(--bg-tertiary);
}

.category-tree {
  flex: 1;
  overflow-y: auto;
  padding: 8px 0;
}

.category-group {
  margin-bottom: 2px;
}

.category-header {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 10px 20px;
  cursor: pointer;
  transition: all var(--transition-fast);
  border-left: 3px solid transparent;
  user-select: none;
}

.category-header:hover {
  background: var(--bg-tertiary);
}

.category-header.active {
  background: var(--bg-tertiary);
}

.category-icon {
  font-size: 20px;
  width: 28px;
  text-align: center;
  flex-shrink: 0;
}

.category-name {
  flex: 1;
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--text-primary);
}

.category-count {
  font-size: 0.7rem;
  font-weight: 600;
  color: var(--text-muted);
  background: var(--bg-primary);
  padding: 2px 8px;
  border-radius: 10px;
  min-width: 28px;
  text-align: center;
}

.category-expand {
  color: var(--text-muted);
  font-size: 18px;
  transition: transform var(--transition-fast);
}

.category-group.expanded .category-expand {
  transform: rotate(180deg);
}

.subcategory-list {
  max-height: 0;
  overflow: hidden;
  transition: max-height var(--transition-slow);
}

.category-group.expanded .subcategory-list {
  max-height: 500px;
}

.subcategory-item {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 8px 20px 8px 56px;
  cursor: pointer;
  transition: all var(--transition-fast);
  font-size: 0.8rem;
  color: var(--text-secondary);
}

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

.subcategory-item.active {
  color: var(--accent-primary);
  background: rgba(6, 214, 160, 0.05);
}

.subcategory-dot {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  flex-shrink: 0;
}

.subcategory-name { flex: 1; }

.subcategory-count {
  font-size: 0.65rem;
  color: var(--text-muted);
}

.sidebar-footer {
  padding: 12px 16px;
  border-top: 1px solid var(--border-primary);
}

.show-all-btn {
  display: flex;
  align-items: center;
  gap: 8px;
  width: 100%;
  padding: 10px 16px;
  background: var(--bg-tertiary);
  border: 1px solid var(--border-primary);
  border-radius: var(--radius-md);
  color: var(--text-secondary);
  font-size: 0.82rem;
  font-weight: 500;
  cursor: pointer;
  transition: all var(--transition-fast);
  font-family: inherit;
}

.show-all-btn:hover {
  background: var(--bg-card-hover);
  color: var(--text-primary);
  border-color: var(--border-hover);
}

.show-all-btn .material-icons-round { font-size: 18px; }

/* --- Favorites Section --- */
.favorites-section {
  border-top: 1px solid var(--border-primary);
  padding: 0;
}

.favorites-header {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 12px 20px 8px;
}

.favorites-header h3 {
  font-size: 0.8rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 1px;
  color: var(--text-tertiary);
  flex: 1;
}

.favorites-count {
  font-size: 0.65rem;
  font-weight: 600;
  color: var(--text-muted);
  background: var(--bg-primary);
  padding: 2px 8px;
  border-radius: 10px;
  min-width: 20px;
  text-align: center;
}

.favorites-list {
  padding: 0 12px 12px;
  max-height: 220px;
  overflow-y: auto;
}

.favorites-empty {
  font-size: 0.75rem;
  color: var(--text-muted);
  padding: 8px 8px;
  line-height: 1.5;
}

.favorite-item {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 8px;
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: all var(--transition-fast);
}

.favorite-item:hover {
  background: var(--bg-tertiary);
}

.favorite-thumb {
  width: 48px;
  height: 28px;
  object-fit: cover;
  border-radius: 4px;
  flex-shrink: 0;
}

.favorite-info {
  flex: 1;
  min-width: 0;
}

.favorite-title {
  display: block;
  font-size: 0.75rem;
  font-weight: 500;
  color: var(--text-primary);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.favorite-meta {
  font-size: 0.65rem;
  color: var(--text-muted);
}

