/* ═══════════════════════════════════════════════════════════════
   SHIVANGI SCIENCE CLASSES — UI Components
   components.css
   ═══════════════════════════════════════════════════════════════ */

/* ─── CHAPTER CONTENT PANEL ──────────────────────────────────────── */
.chapter-body {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.45s cubic-bezier(0.4, 0, 0.2, 1);
}
.chapter-item.open .chapter-body {
  max-height: 5000px;
}

.chapter-body-inner {
  padding: 0 var(--space-lg) var(--space-lg);
  border-top: 1px solid var(--border);
}

/* ─── CONTENT TABS ───────────────────────────────────────────────── */
.content-tabs {
  display: flex;
  gap: var(--space-xs);
  padding: var(--space-md) 0 var(--space-md);
  border-bottom: 1px solid var(--border);
  margin-bottom: var(--space-lg);
  overflow-x: auto;
  scrollbar-width: none;
}
.content-tabs::-webkit-scrollbar { display: none; }

.tab-btn {
  display: inline-flex;
  align-items: center;
  gap: var(--space-xs);
  padding: 0.5rem 1rem;
  border-radius: var(--radius-full);
  font-size: 0.82rem;
  font-weight: 600;
  color: var(--text-muted);
  background: transparent;
  border: 1px solid transparent;
  white-space: nowrap;
  cursor: pointer;
  transition: var(--transition-fast);
}
.tab-btn:hover { color: var(--text-primary); background: var(--bg-card2); }
.tab-btn.active {
  color: var(--accent);
  background: var(--accent-light);
  border-color: var(--border);
}

/* ─── NOTES SECTION ──────────────────────────────────────────────── */
.notes-section {
  background: var(--bg-card);
  border: 1px solid var(--border);
  box-shadow: var(--shadow-sm);
  border-radius: var(--radius-md);
  padding: var(--space-lg);
  margin-bottom: var(--space-lg);
}

.notes-header {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  margin-bottom: var(--space-md);
}
.notes-icon {
  width: 32px;
  height: 32px;
  background: var(--grad-primary);
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  font-size: 0.8rem;
}
.notes-heading {
  font-size: 0.9rem;
  font-weight: 700;
  color: var(--accent);
}

.notes-body {
  font-family: var(--font-hindi);
  font-size: 0.92rem;
  color: var(--text-primary);
  line-height: 1.9;
}
.notes-body p { margin-bottom: var(--space-sm); }
.notes-body strong { color: #0F172A; font-weight: 700; }

.notes-body .highlight,
.notes-body em.highlight {
  background: var(--highlight-bg);
  color: var(--highlight-text);
  padding: 0.1em 0.35em;
  border-radius: 3px;
  font-weight: 600;
  font-style: normal;
}

/* Headings & lists inside detailed notes */
.notes-body h3 {
  font-size: 1rem;
  font-weight: 800;
  color: #0F172A;
  margin: var(--space-lg) 0 var(--space-sm);
  padding-bottom: 6px;
  border-bottom: 2px solid var(--border);
}
.notes-body h3:first-child { margin-top: 0; }
.notes-body h4 {
  font-size: 0.92rem;
  font-weight: 700;
  color: #0F172A;
  margin: var(--space-md) 0 var(--space-xs);
}
.notes-body ul, .notes-body ol {
  margin: var(--space-sm) 0 var(--space-md);
  padding-left: 1.4rem;
}
.notes-body li {
  margin-bottom: 6px;
}
.notes-body li > strong { color: #0F172A; font-weight: 700; }
.notes-body blockquote {
  margin: var(--space-sm) 0 var(--space-md);
  padding: var(--space-sm) var(--space-md);
  background: #FFFBEB;
  border-left: 3px solid #D97706;
  border-radius: var(--radius-sm);
}
.notes-body .formula-box {
  display: block;
  margin: var(--space-sm) 0;
  padding: var(--space-sm) var(--space-md);
  background: var(--code-bg);
  border: 1px dashed rgba(55,48,163,0.25);
  border-radius: var(--radius-sm);
  font-weight: 700;
  color: var(--accent);
  font-size: 0.95rem;
}

.notes-points {
  margin: var(--space-md) 0;
  padding-left: 0;
  list-style: none;
}
.notes-points li {
  position: relative;
  padding-left: 1.5rem;
  margin-bottom: var(--space-sm);
  font-family: var(--font-hindi);
  font-size: 0.9rem;
  color: var(--text-primary);
  line-height: 1.8;
}
.notes-points li::before {
  content: '▸';
  position: absolute;
  left: 0;
  color: var(--accent);
  font-size: 0.8rem;
  top: 3px;
}

/* ─── Q&A SECTION ────────────────────────────────────────────────── */
.qa-section { margin-bottom: var(--space-lg); }

/* BSEB textbook sectioned Q&A format */
.qa-section-group { margin-bottom: var(--space-lg); }
.qa-section-header {
  display: flex; align-items: center; gap: 8px;
  padding: 10px 16px; margin-bottom: var(--space-sm);
  background: #EFF6FF;
  border-left: 3px solid var(--accent);
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  font-size: 0.85rem; font-weight: 700;
  color: var(--accent);
}
.qa-section-header i { font-size: 0.75rem; }
.qa-section-group .qa-list { padding-left: 0; }

.qa-section-title {
  font-size: 0.9rem;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: var(--space-md);
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  padding: var(--space-sm) 0;
  border-bottom: 1px solid var(--border);
}
.qa-section-title i { color: var(--english-b); }

.qa-list { display: flex; flex-direction: column; gap: var(--space-sm); }

.qa-item {
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  background: var(--bg-card);
  overflow: hidden;
  transition: border-color var(--transition-fast);
  box-shadow: var(--shadow-sm);
}
.qa-item:hover { border-color: var(--border-glow); }

.qa-question {
  display: flex;
  align-items: flex-start;
  gap: var(--space-md);
  padding: var(--space-md) var(--space-lg);
  cursor: pointer;
  user-select: none;
  transition: background var(--transition-fast);
}
.qa-question:hover { background: var(--bg-card2); }

.qa-q-badge {
  width: 28px;
  height: 28px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--english-a), var(--english-b));
  color: white;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.7rem;
  font-weight: 700;
  flex-shrink: 0;
  margin-top: 2px;
}

.qa-q-text {
  font-family: var(--font-hindi);
  font-size: 0.9rem;
  font-weight: 600;
  color: #0F172A;
  line-height: 1.6;
  flex: 1;
}

.qa-toggle {
  color: var(--text-secondary);
  font-size: 0.7rem;
  flex-shrink: 0;
  margin-left: auto;
  transition: transform var(--transition-fast), color var(--transition-fast);
  align-self: center;
}
.qa-item.open .qa-toggle {
  transform: rotate(180deg);
  color: var(--accent);
}

.qa-answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.35s ease;
}
.qa-item.open .qa-answer { max-height: 800px; }

.qa-answer-inner {
  padding: var(--space-md) var(--space-lg) var(--space-lg);
  border-top: 1px solid var(--border);
  background: var(--bg-card2);
}

.qa-a-label {
  font-size: 0.72rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.8px;
  color: #166534;
  margin-bottom: var(--space-sm);
  display: flex;
  align-items: center;
  gap: var(--space-xs);
}
.qa-a-label::before { content: 'उत्तर →'; }

.qa-a-text {
  font-family: var(--font-hindi);
  font-size: 0.9rem;
  color: var(--text-primary);
  line-height: 1.9;
}

/* ─── MCQ SECTION ────────────────────────────────────────────────── */
.mcq-section { margin-bottom: var(--space-lg); }

.mcq-section-title {
  font-size: 0.9rem;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: var(--space-md);
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  padding: var(--space-sm) 0;
  border-bottom: 1px solid var(--border);
}
.mcq-section-title i { color: var(--science-b); }

.mcq-controls {
  display: flex;
  gap: var(--space-sm);
  margin-bottom: var(--space-md);
  flex-wrap: wrap;
}

.mcq-list {
  display: flex;
  flex-direction: column;
  gap: var(--space-md);
}

.mcq-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: var(--space-lg);
  transition: border-color var(--transition-fast);
  box-shadow: var(--shadow-sm);
}
.mcq-card:hover { border-color: var(--border-glow); }

.mcq-q-row {
  display: flex;
  align-items: flex-start;
  gap: var(--space-md);
  margin-bottom: var(--space-md);
}

.mcq-num {
  width: 28px;
  height: 28px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--science-a), var(--science-b));
  color: white;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.72rem;
  font-weight: 700;
  flex-shrink: 0;
}

.mcq-question {
  font-family: var(--font-hindi);
  font-size: 0.92rem;
  font-weight: 600;
  color: #0F172A;
  line-height: 1.6;
  flex: 1;
}

.mcq-options {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-sm);
  margin-bottom: var(--space-md);
}

.mcq-option {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  padding: 0.6rem var(--space-md);
  border: 1.5px solid #D1D5DB;
  border-radius: var(--radius-md);
  cursor: pointer;
  transition: var(--transition-fast);
  font-family: var(--font-hindi);
  font-size: 0.87rem;
  color: var(--text-primary);
  background: #FFFFFF;
  text-align: left;
  width: 100%;
}

.mcq-option:hover:not(.revealed) {
  border-color: var(--accent);
  background: var(--accent-light);
  color: var(--text-primary);
}

.mcq-option-key {
  width: 22px;
  height: 22px;
  border-radius: 50%;
  border: 1.5px solid #D1D5DB;
  background: #F9FAFB;
  color: var(--text-secondary);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.7rem;
  font-weight: 700;
  flex-shrink: 0;
  transition: var(--transition-fast);
}

.mcq-option.correct {
  border-color: #16A34A;
  background: var(--success-bg);
  color: var(--success-text);
}
.mcq-option.correct .mcq-option-key {
  background: var(--success);
  border-color: var(--success);
  color: white;
}

.mcq-option.wrong {
  border-color: #DC2626;
  background: var(--danger-bg);
  color: var(--danger-text);
}
.mcq-option.wrong .mcq-option-key {
  background: var(--danger);
  border-color: var(--danger);
  color: white;
}

.mcq-option.selected:not(.correct):not(.wrong) {
  border-color: var(--accent);
  background: var(--accent-light);
}
.mcq-option.selected:not(.correct):not(.wrong) .mcq-option-key {
  background: var(--accent);
  border-color: var(--accent);
  color: white;
}

.mcq-reveal-btn {
  display: inline-flex;
  align-items: center;
  gap: var(--space-xs);
  padding: 0.4rem 1rem;
  border: 1px solid rgba(56,239,125,0.4);
  border-radius: var(--radius-full);
  color: var(--science-b);
  font-size: 0.78rem;
  font-weight: 600;
  cursor: pointer;
  background: rgba(56,239,125,0.06);
  transition: var(--transition-fast);
}
.mcq-reveal-btn:hover {
  background: rgba(56,239,125,0.12);
  border-color: var(--science-b);
}

