/* ═══════════════════════════════════════════════════════════════════
   APPLIED PHYSICS-II EXAM INTELLIGENCE SYSTEM
   Design: Indigo Ink × Volcanic Accent
   Fonts: Syne (display) + Plus Jakarta Sans (body) + JetBrains Mono (code)
═══════════════════════════════════════════════════════════════════ */

/* ── CSS VARIABLES ── */
:root {
  --bg-primary: #0D0B1A;
  --bg-secondary: #13102A;
  --bg-card: #1A1635;
  --bg-card-hover: #201C42;
  --bg-sidebar: #100E22;
  --border: rgba(123, 104, 238, 0.15);
  --border-strong: rgba(123, 104, 238, 0.3);

  --text-primary: #E8E0F0;
  --text-secondary: #A89CC8;
  --text-muted: #6B5F8A;
  --text-accent: #9B8FFF;

  --accent-purple: #7B68EE;
  --accent-violet: #9B8FFF;
  --accent-pink: #E040FB;
  --accent-cyan: #00E5FF;
  --accent-orange: #FF6B2B;
  --accent-green: #69FF47;
  --accent-yellow: #FFD740;

  --u1-color: #7B68EE;
  --u2-color: #E040FB;
  --u3-color: #00BCD4;
  --u4-color: #FF6B2B;

  --critical-color: #FF4757;
  --high-color: #FFA502;
  --medium-color: #2ED573;
  --low-color: #747D8C;

  --sidebar-width: 270px;
  --topbar-height: 64px;
  --radius: 12px;
  --radius-lg: 18px;
  --radius-xl: 24px;

  --shadow-sm: 0 2px 8px rgba(0,0,0,0.3);
  --shadow-md: 0 4px 20px rgba(0,0,0,0.4);
  --shadow-lg: 0 8px 40px rgba(0,0,0,0.5);
  --shadow-glow: 0 0 30px rgba(123, 104, 238, 0.2);

  --transition: 0.25s cubic-bezier(0.4, 0, 0.2, 1);
}

[data-theme="light"] {
  --bg-primary: #F4F2FF;
  --bg-secondary: #EAE7FF;
  --bg-card: #FFFFFF;
  --bg-card-hover: #F0EDFF;
  --bg-sidebar: #1B0A3C;
  --border: rgba(123, 104, 238, 0.2);
  --border-strong: rgba(123, 104, 238, 0.4);
  --text-primary: #1B0A3C;
  --text-secondary: #4A3570;
  --text-muted: #8B7AAA;
  --text-accent: #5B4FCC;
  --shadow-sm: 0 2px 8px rgba(27,10,60,0.08);
  --shadow-md: 0 4px 20px rgba(27,10,60,0.12);
  --shadow-lg: 0 8px 40px rgba(27,10,60,0.15);
  --shadow-glow: 0 0 30px rgba(123, 104, 238, 0.15);
}

/* ── RESET & BASE ── */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

html { scroll-behavior: smooth; font-size: 16px; }

body {
  font-family: 'Plus Jakarta Sans', sans-serif;
  background: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.6;
  overflow-x: hidden;
  transition: background var(--transition), color var(--transition);
}

/* ── SCROLLBAR ── */
::-webkit-scrollbar { width: 6px; height: 6px; }
::-webkit-scrollbar-track { background: var(--bg-secondary); }
::-webkit-scrollbar-thumb { background: var(--accent-purple); border-radius: 3px; }

/* ══════════════════════════════════════════════════════════════════
   SIDEBAR
══════════════════════════════════════════════════════════════════ */
.sidebar {
  position: fixed;
  top: 0; left: 0;
  width: var(--sidebar-width);
  height: 100vh;
  background: var(--bg-sidebar);
  border-right: 1px solid var(--border);
  display: flex;
  flex-direction: column;
  z-index: 1000;
  overflow-y: auto;
  transition: transform var(--transition);
}

.sidebar-header {
  padding: 20px 20px 16px;
  border-bottom: 1px solid var(--border);
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-shrink: 0;
}

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

.logo-icon {
  font-size: 28px;
  filter: drop-shadow(0 0 8px rgba(123,104,238,0.6));
  animation: pulse-glow 3s ease-in-out infinite;
}

@keyframes pulse-glow {
  0%, 100% { filter: drop-shadow(0 0 8px rgba(123,104,238,0.6)); }
  50% { filter: drop-shadow(0 0 16px rgba(155,143,255,0.9)); }
}

.logo-title {
  font-family: 'Syne', sans-serif;
  font-weight: 800;
  font-size: 1.1rem;
  color: var(--text-primary);
  letter-spacing: -0.02em;
}

.logo-sub {
  font-size: 0.65rem;
  color: var(--text-muted);
  font-weight: 500;
  letter-spacing: 0.05em;
}

.sidebar-close {
  display: none;
  background: none;
  border: none;
  color: var(--text-muted);
  font-size: 1.1rem;
  cursor: pointer;
  padding: 4px 8px;
  border-radius: 6px;
  transition: all var(--transition);
}