.favorite-remove {
  background: none;
  border: none;
  color: var(--text-muted);
  cursor: pointer;
  padding: 2px;
  border-radius: 4px;
  display: flex;
  opacity: 0;
  transition: all var(--transition-fast);
  flex-shrink: 0;
}

.favorite-item:hover .favorite-remove { opacity: 1; }

.favorite-remove:hover {
  color: var(--cat-safety);
  background: rgba(239, 68, 68, 0.1);
}

.favorite-remove .material-icons-round { font-size: 16px; }

/* --- Card Favorite Button --- */
.card-fav-btn {
  position: absolute;
  top: 8px;
  left: 8px;
  background: rgba(0, 0, 0, 0.6);
  border: none;
  color: var(--text-secondary);
  width: 32px;
  height: 32px;
  border-radius: 6px;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  z-index: 2;
  opacity: 0;
  transition: all var(--transition-fast);
}

.video-card:hover .card-fav-btn { opacity: 1; }

.card-fav-btn.active {
  opacity: 1;
  color: var(--accent-primary);
  background: rgba(6, 214, 160, 0.2);
}

.card-fav-btn:hover {
  color: var(--accent-primary);
  background: rgba(6, 214, 160, 0.3);
  transform: scale(1.1);
}

.card-fav-btn .material-icons-round { font-size: 18px; }

/* --- Main Content --- */
.main-content {
  flex: 1;
  overflow-y: auto;
  display: flex;
  flex-direction: column;
}

.filter-bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 14px 28px;
  background: var(--bg-secondary);
  border-bottom: 1px solid var(--border-primary);
  position: sticky;
  top: 0;
  z-index: 10;
}

.breadcrumb {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 0.85rem;
}

.breadcrumb-item {
  color: var(--text-tertiary);
  cursor: pointer;
  transition: color var(--transition-fast);
}

.breadcrumb-item:hover { color: var(--text-primary); }

.breadcrumb-item.active {
  color: var(--text-primary);
  font-weight: 600;
}

.breadcrumb-separator {
  color: var(--text-muted);
  font-size: 0.8rem;
}

.filter-actions {
  display: flex;
  align-items: center;
  gap: 16px;
}

.results-count {
  font-size: 0.8rem;
  color: var(--text-tertiary);
}

.view-toggle {
  display: flex;
  background: var(--bg-tertiary);
  border-radius: var(--radius-sm);
  overflow: hidden;
  border: 1px solid var(--border-primary);
}

.view-btn {
  background: none;
  border: none;
  color: var(--text-muted);
  padding: 6px 10px;
  cursor: pointer;
  transition: all var(--transition-fast);
  display: flex;
  align-items: center;
}

.view-btn .material-icons-round { font-size: 18px; }

.view-btn.active {
  background: var(--bg-card-hover);
  color: var(--accent-primary);
}

.view-btn:hover:not(.active) { color: var(--text-secondary); }

/* --- Video Grid --- */
.video-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
  gap: 20px;
  padding: 24px 28px;
  flex: 1;
}

.video-grid.list-view {
  grid-template-columns: 1fr;
  gap: 8px;
}

/* --- Video Card --- */
.video-card {
  background: var(--bg-card);
  border: 1px solid var(--border-primary);
  border-radius: var(--radius-lg);
  overflow: hidden;
  transition: all var(--transition-med);
  cursor: pointer;
  position: relative;
}

.video-card:hover {
  transform: translateY(-4px);
  border-color: var(--border-hover);
  box-shadow: 0 12px 40px rgba(0, 0, 0, 0.1);
}

.video-card::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: var(--card-accent-color, var(--accent-gradient));
  opacity: 0;
  transition: opacity var(--transition-med);
}

.video-card:hover::before { opacity: 1; }

.card-thumbnail {
  position: relative;
  aspect-ratio: 16 / 9;
  overflow: hidden;
  background: var(--bg-tertiary);
}

.card-thumbnail img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform var(--transition-slow);
}