.mcq-explanation {
  margin-top: var(--space-sm);
  padding: var(--space-sm) var(--space-md);
  background: rgba(76,175,80,0.08);
  border-left: 3px solid var(--success);
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  font-size: 0.82rem;
  color: var(--text-secondary);
  font-family: var(--font-hindi);
  line-height: 1.7;
  display: none;
}
.mcq-explanation.show { display: block; animation: fadeInDown 0.3s ease; }

.mcq-explanation-label {
  font-size: 0.7rem;
  font-weight: 700;
  color: var(--success);
  text-transform: uppercase;
  letter-spacing: 0.5px;
  margin-bottom: 4px;
}

/* ─── SCORE DISPLAY ──────────────────────────────────────────────── */
.mcq-score-bar {
  display: flex;
  align-items: center;
  gap: var(--space-md);
  padding: var(--space-md) var(--space-lg);
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  margin-bottom: var(--space-md);
  font-size: 0.85rem;
  color: var(--text-primary);
  box-shadow: var(--shadow-sm);
}
.score-number { font-weight: 700; color: var(--accent); font-size: 1.1rem; }
.score-label  { color: var(--text-muted); }

/* ─── SEARCH RESULT CARDS ────────────────────────────────────────── */
.search-result-item {
  display: flex;
  align-items: flex-start;
  gap: var(--space-md);
  padding: var(--space-md);
  border-radius: var(--radius-md);
  border: 1px solid var(--border);
  background: var(--bg-card);
  margin-bottom: var(--space-sm);
  cursor: pointer;
  transition: var(--transition-fast);
  text-decoration: none;
}
.search-result-item:hover { border-color: var(--border-glow); background: var(--bg-card2); text-decoration: none; }

.search-result-icon {
  width: 36px;
  height: 36px;
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.9rem;
  color: white;
  flex-shrink: 0;
}
.search-result-title {
  font-size: 0.9rem;
  font-weight: 600;
  color: #0F172A;
  margin-bottom: 2px;
}
.search-result-meta {
  font-size: 0.75rem;
  color: var(--text-muted);
  display: flex;
  gap: var(--space-sm);
}
.search-no-results {
  text-align: center;
  color: var(--text-muted);
  padding: var(--space-xl);
  font-size: 0.9rem;
}

/* ─── ABOUT PAGE ─────────────────────────────────────────────────── */
.about-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-xl);
  margin-bottom: var(--space-2xl);
}
.feature-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: var(--space-xl);
  transition: var(--transition);
}
.feature-card:hover { border-color: var(--border-glow); transform: translateY(-4px); }
.feature-icon {
  width: 48px;
  height: 48px;
  border-radius: var(--radius-md);
  background: var(--accent);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.2rem;
  color: white;
  margin-bottom: var(--space-md);
}
.feature-title { font-size: 1.05rem; font-weight: 700; color: #0F172A; margin-bottom: var(--space-xs); }
.feature-desc  { font-size: 0.88rem; color: var(--text-secondary); line-height: 1.7; }

/* ─── ABOUT PAGE ─────────────────────────────────────────────────── */
.about-hero {
  position: relative;
  overflow: hidden;
  background: linear-gradient(135deg, #EFF6FF 0%, #F0FDF4 50%, #EFF6FF 100%);
  padding: var(--space-3xl) 0;
}
.about-hero-bg {
  position: absolute;
  inset: 0;
  background:
    radial-gradient(ellipse 60% 70% at 15% 50%, rgba(29,78,216,0.06) 0%, transparent 60%),
    radial-gradient(ellipse 50% 60% at 85% 30%, rgba(16,185,129,0.05) 0%, transparent 50%);
  z-index: 0;
}
.about-hero-inner {
  position: relative;
  z-index: 1;
  display: flex;
  align-items: center;
  gap: var(--space-3xl);
}
.about-hero-text { flex: 1; }
.about-hero-title {
  font-size: clamp(2rem, 5vw, 3rem);
  font-weight: 800;
  color: #0F172A;
  line-height: 1.15;
  margin: var(--space-sm) 0 var(--space-md);
}
.about-hero-sub {
  font-size: 1rem;
  color: var(--text-secondary);
  line-height: 1.8;
  max-width: 500px;
}
.about-hero-photo-wrap {
  position: relative;
  flex-shrink: 0;
  width: 200px;
  height: 200px;
}
.about-hero-photo {
  width: 100%;
  height: 100%;
  border-radius: 50%;
  object-fit: cover;
  border: 5px solid #fff;
  box-shadow: 0 8px 40px rgba(29,78,216,0.15), 0 0 0 3px rgba(29,78,216,0.08);
  position: relative;
  z-index: 1;
}
.about-hero-ring {
  position: absolute;
  inset: -6px;
  border-radius: 50%;
  border: 3px solid transparent;
  background: linear-gradient(135deg, var(--accent), #14B8A6, var(--accent)) border-box;
  -webkit-mask: linear-gradient(#fff 0 0) padding-box, linear-gradient(#fff 0 0);
  -webkit-mask-composite: xor;
  mask-composite: exclude;
  animation: ring-spin 4s linear infinite;
}
.about-section { padding: var(--space-3xl) 0; }
.about-section-alt { background: var(--bg-surface); }
.about-section-title {
  font-size: clamp(1.5rem, 3vw, 2rem);
  font-weight: 800;
  color: #0F172A;
  margin: var(--space-xs) 0 var(--space-sm);
}
/* Teacher Layout */
.about-teacher-layout {
  display: flex;
  align-items: center;
  gap: var(--space-3xl);
}
.about-teacher-photo-col { flex-shrink: 0; }
.about-teacher-photo-frame {
  position: relative;
  width: 240px;
  height: 240px;
}
.about-teacher-photo {
  width: 100%;
  height: 100%;
  border-radius: var(--radius-xl);
  object-fit: cover;
  border: 4px solid #fff;
  box-shadow: 0 8px 32px rgba(29,78,216,0.12);
  position: relative;
  z-index: 1;
  transition: transform 0.3s ease;
}
.about-teacher-photo:hover { transform: scale(1.02); }
.about-teacher-photo-glow {
  position: absolute;
  inset: -10px;
  background: radial-gradient(circle, rgba(29,78,216,0.1) 0%, transparent 70%);
  border-radius: var(--radius-xl);
  z-index: 0;
}
.about-teacher-info-col { flex: 1; }
.about-teacher-role {
  font-size: 0.9rem;
  color: var(--accent);
  font-weight: 600;
  margin-bottom: var(--space-md);
}
.about-teacher-bio {
  font-size: 0.95rem;
  color: var(--text-secondary);
  line-height: 1.8;
  margin-bottom: var(--space-xl);
}
.about-teacher-stats-row {
  display: flex;
  gap: var(--space-xl);
}
.about-teacher-stat {
  text-align: center;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: var(--space-md) var(--space-lg);
  min-width: 100px;
}
.about-teacher-stat-num {
  font-size: 1.4rem;
  font-weight: 800;
  color: var(--accent);
}
.about-teacher-stat-label {
  font-size: 0.72rem;
  color: var(--text-muted);
  font-weight: 500;
  margin-top: 2px;
}
/* Results Grid */
.about-results-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--space-xl);
  margin-top: var(--space-xl);
}
.about-result-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  overflow: hidden;
  transition: var(--transition);
}
.about-result-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 8px 32px rgba(29,78,216,0.1);
}
.about-result-img-wrap {
  position: relative;
  width: 100%;
  aspect-ratio: 4/3;
  overflow: hidden;
  background: #f1f5f9;
  border-radius: var(--radius-md) var(--radius-md) 0 0;
}
.about-result-img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.4s ease;
}
.about-result-card:hover .about-result-img { transform: scale(1.05); }
.about-result-view {
  position: absolute;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  background: rgba(0,0,0,0.3);
  opacity: 0;
  transition: opacity 0.3s ease;
}
.about-result-view i {
  color: #fff;
  font-size: 1.5rem;
  background: rgba(29,78,216,0.85);
  width: 48px;
  height: 48px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: 0 4px 16px rgba(0,0,0,0.25);
}
.about-result-img-wrap:hover .about-result-view { opacity: 1; }
.about-result-label {
  padding: var(--space-md);
  font-size: 0.85rem;
  font-weight: 600;
  color: #0F172A;
  text-align: center;
}
/* Mission Grid */
.about-mission-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-xl);
  margin-top: var(--space-xl);
}
.about-mission-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: var(--space-xl);
  transition: var(--transition);
}
.about-mission-card:hover {
  border-color: var(--border-glow);
  transform: translateY(-4px);
}
.about-mission-icon {
  width: 48px;
  height: 48px;
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.2rem;
  color: white;
  margin-bottom: var(--space-md);
}
.about-mission-card h3 {
  font-size: 1.05rem;
  font-weight: 700;
  color: #0F172A;
  margin-bottom: var(--space-xs);
}
.about-mission-card p {
  font-size: 0.88rem;
  color: var(--text-secondary);
  line-height: 1.7;
}
/* Contact Grid */
.about-contact-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--space-xl);
  margin-top: var(--space-xl);
}
.about-contact-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: var(--space-xl);
  text-align: center;
  transition: var(--transition);
}
.about-contact-card:hover {
  border-color: var(--border-glow);
  transform: translateY(-4px);
}
.about-contact-icon {
  width: 52px;
  height: 52px;
  border-radius: 50%;
  background: rgba(29,78,216,0.08);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.2rem;
  color: var(--accent);
  margin: 0 auto var(--space-md);
}
.about-contact-card h3 {
  font-size: 1rem;
  font-weight: 700;
  color: #0F172A;
  margin-bottom: var(--space-sm);
}
.about-contact-text {
  font-size: 0.88rem;
  color: var(--text-secondary);
  line-height: 1.6;
  margin-bottom: var(--space-xs);
n}
.about-contact-hindi {
  font-size: 0.82rem;
  color: var(--text-muted);
  font-weight: 500;
}
.about-contact-link {
  display: block;
  font-size: 0.95rem;
  font-weight: 600;
  color: var(--accent);
  text-decoration: none;
  margin-bottom: var(--space-xs);
  transition: color 0.2s;
}
.about-contact-link:hover { color: var(--success); }
/* CTA Section */
.about-cta {
  background: linear-gradient(135deg, var(--accent), #14B8A6);
  padding: var(--space-3xl) 0;
}
.about-cta-title {
  font-size: clamp(1.3rem, 3vw, 1.8rem);
  font-weight: 800;
  color: #fff;
  margin-bottom: var(--space-md);
}
.about-cta-desc {
  font-size: 1rem;
  color: rgba(255,255,255,0.85);
  max-width: 600px;
  margin: 0 auto var(--space-xl);
  line-height: 1.7;
}
.about-cta-actions {
  display: flex;
  gap: var(--space-md);
  justify-content: center;
  flex-wrap: wrap;
}
.about-cta-actions .btn-primary {
  background: #fff;
  color: var(--accent);
}
.about-cta-actions .btn-primary:hover { background: rgba(255,255,255,0.9); }
.about-cta-actions .btn-outline {
  border-color: rgba(255,255,255,0.5);
  color: #fff;
}
.about-cta-actions .btn-outline:hover { background: rgba(255,255,255,0.1); }
/* About Responsive */
@media (max-width: 900px) {
  .about-hero-inner { flex-direction: column; text-align: center; }
  .about-hero-photo-wrap { display: none; }
  .about-teacher-layout { flex-direction: column; text-align: center; }
  .about-teacher-photo-frame { width: 180px; height: 180px; }
  .about-teacher-stats-row { justify-content: center; }
  .about-results-grid { grid-template-columns: 1fr; max-width: 500px; margin-left: auto; margin-right: auto; }
  .about-mission-grid { grid-template-columns: 1fr; }
  .about-contact-grid { grid-template-columns: 1fr; max-width: 400px; margin-left: auto; margin-right: auto; }
}
@media (max-width: 640px) {
  .about-results-grid { grid-template-columns: 1fr; }
  .about-teacher-stats-row { flex-wrap: wrap; gap: var(--space-sm); }
}

/* ─── EMPTY / COMING SOON STATE ──────────────────────────────────── */
.coming-soon {
  text-align: center;
  padding: var(--space-3xl) var(--space-lg);
}
.coming-soon-icon {
  font-size: 4rem;
  margin-bottom: var(--space-lg);
  opacity: 0.5;
}
.coming-soon h3 { font-size: 1.4rem; font-weight: 700; margin-bottom: var(--space-sm); }
.coming-soon p  { color: var(--text-muted); font-size: 0.9rem; max-width: 400px; margin: 0 auto; }

/* ─── CHIP / TAG ─────────────────────────────────────────────────── */
.chip {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  padding: 3px 10px;
  border-radius: var(--radius-full);
  font-size: 0.72rem;
  font-weight: 600;
  border: 1px solid;
}
.chip-science { color: #0F766E; border-color: #99F6E4; background: #F0FDFA; }
.chip-english { color: #1D4ED8; border-color: #BFDBFE; background: #EFF6FF; }
.chip-hindi   { color: #92400E; border-color: #FDE68A; background: #FFFBEB; }
.chip-sst     { color: #9D174D; border-color: #FBCFE8; background: #FDF2F8; }
.chip-math    { color: #5B21B6; border-color: #DDD6FE; background: #F5F3FF; }
.chip-class   { color: var(--accent); border-color: #BFDBFE; background: #EFF6FF; }

/* ─── FLOATING SUBJECT ICON ──────────────────────────────────────── */
.subject-float-icon {
  position: absolute;
  right: var(--space-xl);
  top: 50%;
  transform: translateY(-50%);
  font-size: 5rem;
  opacity: 0.07;
  pointer-events: none;
}

/* ─── CHAPTER PAGE FULL ──────────────────────────────────────────── */
.chapter-page-header {
  padding: var(--space-xl) 0 var(--space-lg);
  border-bottom: 1px solid var(--border);
  margin-bottom: var(--space-xl);
}
.chapter-page-num {
  font-size: 0.75rem;
  font-weight: 600;
  color: var(--text-muted);
  letter-spacing: 1px;
  text-transform: uppercase;
  margin-bottom: var(--space-xs);
}
.chapter-page-title {
  font-size: clamp(1.5rem, 4vw, 2.2rem);
  font-weight: 800;
  margin-bottom: var(--space-xs);
}
.chapter-page-title-hi {
  font-family: var(--font-hindi);
  font-size: 1.1rem;
  color: var(--text-secondary);
  font-weight: 500;
}

/* ─── ALL REVEAL ANIMATION ───────────────────────────────────────── */
.reveal {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 0.5s ease, transform 0.5s ease;
}
.reveal.visible { opacity: 1; transform: translateY(0); }

/* ─── LANGUAGE TOGGLE BUTTON ─────────────────────────────────────── */
.lang-toggle-btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 0.45rem 0.9rem;
  border-radius: var(--radius-full);
  background: var(--bg-card2);
  border: 1px solid var(--border);
  color: var(--text-secondary);
  font-size: 0.8rem;
  font-weight: 600;
  cursor: pointer;
  transition: var(--transition-fast);
  text-decoration: none;
}
.lang-toggle-btn:hover {
  background: var(--accent-light);
  border-color: var(--border-glow);
  color: var(--accent);
  transform: translateY(-1px);
}
.lang-toggle-btn i { font-size: 0.9rem; }

/* ─── BOOK-LIKE NAVIGATION BAR ─────────────────────────────────── */
.book-nav-bar {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  padding: var(--space-md) 0;
  margin-bottom: var(--space-lg);
  border-bottom: 2px solid var(--border);
  overflow-x: auto;
  scrollbar-width: none;
}
.book-nav-bar::-webkit-scrollbar { display: none; }

.book-nav-link {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 0.5rem 1rem;
  border-radius: var(--radius-full);
  font-size: 0.82rem;
  font-weight: 600;
  color: var(--text-muted);
  background: transparent;
  border: 1px solid transparent;
  white-space: nowrap;
  cursor: pointer;
  text-decoration: none;
  transition: var(--transition-fast);
}
.book-nav-link:hover {
  color: var(--text-primary);
  background: var(--bg-card2);
  text-decoration: none;
}
.book-nav-link.active {
  color: var(--accent);
  background: var(--accent-light);
  border-color: #BFDBFE;
  text-decoration: none;
}
.book-nav-sep {
  color: var(--text-muted);
  font-size: 0.8rem;
  opacity: 0.4;
}

/* ─── BOOK SECTION DIVIDERS ─────────────────────────────────────── */
.book-section {
  margin-bottom: var(--space-2xl);
}

.book-section-divider {
  display: flex;
  align-items: center;
  gap: var(--space-md);
  margin-bottom: var(--space-xl);
  padding: var(--space-md) 0;
}

.book-divider-line {
  flex: 1;
  height: 1px;
  background: linear-gradient(to right, transparent, var(--border), transparent);
}

.book-divider-icon {
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background: var(--grad-primary);
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  font-size: 0.9rem;
  flex-shrink: 0;
}

.book-divider-text {
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--text-primary);
  white-space: nowrap;
}

.book-section-subtitle {
  font-size: 0.82rem;
  color: var(--text-secondary);
  margin-bottom: var(--space-lg);
  padding: var(--space-sm) var(--space-md);
  background: rgba(255,255,255,0.02);
  border-radius: var(--radius-sm);
  border-left: 3px solid var(--accent);
  display: flex;
  align-items: center;
  gap: var(--space-sm);
}
.book-section-subtitle i {
  color: var(--accent);
  font-size: 0.75rem;
}

/* ─── CHAPTER END MARKER ────────────────────────────────────────── */
.book-chapter-end {
  text-align: center;
  padding: var(--space-2xl) 0 var(--space-xl);
  margin-top: var(--space-xl);
}

.book-end-ornament {
  color: var(--accent);
  font-size: 1.2rem;
  letter-spacing: 8px;
  margin-bottom: var(--space-sm);
  opacity: 0.6;
}

.book-end-text {
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--text-muted);
  font-style: italic;
}

/* ─── RESPONSIVE FIXES ───────────────────────────────────────────── */
@media (max-width: 768px) {
  .mcq-options { grid-template-columns: 1fr; }
  .about-grid  { grid-template-columns: 1fr; }
  .book-nav-bar { gap: 4px; }
  .book-nav-link { padding: 0.4rem 0.8rem; font-size: 0.78rem; }
  .book-divider-text { font-size: 0.9rem; }
}

@media (max-width: 480px) {
  .chapter-tags { display: none; }
  .content-tabs { gap: 4px; }
  .tab-btn { padding: 0.4rem 0.7rem; font-size: 0.75rem; }
  .book-nav-sep { display: none; }
}

/* ═══════════════════════════════════════════════════════════════
   CHAPTER PAGE — Full Dedicated Page Layout
   ═══════════════════════════════════════════════════════════════ */

/* ─── BOOK GROUP (Subject Page) ─────────────────────────────────── */
.book-group {
  margin-bottom: var(--space-2xl);
}

.book-group-header {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  padding: var(--space-md) 0;
  margin-bottom: var(--space-md);
  border-bottom: 2px solid var(--border);
  font-size: 1rem;
  font-weight: 700;
  color: var(--text-primary);
}
.book-group-header i {
  color: var(--accent);
  font-size: 0.9rem;
}

.book-chapter-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
  gap: var(--space-md);
}

.book-chapter-card {
  display: flex;
  align-items: center;
  gap: var(--space-md);
  padding: var(--space-md) var(--space-lg);
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  text-decoration: none;
  transition: var(--transition);
  cursor: pointer;
}
.book-chapter-card:hover {
  border-color: var(--accent);
  background: var(--bg-card2);
  transform: translateY(-2px);
  box-shadow: 0 8px 24px rgba(0,0,0,0.15);
}
.book-chapter-card.coming-soon {
  opacity: 0.5;
}

.bch-num {
  width: 40px;
  height: 40px;
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.9rem;
  font-weight: 800;
  color: white;
  flex-shrink: 0;
}

.bch-body {
  flex: 1;
  min-width: 0;
}

.bch-title {
  font-size: 0.9rem;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 2px;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.bch-subtitle {
  font-size: 0.78rem;
  color: var(--text-muted);
  margin-bottom: 6px;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.bch-stats {
  display: flex;
  gap: var(--space-md);
  font-size: 0.72rem;
  color: var(--text-muted);
}
.bch-stats span {
  display: flex;
  align-items: center;
  gap: 4px;
}
.bch-stats i {
  font-size: 0.65rem;
}

.bch-arrow {
  color: var(--text-muted);
  font-size: 0.8rem;
  transition: transform 0.2s, color 0.2s;
  flex-shrink: 0;
}
.book-chapter-card:hover .bch-arrow {
  transform: translateX(4px);
  color: var(--accent);
}

/* ─── CHAPTER HERO ───────────────────────────────────────────────── */
.ch-hero {
  background: var(--bg-surface);
  border-bottom: 1px solid var(--border);
  padding: var(--space-2xl) 0;
}

.ch-hero-inner {
  display: flex;
  align-items: center;
  gap: var(--space-xl);
}

.ch-hero-num {
  width: 64px;
  height: 64px;
  border-radius: var(--radius-lg);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.6rem;
  font-weight: 900;
  color: white;
  flex-shrink: 0;
  box-shadow: 0 8px 24px rgba(0,0,0,0.3);
}