.video-card:hover .card-thumbnail img {
  transform: scale(1.05);
}

.card-duration {
  position: absolute;
  bottom: 8px;
  right: 8px;
  background: rgba(0, 0, 0, 0.85);
  color: white;
  font-size: 0.72rem;
  font-weight: 600;
  padding: 3px 8px;
  border-radius: 4px;
  letter-spacing: 0.5px;
}

.card-play-overlay {
  position: absolute;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  background: rgba(0, 0, 0, 0.35);
  opacity: 0;
  transition: opacity var(--transition-med);
}

.video-card:hover .card-play-overlay { opacity: 1; }

.card-play-btn {
  width: 56px;
  height: 56px;
  border-radius: 50%;
  background: var(--accent-gradient);
  display: flex;
  align-items: center;
  justify-content: center;
  transform: scale(0.8);
  transition: transform var(--transition-med);
}

.video-card:hover .card-play-btn { transform: scale(1); }

.card-play-btn .material-icons-round {
  font-size: 28px;
  color: #ffffff;
  margin-left: 2px;
}

.card-transcript-badge {
  position: absolute;
  top: 8px;
  right: 8px;
  background: rgba(192, 57, 43, 0.9);
  color: #ffffff;
  width: 28px;
  height: 28px;
  border-radius: 6px;
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 2;
  box-shadow: 0 2px 8px rgba(0,0,0,0.15);
}

.card-transcript-badge .material-icons-round {
  font-size: 16px;
}

.card-body {
  padding: 16px;
}

.card-category-badge {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  font-size: 0.68rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.5px;
  padding: 3px 10px;
  border-radius: 20px;
  margin-bottom: 10px;
}

.card-title {
  font-size: 0.92rem;
  font-weight: 600;
  color: var(--text-primary);
  line-height: 1.45;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
  margin-bottom: 10px;
}

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

.card-subcategory {
  font-size: 0.72rem;
  color: var(--text-tertiary);
}

.card-link {
  display: flex;
  align-items: center;
  gap: 4px;
  font-size: 0.72rem;
  color: var(--text-muted);
  text-decoration: none;
  transition: color var(--transition-fast);
}

.card-link:hover { color: #ff0000; }

.card-link .material-icons-round { font-size: 14px; }

/* List view card */
.video-grid.list-view .video-card {
  display: grid;
  grid-template-columns: 200px 1fr;
  border-radius: var(--radius-md);
}

.video-grid.list-view .video-card:hover {
  transform: translateX(4px);
}

.video-grid.list-view .card-thumbnail { aspect-ratio: 16 / 9; }

.video-grid.list-view .card-body {
  display: flex;
  flex-direction: column;
  justify-content: center;
  padding: 12px 20px;
}

.video-grid.list-view .card-title {
  -webkit-line-clamp: 1;
  line-clamp: 1;
  margin-bottom: 6px;
}

/* --- Chat Panel --- */
.chat-panel {
  width: 0;
  min-width: 0;
  background: var(--bg-secondary);
  border-left: 1px solid var(--border-primary);
  display: flex;
  flex-direction: column;
  transition: all var(--transition-slow);
  overflow: hidden;
  opacity: 0;
}

.chat-panel.open {
  width: var(--chat-width);
  min-width: var(--chat-width);
  opacity: 1;
}

.chat-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 16px 20px;
  border-bottom: 1px solid var(--border-primary);
  background: var(--bg-tertiary);
}

.chat-header-info {
  display: flex;
  align-items: center;
  gap: 12px;
}

.chat-header-info .material-icons-round {
  color: var(--accent-primary);
  font-size: 24px;
}

.chat-header-info h3 {
  font-size: 0.9rem;
  font-weight: 600;
}

.chat-header-sub {
  font-size: 0.7rem;
  color: var(--text-tertiary);
}

.chat-close-btn {
  background: none;
  border: none;
  color: var(--text-tertiary);
  cursor: pointer;
  padding: 4px;
  border-radius: var(--radius-sm);
  transition: all var(--transition-fast);
  display: flex;
}