.ch-hero-text {
  flex: 1;
}

.ch-hero-title {
  font-size: clamp(1.4rem, 3vw, 2rem);
  font-weight: 800;
  color: var(--text-primary);
  margin-bottom: var(--space-xs);
}

.ch-hero-subtitle {
  font-size: 0.95rem;
  color: var(--text-secondary);
  margin-bottom: var(--space-md);
}

.ch-hero-meta {
  display: flex;
  align-items: center;
  gap: var(--space-md);
  flex-wrap: wrap;
  font-size: 0.8rem;
  color: var(--text-muted);
}
.ch-hero-meta span {
  display: flex;
  align-items: center;
  gap: 4px;
}

/* ─── CHAPTER NAV BAR (Sticky) ──────────────────────────────────── */
.ch-nav-wrapper {
  position: sticky;
  top: 60px;
  z-index: 100;
  background: var(--bg-root);
  border-bottom: 1px solid var(--border);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
}

.ch-nav-bar {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  padding: var(--space-sm) 0;
  overflow-x: auto;
  scrollbar-width: none;
}
.ch-nav-bar::-webkit-scrollbar { display: none; }

/* ─── CHAPTER CONTENT AREA ───────────────────────────────────────── */
.ch-content-area {
  padding-top: var(--space-xl);
  padding-bottom: var(--space-3xl);
}

.ch-layout {
  display: grid;
  grid-template-columns: 1fr 280px;
  gap: var(--space-2xl);
  align-items: start;
}

.ch-main {
  min-width: 0;
}

.ch-section {
  margin-bottom: var(--space-3xl);
}

.ch-section-divider {
  display: flex;
  align-items: center;
  gap: var(--space-md);
  margin-bottom: var(--space-xl);
  padding: var(--space-md) 0;
}

.ch-div-line {
  flex: 1;
  height: 2px;
  background: linear-gradient(to right, transparent, var(--border), transparent);
}

.ch-div-icon {
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background: var(--grad-primary);
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  font-size: 1rem;
  flex-shrink: 0;
}

.ch-div-text {
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--text-primary);
  white-space: nowrap;
}

.ch-section-info {
  font-size: 0.82rem;
  color: var(--text-secondary);
  margin-bottom: var(--space-lg);
  padding: var(--space-sm) var(--space-md);
  background: rgba(255,255,255,0.02);
  border-radius: var(--radius-sm);
  border-left: 3px solid var(--accent);
  display: flex;
  align-items: center;
  gap: var(--space-sm);
}
.ch-section-info i {
  color: var(--accent);
  font-size: 0.75rem;
}

/* ─── FORMULAS PANEL ────────────────────────────────────────────── */
.formula-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: var(--space-md);
}

.formula-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-left: 4px solid var(--accent);
  border-radius: var(--radius-md);
  padding: var(--space-lg);
  transition: transform 0.15s, border-color 0.15s;
}

.formula-card:hover {
  transform: translateY(-2px);
  border-color: rgba(56,239,125,0.25);
}

.formula-label {
  font-size: 0.72rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--text-muted);
  margin-bottom: var(--space-sm);
  display: flex;
  align-items: center;
  gap: 6px;
}

.formula-label i {
  color: var(--accent);
}

.formula-expression {
  font-family: 'Courier New', monospace;
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--code-text);
  background: var(--code-bg);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: var(--space-sm) var(--space-md);
  margin-bottom: var(--space-sm);
  word-break: break-word;
  overflow-wrap: anywhere;
}

.formula-desc {
  font-size: 0.85rem;
  color: var(--text-secondary);
  margin-bottom: var(--space-sm);
}

.formula-vars {
  font-size: 0.78rem;
  color: var(--text-muted);
  line-height: 1.6;
}

.formula-vars strong {
  color: var(--accent);
}

/* ─── SOLVED EXAMPLES PANEL ─────────────────────────────────────── */
.examples-section {
  display: flex;
  flex-direction: column;
  gap: var(--space-lg);
}

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

.example-header {
  padding: var(--space-sm) var(--space-lg);
  background: var(--bg-card2);
  border-bottom: 1px solid var(--border);
}

.example-badge {
  font-size: 0.78rem;
  font-weight: 700;
  color: var(--accent);
  display: inline-flex;
  align-items: center;
  gap: 6px;
}

.example-problem,
.example-solution {
  padding: var(--space-md) var(--space-lg);
}

.example-solution {
  border-top: 1px dashed var(--border);
  background: rgba(56,239,125,0.03);
}

.example-label {
  font-size: 0.75rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--text-muted);
  margin-bottom: var(--space-sm);
  display: flex;
  align-items: center;
  gap: 6px;
}

.example-label i {
  color: var(--accent);
}

.example-problem p,
.example-solution p {
  margin: 0 0 0.35rem 0;
  font-size: 0.92rem;
  line-height: 1.7;
  color: var(--text-secondary);
}

.example-solution p:last-child {
  margin-bottom: 0;
}

/* ─── CHAPTER SIDEBAR ────────────────────────────────────────────── */
.ch-sidebar {
  position: sticky;
  top: 120px;
}

.ch-sidebar-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: var(--space-lg);
  margin-bottom: var(--space-md);
}

.ch-sidebar-title {
  font-size: 0.85rem;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: var(--space-md);
  display: flex;
  align-items: center;
  gap: var(--space-sm);
}
.ch-sidebar-title i {
  color: var(--accent);
  font-size: 0.8rem;
}

.ch-sidebar-list {
  display: flex;
  flex-direction: column;
  gap: 2px;
}
.ch-sidebar-list a {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  padding: 6px 10px;
  border-radius: var(--radius-sm);
  font-size: 0.8rem;
  color: var(--text-secondary);
  text-decoration: none;
  transition: var(--transition-fast);
}
.ch-sidebar-list a:hover {
  background: var(--bg-card2);
  color: var(--text-primary);
}
.ch-sidebar-list a.current {
  background: var(--accent-light);
  color: var(--accent);
  font-weight: 600;
}
.ch-sb-num {
  font-weight: 700;
  color: var(--text-muted);
  width: 22px;
  flex-shrink: 0;
}

/* ─── CHAPTER END MARKER ────────────────────────────────────────── */
.ch-end-marker {
  text-align: center;
  padding: var(--space-2xl) 0;
  margin: var(--space-xl) 0;
  border-top: 1px solid var(--border);
}

.ch-end-ornament {
  color: var(--accent);
  font-size: 1.2rem;
  letter-spacing: 8px;
  margin-bottom: var(--space-sm);
  opacity: 0.6;
}

.ch-end-text {
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--text-muted);
  font-style: italic;
}

/* ─── CHAPTER PREV / NEXT ───────────────────────────────────────── */
.ch-prev-next {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-md);
  margin-top: var(--space-xl);
}

.ch-prev, .ch-next {
  display: flex;
  align-items: center;
  gap: var(--space-md);
  padding: var(--space-lg);
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  text-decoration: none;
  transition: var(--transition);
}
.ch-prev:hover, .ch-next:hover {
  border-color: var(--accent);
  background: var(--bg-card2);
  transform: translateY(-2px);
}
.ch-next {
  justify-content: flex-end;
  text-align: right;
}

.ch-pn-label {
  font-size: 0.72rem;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.5px;
  margin-bottom: 2px;
}
.ch-pn-title {
  font-size: 0.88rem;
  font-weight: 600;
  color: var(--text-primary);
}

/* ─── DEEP CONCEPTS / ADVANCED TOPICS ───────────────────────────── */
.notes-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: var(--space-lg);
}

.notes-card-header {
  font-size: 0.95rem;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: var(--space-lg);
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  padding-bottom: var(--space-sm);
  border-bottom: 1px solid var(--border);
}

.deep-concepts-grid, .advanced-topics-grid {
  display: grid;
  gap: var(--space-md);
}

.deep-concept-item, .advanced-topic-item {
  padding: var(--space-md);
  border-radius: var(--radius-sm);
  border-left: 3px solid;
}
.deep-concept-item {
  background: rgba(249,83,198,0.04);
  border-left-color: #f953c6;
}
.advanced-topic-item {
  background: #F0FDF4;
  border-left-color: #16A34A;
}

.dc-title, .at-title {
  font-size: 0.88rem;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: var(--space-sm);
  display: flex;
  align-items: center;
  gap: var(--space-sm);
}
.dc-title i { color: #7C3AED; }
.at-title i { color: #16A34A; }

.dc-content, .at-content {
  font-family: var(--font-hindi);
  font-size: 0.88rem;
  color: var(--text-secondary);
  line-height: 1.8;
}

/* ─── IMPORTANT DATES & EVENTS ────────────────────────────────── */
.important-dates-list {
  display: flex;
  flex-direction: column;
  gap: var(--space-sm);
}

.important-date-item {
  padding: var(--space-md);
  border-radius: var(--radius-sm);
  background: rgba(247,151,30,0.05);
  border-left: 3px solid #f7971e;
}

.id-date {
  font-size: 0.82rem;
  font-weight: 700;
  color: #f7971e;
  margin-bottom: 4px;
  display: flex;
  align-items: center;
  gap: 6px;
}
.id-date i { font-size: 0.75rem; }

.id-event {
  font-size: 0.9rem;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 4px;
}

.id-explanation {
  font-family: var(--font-hindi);
  font-size: 0.86rem;
  color: var(--text-secondary);
  line-height: 1.8;
}

/* Inline dates list (basic notes panel) */
.important-dates-list.notes-points li::before {
  content: '🗓';
  color: #f7971e;
}

/* ─── CHAPTER PAGE RESPONSIVE ───────────────────────────────────── */
@media (max-width: 1024px) {
  .ch-layout {
    grid-template-columns: 1fr;
  }
  .ch-sidebar {
    position: static;
  }
  .ch-hero-inner {
    flex-direction: column;
    text-align: center;
    align-items: center;
  }
  .ch-hero-meta {
    justify-content: center;
  }
}

@media (max-width: 768px) {
  .book-chapter-grid {
    grid-template-columns: 1fr;
  }
  .ch-prev-next {
    grid-template-columns: 1fr;
  }
  .ch-next {
    justify-content: flex-start;
    text-align: left;
    flex-direction: row-reverse;
  }
  .ch-nav-wrapper {
    top: 52px;
  }
  .ch-hero-num {
    width: 48px;
    height: 48px;
    font-size: 1.2rem;
  }
  .ch-div-text {
    font-size: 0.95rem;
    white-space: normal;
  }
}

@media (max-width: 480px) {
  .ch-hero {
    padding: var(--space-lg) 0;
  }
  .ch-section-divider {
    flex-wrap: wrap;
    justify-content: center;
  }
  .ch-div-text {
    width: 100%;
    text-align: center;
  }
}

/* ─── CHAPTER PAGE NOTES - ENHANCED ────────────────────────────── */
.ch-main .notes-section {
  background: var(--bg-card);
  border: 1px solid var(--border);
  box-shadow: var(--shadow-sm);
  border-radius: var(--radius-md);
  padding: var(--space-xl);
}