.chat-close-btn:hover {
  color: var(--text-primary);
  background: var(--bg-card);
}

.chat-messages {
  flex: 1;
  overflow-y: auto;
  padding: 20px;
}

.chat-welcome {
  text-align: center;
  padding: 40px 20px;
}

.chat-welcome-icon { font-size: 3rem; margin-bottom: 16px; }

.chat-welcome h4 {
  font-size: 1.1rem;
  font-weight: 600;
  margin-bottom: 8px;
}

.chat-welcome p {
  font-size: 0.82rem;
  color: var(--text-secondary);
  margin-bottom: 20px;
  line-height: 1.5;
}

.chat-suggestions {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.chat-suggestion {
  background: var(--bg-tertiary);
  border: 1px solid var(--border-primary);
  border-radius: var(--radius-md);
  padding: 10px 14px;
  color: var(--text-secondary);
  font-size: 0.8rem;
  cursor: pointer;
  transition: all var(--transition-fast);
  text-align: left;
  font-family: inherit;
}

.chat-suggestion:hover {
  background: var(--bg-card-hover);
  border-color: var(--accent-primary);
  color: var(--text-primary);
}

.chat-message {
  margin-bottom: 16px;
  animation: messageIn 0.3s var(--ease-out);
}

@keyframes messageIn {
  from { opacity: 0; transform: translateY(8px); }
  to { opacity: 1; transform: translateY(0); }
}

.chat-message.user {
  display: flex;
  justify-content: flex-end;
}

.chat-message.user .message-bubble {
  background: var(--accent-gradient);
  color: #ffffff;
  border-radius: var(--radius-md) var(--radius-md) 4px var(--radius-md);
  max-width: 85%;
}

.message-bubble {
  padding: 10px 14px;
  font-size: 0.83rem;
  line-height: 1.55;
}

.chat-message.assistant .message-bubble {
  background: var(--bg-tertiary);
  border: 1px solid var(--border-primary);
  border-radius: var(--radius-md) var(--radius-md) var(--radius-md) 4px;
  color: var(--text-primary);
}

.message-source {
  margin-top: 8px;
  padding: 8px 12px;
  background: var(--bg-card);
  border-radius: var(--radius-sm);
  border-left: 3px solid var(--accent-primary);
}

.message-source-title {
  font-size: 0.78rem;
  font-weight: 600;
  color: var(--accent-primary);
  margin-bottom: 4px;
}

.message-source-excerpt {
  font-size: 0.75rem;
  color: var(--text-secondary);
  line-height: 1.5;
}

.message-source-link {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  font-size: 0.72rem;
  color: var(--accent-secondary);
  text-decoration: none;
  margin-top: 6px;
}

.message-source-link:hover { text-decoration: underline; }

.chat-input-area {
  padding: 16px 20px;
  border-top: 1px solid var(--border-primary);
  background: var(--bg-tertiary);
}

.chat-input-wrapper {
  display: flex;
  align-items: flex-end;
  gap: 8px;
  background: var(--bg-card);
  border: 1px solid var(--border-primary);
  border-radius: var(--radius-md);
  padding: 4px 4px 4px 14px;
  transition: border-color var(--transition-fast);
}

.chat-input-wrapper:focus-within {
  border-color: var(--accent-primary);
}

.chat-input-wrapper textarea {
  flex: 1;
  background: transparent;
  border: none;
  outline: none;
  color: var(--text-primary);
  font-size: 0.85rem;
  font-family: inherit;
  resize: none;
  padding: 8px 0;
  max-height: 100px;
  line-height: 1.4;
}

.chat-input-wrapper textarea::placeholder { color: var(--text-muted); }

.chat-send-btn {
  width: 36px;
  height: 36px;
  border-radius: var(--radius-sm);
  background: var(--accent-gradient);
  border: none;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all var(--transition-fast);
  flex-shrink: 0;
}