.ch-main .notes-body {
  font-size: 0.95rem;
  line-height: 2;
}

.ch-main .qa-item {
  margin-bottom: var(--space-md);
}

.ch-main .mcq-card {
  margin-bottom: var(--space-md);
}

.ch-main .mcq-options {
  grid-template-columns: 1fr 1fr;
}

@media (max-width: 640px) {
  .ch-main .mcq-options {
    grid-template-columns: 1fr;
  }
}

/* ═══════════════════════════════════════════════════════════════
   UX IMPROVEMENTS — Reading Progress, Continue Reading,
   Q&A Tools, MCQ Score
   ═══════════════════════════════════════════════════════════════ */

/* ─── READING PROGRESS BAR ─────────────────────────────────────── */
.reading-progress {
  position: fixed;
  top: 0;
  left: 0;
  height: 3px;
  width: 0;
  background: linear-gradient(90deg, var(--accent), #0F766E, #7C3AED);
  z-index: 3000;
  opacity: 0;
  transition: opacity 0.2s ease, width 0.1s linear;
  pointer-events: none;
  border-radius: 0 var(--radius-full) var(--radius-full) 0;
  box-shadow: 0 0 8px rgba(38, 208, 206, 0.5);
}
.reading-progress.visible { opacity: 1; }

/* ─── CONTINUE READING CARD (Home) ─────────────────────────────── */
.continue-reading { margin-top: var(--space-lg); }
.continue-reading-card {
  display: flex;
  align-items: center;
  gap: var(--space-md);
  background: var(--bg-card);
  border: 1px solid var(--border-glow);
  border-radius: var(--radius-lg);
  padding: var(--space-md) var(--space-lg);
  box-shadow: var(--shadow-md);
  flex-wrap: wrap;
}
.continue-reading-icon {
  width: 48px;
  height: 48px;
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  font-size: 1.2rem;
  flex-shrink: 0;
}
.continue-reading-body { flex: 1; min-width: 200px; }
.continue-reading-label {
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.5px;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 2px;
}
.continue-reading-label i { margin-right: 4px; }
.continue-reading-title {
  font-family: var(--font-hindi);
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--text-primary);
}
.continue-reading-meta {
  font-size: 0.78rem;
  color: var(--text-muted);
  margin-top: 2px;
}
.continue-reading-btn { flex-shrink: 0; }

/* ─── Q&A TOOLS (Expand / Collapse All) ────────────────────────── */
.qa-tools {
  display: flex;
  gap: var(--space-sm);
  margin-bottom: var(--space-lg);
  flex-wrap: wrap;
}

/* ─── MCQ SCORE CHIP ───────────────────────────────────────────── */
.mcq-score-chip {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  margin-left: auto;
  padding: 0.35rem 0.9rem;
  border-radius: var(--radius-full);
  background: rgba(249, 83, 198, 0.12);
  border: 1px solid rgba(249, 83, 198, 0.35);
  color: var(--math-a);
  font-size: 0.8rem;
  font-weight: 700;
  transition: var(--transition-fast);
}
.mcq-score-chip i { font-size: 0.75rem; }
.mcq-score-chip.has-score {
  background: rgba(56, 239, 125, 0.12);
  border-color: rgba(56, 239, 125, 0.35);
  color: var(--science-b);
}
@media (max-width: 640px) {
  .mcq-score-chip { margin-left: 0; }
}

/* ═══════════════════════════════════════════════════════════════
   HOMEPAGE REDESIGN — Hero trust chips, ad-free strip,
   why-us grid, steps, mission banner, final CTA
   ═══════════════════════════════════════════════════════════════ */

/* ─── HERO TRUST CHIPS ──────────────────────────────────────────── */
.hero-trust {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: var(--space-sm);
  margin-bottom: var(--space-2xl);
  animation: fadeInUp 0.7s ease 0.35s both;
}
.trust-chip {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 0.4rem 0.9rem;
  border-radius: var(--radius-full);
  background: var(--bg-card);
  box-shadow: var(--shadow-sm);
  border: 1px solid var(--border);
  font-size: 0.78rem;
  font-weight: 600;
  color: var(--text-secondary);
  transition: var(--transition-fast);
}
.trust-chip i { color: var(--accent); font-size: 0.75rem; }
.trust-chip:hover {
  border-color: var(--border-glow);
  color: var(--text-primary);
  transform: translateY(-2px);
}

/* ─── HERO STATS (5-up grid) ───────────────────────────────────── */
.hero-stats {
  grid-template-columns: repeat(5, 1fr);
}
@media (max-width: 900px) {
  .hero-stats { grid-template-columns: repeat(3, 1fr); }
  .hero-stats .stat-card:last-child:nth-child(even) { grid-column: span 1; }
}
@media (max-width: 640px) {
  .hero-stats { grid-template-columns: repeat(2, 1fr); }
  .hero-stats .stat-card:nth-child(5) { grid-column: span 2; }
}

/* ─── AD-FREE TRUST STRIP ──────────────────────────────────────── */
.adfree-strip {
  background: linear-gradient(90deg, #EFF6FF, #F0FDFA, #EFF6FF);
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
  padding: var(--space-md) 0;
}
.adfree-strip-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-md);
  flex-wrap: wrap;
}
.adfree-strip-text {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  font-size: 0.85rem;
  color: var(--text-secondary);
  flex-wrap: wrap;
}
.adfree-strip-text i {
  color: var(--science-b);
  font-size: 1.1rem;
}
.adfree-strip-text strong {
  color: var(--text-primary);
  font-weight: 700;
}
.adfree-strip-text span { opacity: 0.85; }
@media (max-width: 640px) {
  .adfree-strip-text { flex-direction: column; align-items: flex-start; gap: 4px; }
}

/* ─── WHY US GRID ──────────────────────────────────────────────── */
.why-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--space-lg);
}
@media (max-width: 900px) {
  .why-grid { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 640px) {
  .why-grid { grid-template-columns: 1fr; }
}
.why-grid .feature-card {
  position: relative;
  overflow: hidden;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: var(--space-xl);
}
.why-grid .feature-card::before {
  content: '';
  position: absolute;
  top: 0; left: 0; right: 0;
  height: 3px;
  background: var(--grad-primary);
  opacity: 0;
  transition: var(--transition);
}
.why-grid .feature-card:hover::before { opacity: 1; }

/* ─── HOW IT WORKS / STEPS ─────────────────────────────────────── */
.steps-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--space-xl);
}
@media (max-width: 900px) {
  .steps-grid { grid-template-columns: 1fr; max-width: 480px; margin: 0 auto; }
}
.step-card {
  position: relative;
  text-align: center;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: var(--space-2xl) var(--space-lg);
  transition: var(--transition);
}
.step-card:hover {
  border-color: var(--border-glow);
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
}
.step-num {
  position: absolute;
  top: -14px;
  left: 50%;
  transform: translateX(-50%);
  width: 28px;
  height: 28px;
  border-radius: 50%;
  background: var(--accent);
  color: white;
  font-size: 0.8rem;
  font-weight: 800;
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: var(--shadow-sm);
}
.step-icon {
  width: 56px;
  height: 56px;
  margin: 0 auto var(--space-md);
  border-radius: var(--radius-md);
  background: var(--accent-light);
  border: 1px solid #BFDBFE;
  color: var(--accent);
  font-size: 1.4rem;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: var(--transition);
}
.step-card:hover .step-icon {
  background: var(--accent);
  color: white;
  transform: scale(1.05);
}
.step-title { font-size: 1.05rem; font-weight: 700; color: #0F172A; margin-bottom: var(--space-sm); }
.step-desc { font-size: 0.88rem; color: var(--text-secondary); line-height: 1.7; }

/* ─── MISSION BANNER ───────────────────────────────────────────── */
.mission-banner {
  position: relative;
  overflow: hidden;
  background:
    radial-gradient(ellipse 70% 90% at 15% 50%, rgba(29,78,216,0.06) 0%, transparent 60%),
    radial-gradient(ellipse 60% 80% at 85% 30%, rgba(15,118,110,0.04) 0%, transparent 55%),
    #EFF6FF;
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
  padding: var(--space-3xl) 0;
}
.mission-banner-inner {
  display: grid;
  grid-template-columns: 1.4fr 1fr;
  gap: var(--space-2xl);
  align-items: center;
}
@media (max-width: 900px) {
  .mission-banner-inner { grid-template-columns: 1fr; gap: var(--space-xl); text-align: center; }
}
.mission-quote i {
  color: var(--accent);
  font-size: 1.6rem;
  opacity: 0.6;
  display: block;
  margin-bottom: var(--space-sm);
}
.mission-quote p {
  font-family: var(--font-hindi);
  font-size: clamp(1.15rem, 2.5vw, 1.6rem);
  font-weight: 600;
  color: #0F172A;
  line-height: 1.7;
  margin-bottom: var(--space-md);
}
.mission-quote span {
  font-size: 0.85rem;
  color: var(--accent);
  font-weight: 600;
  letter-spacing: 0.5px;
}
.mission-quote {
  display: flex;
  align-items: center;
  gap: var(--space-xl);
}
.mission-quote-text {
  flex: 1;
}
.teacher-avatar-wrap {
  position: relative;
  flex-shrink: 0;
  width: 120px;
  height: 120px;
}
.teacher-avatar {
  width: 100%;
  height: 100%;
  border-radius: 50%;
  object-fit: cover;
  border: 4px solid #fff;
  box-shadow: 0 4px 24px rgba(29,78,216,0.18), 0 0 0 2px rgba(29,78,216,0.12);
  position: relative;
  z-index: 1;
  transition: transform 0.3s ease, box-shadow 0.3s ease;
}
.teacher-avatar:hover {
  transform: scale(1.05);
  box-shadow: 0 8px 32px rgba(29,78,216,0.25), 0 0 0 3px rgba(29,78,216,0.18);
}
.teacher-avatar-ring {
  position: absolute;
  inset: -4px;
  border-radius: 50%;
  border: 3px solid transparent;
  background: linear-gradient(135deg, var(--accent), var(--success)) border-box;
  -webkit-mask: linear-gradient(#fff 0 0) padding-box, linear-gradient(#fff 0 0);
  -webkit-mask-composite: xor;
  mask-composite: exclude;
  animation: ring-spin 4s linear infinite;
}
@keyframes ring-spin {
  0% { transform: rotate(0deg); }
  100% { transform: rotate(360deg); }
}
@media (max-width: 640px) {
  .mission-quote { flex-direction: column; text-align: center; }
  .teacher-avatar-wrap { width: 100px; height: 100px; }
}
.mission-stats {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--space-md);
}
@media (max-width: 640px) {
  .mission-stats { grid-template-columns: 1fr; }
}
.mission-stat {
  text-align: center;
  background: var(--bg-card);
  box-shadow: var(--shadow-sm);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: var(--space-lg) var(--space-sm);
  transition: var(--transition);
}
.mission-stat:hover { border-color: var(--border-glow); transform: translateY(-2px); }
.mission-stat-num {
  font-size: 1.5rem;
  font-weight: 800;
  color: var(--accent);
  line-height: 1.2;
}
.mission-stat-label {
  font-size: 0.7rem;
  color: var(--text-muted);
  margin-top: var(--space-xs);
  font-weight: 500;
}