.chat-send-btn:hover { transform: scale(1.05); }

.chat-send-btn .material-icons-round {
  font-size: 18px;
  color: #ffffff;
}

.chat-disclaimer {
  display: block;
  font-size: 0.65rem;
  color: var(--text-muted);
  margin-top: 8px;
  text-align: center;
}

.typing-indicator {
  display: flex;
  gap: 4px;
  padding: 12px 14px;
}

.typing-dot {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--text-tertiary);
  animation: typingBounce 1.4s ease-in-out infinite;
}

.typing-dot:nth-child(2) { animation-delay: 0.2s; }
.typing-dot:nth-child(3) { animation-delay: 0.4s; }

@keyframes typingBounce {
  0%, 60%, 100% { transform: translateY(0); }
  30% { transform: translateY(-6px); }
}

/* --- Modal --- */
.modal-overlay {
  position: fixed;
  inset: 0;
  background: var(--bg-overlay);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  z-index: 200;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 24px;
  animation: fadeIn 0.2s ease;
}

.modal-overlay.hidden { display: none; }

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

.modal-content {
  background: var(--bg-secondary);
  border: 1px solid var(--border-primary);
  border-radius: var(--radius-xl);
  width: 100%;
  max-width: 960px;
  max-height: 90vh;
  overflow-y: auto;
  animation: modalSlideIn 0.3s var(--ease-out);
}

@keyframes modalSlideIn {
  from { opacity: 0; transform: translateY(20px) scale(0.97); }
  to { opacity: 1; transform: translateY(0) scale(1); }
}

.modal-header {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  padding: 24px 28px;
  border-bottom: 1px solid var(--border-primary);
  gap: 16px;
}

.modal-header h2 {
  font-size: 1.15rem;
  font-weight: 700;
  line-height: 1.4;
}

.modal-close-btn {
  background: var(--bg-tertiary);
  border: 1px solid var(--border-primary);
  color: var(--text-secondary);
  padding: 6px;
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: all var(--transition-fast);
  display: flex;
  flex-shrink: 0;
}

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

.modal-body { padding: 24px 28px; }

.modal-player {
  aspect-ratio: 16 / 9;
  border-radius: var(--radius-md);
  overflow: hidden;
  background: #000;
  margin-bottom: 20px;
}

.modal-player iframe {
  width: 100%;
  height: 100%;
  border: none;
}

.modal-info {
  /* spacing container */
}

.modal-meta {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 20px;
}

.modal-category-badge {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  font-size: 0.72rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.5px;
  padding: 4px 12px;
  border-radius: 20px;
}

.modal-duration {
  font-size: 0.82rem;
  color: var(--text-secondary);
  display: flex;
  align-items: center;
  gap: 4px;
}

.modal-transcript {
  background: var(--bg-card);
  border: 1px solid var(--border-primary);
  border-radius: var(--radius-md);
  overflow: hidden;
}

.transcript-header {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 12px 16px;
  border-bottom: 1px solid var(--border-primary);
  background: var(--bg-tertiary);
}

.transcript-header .material-icons-round {
  font-size: 18px;
  color: var(--accent-primary);
}

.transcript-header h4 {
  font-size: 0.82rem;
  font-weight: 600;
}

.transcript-content {
  padding: 16px;
  max-height: 300px;
  overflow-y: auto;
  font-size: 0.82rem;
  line-height: 1.7;
  color: var(--text-secondary);
}

.transcript-loading {
  text-align: center;
  color: var(--text-muted);
  font-style: italic;
}

/* --- Empty State --- */
.empty-state {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: 80px 40px;
  text-align: center;
}

.empty-state.hidden { display: none; }

.empty-state .material-icons-round {
  font-size: 64px;
  color: var(--text-muted);
  margin-bottom: 16px;
}

.empty-state h3 {
  font-size: 1.1rem;
  font-weight: 600;
  margin-bottom: 8px;
}