/* ─── FINAL CTA ────────────────────────────────────────────────── */
.final-cta-section { padding-top: 0; }
.final-cta {
  position: relative;
  overflow: hidden;
  text-align: center;
  background:
    radial-gradient(ellipse 60% 100% at 50% 0%, rgba(29,78,216,0.06) 0%, transparent 60%),
    var(--bg-card);
  border: 1px solid var(--border-glow);
  border-radius: var(--radius-xl);
  padding: var(--space-3xl) var(--space-xl);
  box-shadow: var(--shadow-lg);
}
.final-cta h2 {
  font-family: var(--font-hindi);
  font-size: clamp(1.5rem, 3.5vw, 2.2rem);
  font-weight: 800;
  margin-bottom: var(--space-md);
  color: #0F172A;
}
.final-cta p {
  color: var(--text-secondary);
  max-width: 620px;
  margin: 0 auto var(--space-xl);
  font-size: 0.95rem;
  line-height: 1.8;
}
.final-cta-actions {
  display: flex;
  gap: var(--space-md);
  justify-content: center;
  flex-wrap: wrap;
}

/* ─── BUTTON SIZES ─────────────────────────────────────────────── */
.btn-lg {
  padding: 0.9rem 2.2rem;
  font-size: 1rem;
}

/* ─── SECTION DESC ─────────────────────────────────────────────── */
.section-desc {
  color: var(--text-muted);
  font-size: 0.9rem;
  max-width: 560px;
  margin: var(--space-md) auto 0;
  line-height: 1.7;
}

/* ─── COMING SOON CARD ────────────────────────────────────────── */
.subject-card.coming-soon-card {
  opacity: 0.72;
  border-style: dashed;
  background: var(--bg-card, #fff);
  cursor: default;
  pointer-events: none;
  filter: saturate(0.35);
}
.subject-card.coming-soon-card:hover {
  transform: none;
  box-shadow: none;
}

/* ═══════════════════════════════════════════════════════════════
   MOBILE-FIRST PERF & RESPONSIVE ENHANCEMENTS
   ═══════════════════════════════════════════════════════════════ */

/* Mobile URL-bar friendly heights (svh/dvh with vh fallback) */
.hero {
  min-height: calc(100vh - var(--header-height));
  min-height: calc(100svh - var(--header-height));
}
.mobile-menu {
  height: 100vh;
  height: 100dvh;
}

/* Tap highlight + momentum scroll for smoother mobile feel */
html {
  -webkit-tap-highlight-color: transparent;
}
body {
  -webkit-overflow-scrolling: touch;
  overscroll-behavior-y: contain;
}

/* Tables inside notes overflow gracefully (notes use <table> a lot) */
.notes-body table,
.notes-section table,
.ch-main table {
  display: block;
  width: 100%;
  max-width: 100%;
  overflow-x: auto;
  white-space: nowrap;
  -webkit-overflow-scrolling: touch;
}

/* Long words / formulas never blow the layout */
.notes-body,
.notes-section,
.qa-answer,
.mcq-explanation,
.search-result-title,
.ch-main p {
  overflow-wrap: break-word;
  word-break: break-word;
}

/* ─── ≤ 900px ─────────────────────────────────────────────────── */
@media (max-width: 900px) {
  .page-hero { padding: var(--space-xl) 0; }
  .page-hero-title { font-size: 1.6rem; }
  .ch-hero-title { font-size: 1.3rem; }
  .ch-main .notes-section { padding: var(--space-lg); }
  .qa-item, .mcq-card { padding: var(--space-md); }
}

/* ─── ≤ 768px ─────────────────────────────────────────────────── */
@media (max-width: 768px) {
  .footer-links { flex-wrap: wrap; gap: var(--space-xl) var(--space-xl); }
  .footer-col { flex: 1 1 130px; }
  .breadcrumb { flex-wrap: wrap; row-gap: var(--space-xs); }
  .breadcrumb-sep { display: none; }
  .hero-actions .btn { width: auto; }
  .announcement-text { font-size: 0.78rem; line-height: 1.4; }
  .announcement-inner { padding: 0.4rem var(--space-lg); gap: var(--space-xs); }
  .ch-prev-next { gap: var(--space-sm); }
  .notes-body { font-size: 0.92rem; line-height: 1.9; }
}

/* ─── ≤ 640px ─────────────────────────────────────────────────── */
@media (max-width: 640px) {
  .container { padding: 0 var(--space-md); }
  .hero-content { padding: 0 var(--space-sm); }
  .hero-title { font-size: clamp(1.6rem, 7vw, 2.2rem); }
  .hero-subtitle { font-size: 0.92rem; }
  .hero-badge { font-size: 0.72rem; padding: 0.3rem 0.8rem; }
  .trust-chip { font-size: 0.7rem; padding: 0.32rem 0.7rem; }
  .section-title { font-size: 1.25rem; }
  .final-cta-actions { flex-direction: column; align-items: stretch; }
  .final-cta-actions .btn-lg { width: 100%; }
  .adfree-strip-inner { justify-content: center; text-align: center; }
  .mission-banner { padding: var(--space-2xl) 0; }
  .mission-quote p { font-size: 1.05rem; }
  .subject-card { padding: var(--space-md); }
  .page-hero-meta { font-size: 0.75rem; gap: var(--space-sm); }
  .search-overlay { padding: var(--space-lg) var(--space-md); }
  .search-input { font-size: 0.95rem; }
  .ch-layout { gap: var(--space-md); }
  .ch-main { padding: var(--space-md) 0; }
  .mcq-options { gap: var(--space-sm); }
}

/* ─── ≤ 480px ─────────────────────────────────────────────────── */
@media (max-width: 480px) {
  .mobile-menu { width: 86vw; max-width: 320px; }
  .hero-stats { gap: var(--space-xs); }
  .stat-card { padding: var(--space-sm) var(--space-xs); }
  .stat-label { font-size: 0.62rem; }
  .class-card { padding: var(--space-lg); }
  .ch-hero-inner { padding: var(--space-md); }
  .ch-hero-meta { flex-wrap: wrap; gap: var(--space-xs); }
  .ch-hero-meta span { font-size: 0.7rem; }
  .ch-nav-wrapper { top: 48px; }
  .book-nav-bar { top: 48px; }
  .qa-question { font-size: 0.9rem; }
  .mcq-q { font-size: 0.9rem; }
  .continue-reading-card { padding: var(--space-md); gap: var(--space-sm); }
  .continue-reading-title { font-size: 0.95rem; }
  .continue-reading-btn { display: none; }
  .footer-bottom p { font-size: 0.72rem; text-align: center; padding: 0 var(--space-sm); }
}

/* ─── ≤ 380px (very small phones) ─────────────────────────────── */
@media (max-width: 380px) {
  .hero-stats { grid-template-columns: repeat(2, 1fr); }
  .hero-stats .stat-card:nth-child(5) { grid-column: span 2; }
  .nav-actions { gap: var(--space-xs); }
  .lang-toggle-btn span { display: none; }
  .lang-toggle-btn { padding: 0.45rem; }
  .steps-grid { max-width: 100%; }
  .why-grid { gap: var(--space-md); }
  .notes-section, .qa-item, .mcq-card { padding: var(--space-sm); }
  .section { padding: var(--space-xl) 0; }
}

/* ═══════════════════════════════════════════════════════════════
/* ═══════════════════════════════════════════════════════════════
   QUIZ SYSTEM — Online Test (student) + Teacher Area
   ═══════════════════════════════════════════════════════════════ */

.quiz-loading { text-align: center; padding: var(--space-3xl) 0; color: var(--text-muted); }
.quiz-loading p { margin-top: var(--space-md); }
.quiz-error {
  text-align: center; padding: var(--space-3xl) var(--space-lg);
  color: var(--danger); border: 1px dashed var(--danger);
  border-radius: var(--radius-lg); margin: var(--space-xl) 0;
}
.quiz-error i { font-size: 2rem; display: block; margin-bottom: var(--space-sm); }
.quiz-empty { text-align: center; padding: var(--space-3xl) 0; color: var(--text-muted); }
.quiz-empty i { font-size: 2.5rem; display: block; margin-bottom: var(--space-md); opacity: 0.4; }

/* ─── Filter bar ─────────────────────────────────────────────── */
.quiz-filter-bar { display: flex; gap: var(--space-md); margin-bottom: var(--space-xl); flex-wrap: wrap; }
.quiz-filter-bar select {
  background: var(--bg-card); color: var(--text-primary);
  border: 1px solid var(--border); border-radius: var(--radius-md);
  padding: 0.6rem 1rem; font-size: 0.85rem; font-family: inherit;
  min-width: 160px;
}

/* ─── Quiz grid + cards ──────────────────────────────────────── */
.quiz-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(260px, 1fr)); gap: var(--space-lg); }
.quiz-card {
  display: block; background: var(--bg-card); border: 1px solid var(--border);
  border-radius: var(--radius-lg); padding: var(--space-lg);
  transition: var(--transition); text-decoration: none;
}
.quiz-card:hover { transform: translateY(-4px); border-color: var(--border-glow); box-shadow: var(--shadow-md); }
.quiz-card-head { display: flex; gap: var(--space-xs); margin-bottom: var(--space-md); flex-wrap: wrap; }
.quiz-card-title { font-size: 1.05rem; font-weight: 700; margin-bottom: var(--space-xs); }
.quiz-card-desc { font-size: 0.82rem; color: var(--text-secondary); line-height: 1.6; margin-bottom: var(--space-md); }
.quiz-card-meta { display: flex; gap: var(--space-md); font-size: 0.75rem; color: var(--text-muted); flex-wrap: wrap; }
.quiz-card-meta span { display: inline-flex; align-items: center; gap: 4px; }

/* ─── Quiz entry ─────────────────────────────────────────────── */
.quiz-entry-card {
  max-width: 620px; margin: 0 auto; background: var(--bg-card);
  border: 1px solid var(--border-glow); border-radius: var(--radius-xl);
  padding: var(--space-2xl); box-shadow: var(--shadow-lg);
}
.quiz-entry-head { display: flex; gap: var(--space-xs); margin-bottom: var(--space-md); }
.quiz-entry-card h2 { font-size: 1.4rem; margin-bottom: var(--space-sm); }
.quiz-entry-desc { color: var(--text-secondary); font-size: 0.9rem; line-height: 1.7; margin-bottom: var(--space-lg); }
.quiz-info-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(110px, 1fr)); gap: var(--space-sm); margin-bottom: var(--space-2xl); }
.quiz-info { text-align: center; padding: var(--space-md); background: var(--bg-card2); border: 1px solid var(--border); border-radius: var(--radius-md); }
.quiz-info i { font-size: 1.1rem; color: var(--accent); display: block; margin-bottom: 4px; }
.quiz-info span { font-weight: 700; font-size: 1rem; display: block; }
.quiz-info small { color: var(--text-muted); font-size: 0.7rem; }
.quiz-entry-form h3 { font-size: 1rem; margin-bottom: var(--space-lg); }
.quiz-entry-form label { display: block; font-size: 0.8rem; font-weight: 600; margin-bottom: var(--space-md); color: var(--text-secondary); }
.quiz-entry-form input {
  display: block; width: 100%; margin-top: 6px; background: var(--bg-primary);
  border: 1px solid var(--border); color: var(--text-primary);
  border-radius: var(--radius-md); padding: 0.7rem 1rem; font-size: 0.9rem; font-family: inherit;
}
.quiz-entry-form input:focus { outline: none; border-color: var(--accent); }
.quiz-entry-row { display: grid; grid-template-columns: 1fr 1fr; gap: var(--space-md); }
.quiz-warn { font-size: 0.78rem; color: var(--english-b); margin-bottom: var(--space-lg); }
.btn-block { width: 100%; }

/* ─── Attempt page ───────────────────────────────────────────── */
.quiz-attempt-top {
  display: flex; justify-content: space-between; align-items: center; gap: var(--space-md);
  flex-wrap: wrap; margin-bottom: var(--space-xl);
}
.quiz-attempt-title h2 { font-size: 1.2rem; margin-bottom: 4px; }
.quiz-attempt-student { font-size: 0.8rem; color: var(--text-muted); }
.quiz-timer {
  display: inline-flex; align-items: center; gap: 8px;
  background: var(--danger-bg); border: 1px solid #FECACA;
  color: var(--danger-text); font-weight: 700; font-size: 1.1rem;
  padding: 0.5rem 1.1rem; border-radius: var(--radius-full); font-variant-numeric: tabular-nums;
}
.quiz-attempt-body { display: grid; grid-template-columns: 1fr 220px; gap: var(--space-xl); align-items: start; }
@media (max-width: 768px) { .quiz-attempt-body { grid-template-columns: 1fr; } }
.quiz-question-panel {
  background: var(--bg-card); border: 1px solid var(--border);
  border-radius: var(--radius-lg); padding: var(--space-xl);
}
.quiz-q-meta { display: flex; gap: var(--space-xs); margin-bottom: var(--space-lg); }
.quiz-q-text { font-size: 1.05rem; font-weight: 600; line-height: 1.7; margin-bottom: var(--space-xl); }
.quiz-q-options { display: flex; flex-direction: column; gap: var(--space-sm); margin-bottom: var(--space-xl); }
/* Attempt screen only — anti-copy deterrent on question/option text.
   DETERRENT ONLY: screenshots / DevTools / page source bypass this; it slows
   casual copying, it does not stop determined cheating. The short-answer
   textarea (student's own answer box) is exempt so answers stay selectable
   and paste-able. Scoped via #quiz-q-* ids, which exist only on the timed
   attempt screen — result/review, teacher dashboard and builder are untouched. */
#quiz-q-text, #quiz-q-options { user-select: none; -webkit-user-select: none; -moz-user-select: none; }
#quiz-q-options .quiz-short-answer { user-select: text; -webkit-user-select: text; }
.quiz-option {
  display: flex; align-items: center; gap: var(--space-md); width: 100%; text-align: left;
  background: #FFFFFF; border: 1.5px solid #D1D5DB; color: var(--text-primary);
  border-radius: var(--radius-md); padding: 0.85rem 1rem; font-size: 0.9rem; font-family: inherit;
  cursor: pointer; transition: var(--transition-fast);
}
.quiz-option:hover { border-color: var(--border-glow); }
.quiz-option.selected { border-color: var(--accent); background: rgba(38,208,206,0.12); }
.quiz-option-letter {
  width: 26px; height: 26px; border-radius: 50%; flex-shrink: 0;
  background: #F1F5F9; border: 1.5px solid #D1D5DB; color: var(--text-secondary); display: flex; align-items: center; justify-content: center;
  font-size: 0.75rem; font-weight: 700;
}
.quiz-option.selected .quiz-option-letter { background: var(--accent); color: white; }
.quiz-option-hint { font-size: 0.72rem; color: var(--text-muted); }
.quiz-short-answer {
  width: 100%; min-height: 120px; background: var(--bg-primary); color: var(--text-primary);
  border: 1px solid var(--border); border-radius: var(--radius-md);
  padding: 0.9rem 1rem; font-size: 0.9rem; font-family: inherit; resize: vertical;
}
.quiz-short-answer:focus { outline: none; border-color: var(--accent); }
.quiz-attempt-nav { display: flex; gap: var(--space-sm); flex-wrap: wrap; }
.quiz-attempt-nav .btn:first-child { margin-right: auto; }

/* ─── Palette ────────────────────────────────────────────────── */
.quiz-palette {
  background: var(--bg-card); border: 1px solid var(--border);
  border-radius: var(--radius-lg); padding: var(--space-lg);
  position: sticky; top: calc(var(--header-height) + var(--space-md));
}
.quiz-palette h4 { font-size: 0.9rem; margin-bottom: var(--space-md); }
.quiz-palette-grid { display: grid; grid-template-columns: repeat(5, 1fr); gap: 6px; margin-bottom: var(--space-lg); }
.pal-btn {
  aspect-ratio: 1; border-radius: var(--radius-sm); border: 1px solid var(--border);
  background: var(--bg-card2); color: var(--text-secondary); font-size: 0.75rem; font-weight: 600;
  cursor: pointer; transition: var(--transition-fast);
}
.pal-btn.answered { background: var(--success); border-color: var(--success); color: white; }
.pal-btn.current { border-color: var(--accent); box-shadow: 0 0 0 2px rgba(38,208,206,0.35); }
.quiz-palette-legend { display: flex; flex-direction: column; gap: 6px; font-size: 0.72rem; color: var(--text-muted); }
.quiz-palette-legend span { display: inline-flex; align-items: center; gap: 6px; }
.pal-dot { width: 12px; height: 12px; border-radius: 3px; background: var(--bg-card2); border: 1px solid var(--border); display: inline-block; }
.pal-dot.answered { background: var(--success); border-color: var(--success); }
.pal-dot.current { border-color: var(--accent); }

/* ─── Result page ────────────────────────────────────────────── */
.quiz-result { max-width: 720px; margin: 0 auto; text-align: center; }
.quiz-result-badge {
  width: 84px; height: 84px; border-radius: 50%; margin: 0 auto var(--space-lg);
  display: flex; align-items: center; justify-content: center; font-size: 2.2rem;
  background: var(--grad-primary); color: white; box-shadow: var(--shadow-lg);
}
.quiz-result h2 { font-size: 1.5rem; margin-bottom: var(--space-xs); }
.quiz-result-quiz { color: var(--text-muted); margin-bottom: var(--space-2xl); }
.quiz-score-ring {
  --pct: 0;
  width: 170px; height: 170px; margin: 0 auto var(--space-2xl); border-radius: 50%;
  background: conic-gradient(var(--accent) calc(var(--pct) * 1%), rgba(255,255,255,0.08) 0);
  display: flex; align-items: center; justify-content: center;
}
.quiz-score-inner {
  width: 138px; height: 138px; border-radius: 50%; background: var(--bg-card);
  display: flex; flex-direction: column; align-items: center; justify-content: center; gap: 2px;
}
.quiz-score-big { font-size: 1.4rem; font-weight: 800; }
.quiz-score-pct { font-size: 1rem; font-weight: 700; color: var(--accent); }
.quiz-score-grade { font-size: 0.75rem; color: var(--text-muted); }
.quiz-result-stats {
  display: grid; grid-template-columns: repeat(auto-fit, minmax(120px, 1fr));
  gap: var(--space-sm); margin-bottom: var(--space-2xl);
}
.quiz-result-stats > div { background: var(--bg-card); border: 1px solid var(--border); border-radius: var(--radius-md); padding: var(--space-md); }
.quiz-result-stats i { display: block; color: var(--accent); font-size: 1rem; margin-bottom: 4px; }
.quiz-result-stats span { font-weight: 600; font-size: 0.9rem; display: block; }
.quiz-result-stats small { color: var(--text-muted); font-size: 0.7rem; }
.quiz-result-actions { display: flex; gap: var(--space-sm); justify-content: center; flex-wrap: wrap; margin-bottom: var(--space-2xl); }

/* ─── Leaderboard ────────────────────────────────────────────── */
.quiz-result-lb { max-width: 720px; margin: 0 auto var(--space-2xl); text-align: left; }
.quiz-lb-loading { padding: var(--space-lg) 0; text-align: center; color: var(--text-muted); font-size: 0.85rem; }
.quiz-lb-empty { text-align: center; color: var(--text-muted); padding: var(--space-lg); font-size: 0.85rem; }
.quiz-lb-head {
  display: flex; align-items: center; gap: var(--space-sm); flex-wrap: wrap;
  font-size: 1rem; font-weight: 700; margin-bottom: var(--space-md);
}
.quiz-lb-head i { color: #f7971e; }
.quiz-lb-head .chip { margin-left: auto; }
.quiz-lb { min-width: 560px; }
.quiz-lb td.lb-rank { font-weight: 700; white-space: nowrap; color: #0F172A; }
.quiz-lb tr.lb-mine td { background: var(--accent-light); }
.quiz-lb tr.lb-mine td:first-child { border-left: 3px solid var(--accent); }
.quiz-review { text-align: left; background: var(--bg-card); border: 1px solid var(--border); border-radius: var(--radius-lg); padding: var(--space-xl); }
.quiz-review h3 { font-size: 1rem; margin-bottom: var(--space-lg); }
.review-item { border: 1px solid var(--border); border-radius: var(--radius-md); padding: var(--space-md); margin-bottom: var(--space-sm); background: var(--bg-card); box-shadow: var(--shadow-sm); }
.review-item.right { border-color: rgba(56,239,125,0.4); }
.review-item.wrong { border-color: rgba(204,43,94,0.4); }
.review-q { font-weight: 600; font-size: 0.9rem; line-height: 1.6; margin-bottom: var(--space-sm); color: #0F172A; }
.review-mark { float: right; font-size: 1rem; }
.review-mark.right { color: var(--success); }
.review-mark.wrong { color: var(--danger); }
.review-opts { display: flex; flex-direction: column; gap: 4px; }
.review-opt { font-size: 0.82rem; padding: 4px 8px; border-radius: var(--radius-sm); color: var(--text-secondary); }
.review-opt.correct { color: var(--success); background: rgba(56,239,125,0.1); }
.review-opt.wrong { color: var(--danger); background: rgba(204,43,94,0.1); }
.review-exp { margin-top: var(--space-sm); font-size: 0.8rem; color: var(--english-b); }