.empty-state p {
  font-size: 0.85rem;
  color: var(--text-secondary);
}

/* --- Mobile Sidebar Toggle --- */
.mobile-sidebar-btn {
  display: none;
  position: fixed;
  bottom: 20px;
  left: 20px;
  width: 48px;
  height: 48px;
  border-radius: 50%;
  background: var(--accent-gradient);
  border: none;
  color: #ffffff;
  cursor: pointer;
  z-index: 90;
  box-shadow: 0 4px 20px rgba(192, 57, 43, 0.25);
  align-items: center;
  justify-content: center;
}

/* Category badge colors */
.badge-governance { background: rgba(142, 68, 173, 0.12); color: #8e44ad; }
.badge-infrastructure { background: rgba(41, 128, 185, 0.12); color: #2980b9; }
.badge-sectoral { background: rgba(39, 174, 96, 0.12); color: #27ae60; }
.badge-social { background: rgba(231, 76, 60, 0.12); color: #c0392b; }
.badge-safety { background: rgba(192, 57, 43, 0.12); color: #c0392b; }
.badge-future { background: rgba(44, 62, 80, 0.12); color: #2c3e50; }
.badge-keynotes { background: rgba(230, 126, 34, 0.12); color: #d35400; }

/* --- Responsive --- */
@media (max-width: 1024px) {
  .sidebar {
    position: fixed;
    left: 0;
    top: var(--header-height);
    bottom: 0;
    z-index: 80;
    transform: translateX(-100%);
    transition: transform var(--transition-slow);
  }

  .sidebar.mobile-open {
    transform: translateX(0);
  }

  .sidebar.collapsed { transform: translateX(-100%); }

  .mobile-sidebar-btn { display: flex; }

  .chat-panel.open {
    position: fixed;
    right: 0;
    top: var(--header-height);
    bottom: 0;
    z-index: 80;
  }
}

@media (max-width: 768px) {
  .header { padding: 0 16px; }
  .header-center { margin: 0 12px; }
  .search-shortcut { display: none; }
  .stats { display: none; }
  .chat-toggle-label { display: none; }
  .chat-toggle-btn { padding: 8px; }

  .video-grid {
    grid-template-columns: 1fr;
    padding: 16px;
    gap: 12px;
  }

  .filter-bar { padding: 10px 16px; }

  .chat-panel.open {
    width: 100%;
    min-width: 100%;
  }

  .modal-content {
    border-radius: var(--radius-md);
  }

  .modal-header { padding: 16px 20px; }
  .modal-body { padding: 16px 20px; }
}

/* --- Utilities --- */
.hidden { display: none !important; }

/* Smooth loader shimmer */
@keyframes shimmer {
  0% { background-position: -200% 0; }
  100% { background-position: 200% 0; }
}

.skeleton {
  background: linear-gradient(90deg, var(--bg-tertiary) 25%, var(--bg-card-hover) 50%, var(--bg-tertiary) 75%);
  background-size: 200% 100%;
  animation: shimmer 1.5s linear infinite;
  border-radius: var(--radius-sm);
}

/* --- Footer --- */
.site-footer {
  text-align: center;
  padding: 16px 24px;
  font-size: 0.8rem;
  color: var(--text-muted);
  border-top: 1px solid var(--border-primary);
  background: var(--bg-secondary);
}

.site-footer a {
  color: var(--accent-primary);
  text-decoration: none;
  font-weight: 600;
}

.site-footer a:hover {
  text-decoration: underline;
}

/* Card fav button light mode adjustments */
.card-fav-btn {
  background: rgba(255, 255, 255, 0.85);
  color: var(--text-muted);
  box-shadow: 0 1px 4px rgba(0,0,0,0.1);
}

.card-fav-btn.active {
  color: var(--accent-primary);
  background: rgba(192, 57, 43, 0.1);
}

.card-fav-btn:hover {
  color: var(--accent-primary);
  background: rgba(192, 57, 43, 0.15);
}