/* ─── Teacher login ──────────────────────────────────────────── */
.teacher-login-card { max-width: 420px; margin: 0 auto; text-align: center; background: var(--bg-card); border: 1px solid var(--border-glow); border-radius: var(--radius-xl); padding: var(--space-2xl); box-shadow: var(--shadow-lg); }
.teacher-login-icon { width: 64px; height: 64px; border-radius: 50%; margin: 0 auto var(--space-lg); background: var(--grad-primary); color: white; display: flex; align-items: center; justify-content: center; font-size: 1.5rem; }
.teacher-login-card h2 { margin-bottom: var(--space-sm); }
.quiz-input {
  width: 100%; background: var(--bg-primary); color: var(--text-primary);
  border: 1px solid var(--border); border-radius: var(--radius-md);
  padding: 0.7rem 1rem; font-size: 0.9rem; font-family: inherit; margin-bottom: var(--space-md);
}
.quiz-input:focus { outline: none; border-color: var(--accent); }
.quiz-input-sm { width: 80px; display: inline-block; margin-bottom: 0; }
.teacher-hint { font-size: 0.75rem; color: var(--text-muted); margin: var(--space-md) 0; }

/* ─── Teacher toolbar + stats ────────────────────────────────── */
.teacher-toolbar { display: flex; align-items: center; gap: var(--space-sm); flex-wrap: wrap; margin-bottom: var(--space-xl); }
.teacher-toolbar .subs-title { margin-right: auto; }
.teacher-stats { display: grid; grid-template-columns: repeat(auto-fit, minmax(150px, 1fr)); gap: var(--space-md); margin-bottom: var(--space-2xl); }
.tstat { text-align: center; background: var(--bg-card); border: 1px solid var(--border); border-radius: var(--radius-md); padding: var(--space-lg); }
.tstat i { font-size: 1.3rem; color: var(--accent); display: block; margin-bottom: 6px; }
.tstat span { font-size: 1.5rem; font-weight: 800; display: block; }
.tstat small { color: var(--text-muted); font-size: 0.75rem; }

/* ─── Teacher quiz list ──────────────────────────────────────── */
.teacher-quiz-list h3 { font-size: 1.05rem; margin-bottom: var(--space-lg); }
.tquiz { display: flex; justify-content: space-between; align-items: center; gap: var(--space-md); flex-wrap: wrap; background: var(--bg-card); border: 1px solid var(--border); border-radius: var(--radius-md); padding: var(--space-md) var(--space-lg); margin-bottom: var(--space-sm); }
.tquiz-main h4 { font-size: 0.95rem; margin: 6px 0 2px; }
.tquiz-meta { font-size: 0.75rem; color: var(--text-muted); }
.tquiz-side { display: flex; align-items: center; gap: var(--space-md); flex-wrap: wrap; }
.tquiz-subs { font-weight: 700; font-size: 0.85rem; }
.tquiz-best { font-size: 0.75rem; color: var(--success); }
.tquiz-actions { display: flex; gap: 6px; }

/* ─── Teacher: roll-anomalies audit panel (one-attempt lock) ── */
.teacher-anomalies { margin-top: var(--space-2xl); background: var(--bg-card); border: 1px solid var(--border); border-radius: var(--radius-lg); padding: var(--space-lg); }
.teacher-anomalies h3 { font-size: 1.02rem; margin-bottom: var(--space-md); display: flex; align-items: center; gap: 8px; flex-wrap: wrap; }
.teacher-anomalies h3 i { color: var(--accent); }
.anom-group { margin-top: var(--space-md); }
.anom-group h4 { font-size: 0.85rem; color: var(--text-secondary); margin-bottom: var(--space-sm); display: flex; align-items: center; gap: 6px; }
.anom-group h4 i { color: var(--danger); }
.anom-card { border: 1px solid var(--border); border-radius: var(--radius-md); padding: var(--space-md); margin-bottom: var(--space-sm); }
.anom-card-head { display: flex; align-items: center; gap: var(--space-sm); flex-wrap: wrap; margin-bottom: var(--space-sm); }
.anom-badge { font-weight: 800; font-size: 0.85rem; padding: 2px 8px; border-radius: var(--radius-sm); }
.anom-badge-dup { background: rgba(255,107,107,0.15); color: var(--danger); }
.anom-entries { display: flex; flex-direction: column; }
.anom-entry { display: flex; gap: var(--space-md); justify-content: space-between; flex-wrap: wrap; font-size: 0.82rem; padding: 5px 0; border-top: 1px dashed var(--border); }
.anom-entry:first-child { border-top: none; }
.anom-entry span { color: var(--text-secondary); }
.anom-entry span:first-child { font-weight: 600; color: var(--text-primary); }

/* ─── Quiz builder ───────────────────────────────────────────── */
.builder-wrap { max-width: 860px; margin: 0 auto; }
.builder-basic { background: var(--bg-card); border: 1px solid var(--border); border-radius: var(--radius-lg); padding: var(--space-xl); margin-bottom: var(--space-xl); }
.builder-row { display: grid; grid-template-columns: 2fr 1fr 1fr; gap: var(--space-md); margin-bottom: var(--space-md); }
.builder-row:last-child { margin-bottom: 0; }
@media (max-width: 640px) { .builder-row { grid-template-columns: 1fr; } }
.builder-row label { display: block; font-size: 0.78rem; font-weight: 600; color: var(--text-secondary); }
.builder-row .quiz-input { margin-bottom: 0; }
.builder-questions-head { display: flex; justify-content: space-between; align-items: center; gap: var(--space-sm); flex-wrap: wrap; margin-bottom: var(--space-md); }
.builder-q { background: var(--bg-card); border: 1px solid var(--border); border-radius: var(--radius-lg); padding: var(--space-lg); margin-bottom: var(--space-md); }
.builder-q-head { margin-bottom: var(--space-md); }
.builder-q-field label, .builder-q-opts label { display: block; font-size: 0.78rem; font-weight: 600; color: var(--text-secondary); margin-bottom: 6px; }
.builder-q-field .quiz-input { margin-bottom: var(--space-sm); }
.builder-q-opts { margin: var(--space-md) 0; }
.builder-q-opt { display: flex; align-items: center; gap: 6px; margin-bottom: 6px; padding: 6px; border: 1px solid var(--border); border-radius: var(--radius-sm); cursor: pointer; transition: var(--transition-fast); }
.builder-q-opt.correct { border-color: var(--success); background: rgba(56,239,125,0.08); }
.builder-q-opt .opt-letter { width: 24px; height: 24px; border-radius: 50%; background: var(--bg-card2); border: 1px solid var(--border); display: flex; align-items: center; justify-content: center; font-size: 0.7rem; font-weight: 700; flex-shrink: 0; }
.builder-q-opt.correct .opt-letter { background: var(--success); color: white; border-color: var(--success); }
.builder-q-opt .quiz-input { margin-bottom: 0; flex: 1; }
.opt-del { background: none; border: none; color: var(--danger); cursor: pointer; font-size: 0.85rem; padding: 4px; }
.builder-q-row { display: flex; align-items: flex-end; gap: var(--space-sm); flex-wrap: wrap; margin-top: var(--space-md); }
.builder-q-exp { margin-top: var(--space-sm); }
.builder-save { display: flex; gap: var(--space-sm); flex-wrap: wrap; justify-content: flex-end; margin-top: var(--space-xl); }

/* ─── Submissions table ──────────────────────────────────────── */
.subs-table-wrap { overflow-x: auto; background: var(--bg-card); border: 1px solid var(--border); border-radius: var(--radius-lg); }
.subs-table { width: 100%; border-collapse: collapse; font-size: 0.82rem; min-width: 640px; }
.subs-table th { text-align: left; padding: 0.8rem 1rem; background: var(--bg-card2); color: var(--text-muted); font-size: 0.72rem; text-transform: uppercase; letter-spacing: 0.5px; border-bottom: 1px solid var(--border); }
.subs-table td { padding: 0.7rem 1rem; border-bottom: 1px solid var(--border); }
.subs-table tr:last-child td { border-bottom: none; }
.subs-table tr:hover td { background: var(--bg-card2); }

/* ─── Quiz responsive ────────────────────────────────────────── */
@media (max-width: 640px) {
  .quiz-entry-row { grid-template-columns: 1fr; }
  .quiz-attempt-top { flex-direction: column; align-items: flex-start; }
  .quiz-question-panel { padding: var(--space-lg); }
  .quiz-result-stats { grid-template-columns: 1fr 1fr; }
  .tquiz { flex-direction: column; align-items: flex-start; }
  .tquiz-side { width: 100%; justify-content: space-between; }
  .builder-q-opt { flex-wrap: wrap; }
}

/* ─── IMAGE LIGHTBOX ───────────────────────────────────────── */
.lightbox-overlay {
  position: fixed;
  inset: 0;
  z-index: 9999;
  background: rgba(0, 0, 0, 0.88);
  display: flex;
  align-items: center;
  justify-content: center;
  opacity: 0;
  visibility: hidden;
  transition: opacity 0.3s ease, visibility 0.3s ease;
  backdrop-filter: blur(6px);
  -webkit-backdrop-filter: blur(6px);
}
.lightbox-overlay.active {
  opacity: 1;
  visibility: visible;
}
.lightbox-close {
  position: absolute;
  top: 16px;
  right: 20px;
  width: 44px;
  height: 44px;
  border-radius: 50%;
  border: none;
  background: rgba(255, 255, 255, 0.15);
  color: #fff;
  font-size: 1.3rem;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: background 0.2s, transform 0.2s;
  z-index: 10;
}
.lightbox-close:hover {
  background: rgba(255, 255, 255, 0.3);
  transform: scale(1.1);
}
.lightbox-content {
  display: flex;
  flex-direction: column;
  align-items: center;
  max-width: 90vw;
  max-height: 90vh;
}
.lightbox-img {
  max-width: 90vw;
  max-height: 82vh;
  border-radius: var(--radius-lg);
  box-shadow: 0 8px 60px rgba(0, 0, 0, 0.5);
  object-fit: contain;
  transition: transform 0.3s ease;
}
.lightbox-caption {
  margin-top: var(--space-md);
  color: rgba(255, 255, 255, 0.85);
  font-size: 0.95rem;
  font-weight: 600;
  text-align: center;
  max-width: 80vw;
}
@media (max-width: 640px) {
  .lightbox-img { max-width: 95vw; max-height: 75vh; border-radius: var(--radius-md); }
  .lightbox-close { top: 10px; right: 10px; width: 40px; height: 40px; }
}