.sidebar-close:hover { background: var(--border); color: var(--text-primary); }

.nav-section-label {
  padding: 16px 20px 6px;
  font-size: 0.6rem;
  font-weight: 700;
  letter-spacing: 0.12em;
  color: var(--text-muted);
  text-transform: uppercase;
}

.nav-link {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 10px 20px;
  color: var(--text-secondary);
  text-decoration: none;
  font-size: 0.875rem;
  font-weight: 500;
  border-left: 3px solid transparent;
  transition: all var(--transition);
  position: relative;
}

.nav-link:hover {
  color: var(--text-primary);
  background: rgba(123,104,238,0.08);
  border-left-color: var(--accent-purple);
}

.nav-link.active {
  color: var(--accent-violet);
  background: rgba(123,104,238,0.12);
  border-left-color: var(--accent-violet);
  font-weight: 600;
}

.nav-icon { font-size: 1rem; width: 20px; text-align: center; }

.sidebar-footer {
  margin-top: auto;
  padding: 16px 20px;
  border-top: 1px solid var(--border);
  flex-shrink: 0;
}

.theme-toggle {
  display: flex;
  align-items: center;
  gap: 8px;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 8px 14px;
  color: var(--text-secondary);
  font-size: 0.8rem;
  font-weight: 500;
  cursor: pointer;
  width: 100%;
  transition: all var(--transition);
  font-family: 'Plus Jakarta Sans', sans-serif;
}

.theme-toggle:hover { border-color: var(--accent-purple); color: var(--text-primary); }

/* ══════════════════════════════════════════════════════════════════
   TOPBAR
══════════════════════════════════════════════════════════════════ */
.topbar {
  position: fixed;
  top: 0;
  left: var(--sidebar-width);
  right: 0;
  height: var(--topbar-height);
  background: var(--bg-secondary);
  border-bottom: 1px solid var(--border);
  display: flex;
  align-items: center;
  gap: 16px;
  padding: 0 24px;
  z-index: 900;
  backdrop-filter: blur(12px);
}

.hamburger {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 4px;
}

.hamburger span {
  display: block;
  width: 22px;
  height: 2px;
  background: var(--text-secondary);
  border-radius: 2px;
  transition: all var(--transition);
}

.topbar-search {
  flex: 1;
  max-width: 480px;
  position: relative;
}

.search-icon {
  position: absolute;
  left: 12px;
  top: 50%;
  transform: translateY(-50%);
  font-size: 0.9rem;
  pointer-events: none;
}

.topbar-search input {
  width: 100%;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 9px 16px 9px 38px;
  color: var(--text-primary);
  font-size: 0.875rem;
  font-family: 'Plus Jakarta Sans', sans-serif;
  outline: none;
  transition: all var(--transition);
}

.topbar-search input:focus {
  border-color: var(--accent-purple);
  box-shadow: 0 0 0 3px rgba(123,104,238,0.15);
}

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

.search-results {
  position: absolute;
  top: calc(100% + 8px);
  left: 0; right: 0;
  background: var(--bg-card);
  border: 1px solid var(--border-strong);
  border-radius: var(--radius);
  box-shadow: var(--shadow-lg);
  max-height: 320px;
  overflow-y: auto;
  display: none;
  z-index: 1100;
}

.search-results.visible { display: block; }

.search-result-item {
  padding: 10px 16px;
  cursor: pointer;
  border-bottom: 1px solid var(--border);
  transition: background var(--transition);
}

.search-result-item:hover { background: var(--bg-card-hover); }
.search-result-item:last-child { border-bottom: none; }

.search-result-title { font-size: 0.875rem; font-weight: 600; color: var(--text-primary); }
.search-result-sub { font-size: 0.75rem; color: var(--text-muted); margin-top: 2px; }

.topbar-right {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-left: auto;
}

.exam-badge {
  background: linear-gradient(135deg, rgba(123,104,238,0.2), rgba(224,64,251,0.2));
  border: 1px solid var(--border-strong);
  border-radius: 20px;
  padding: 5px 14px;
  font-size: 0.75rem;
  font-weight: 600;
  color: var(--text-accent);
  white-space: nowrap;
}

.theme-toggle-top {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 7px 10px;
  cursor: pointer;
  font-size: 1rem;
  transition: all var(--transition);
}

.theme-toggle-top:hover { border-color: var(--accent-purple); }

/* ══════════════════════════════════════════════════════════════════
   OVERLAY
══════════════════════════════════════════════════════════════════ */
.overlay {
  display: none;
  position: fixed;
  inset: 0;
  background: rgba(0,0,0,0.6);
  z-index: 999;
  backdrop-filter: blur(4px);
}

.overlay.visible { display: block; }

/* ══════════════════════════════════════════════════════════════════
   MAIN CONTENT
══════════════════════════════════════════════════════════════════ */
.main-content {
  margin-left: var(--sidebar-width);
  margin-top: var(--topbar-height);
  padding: 32px;
  min-height: calc(100vh - var(--topbar-height));
}

.section { display: none; animation: fadeSlideIn 0.4s ease; }
.section.active { display: block; }

@keyframes fadeSlideIn {
  from { opacity: 0; transform: translateY(16px); }
  to { opacity: 1; transform: translateY(0); }
}

/* ══════════════════════════════════════════════════════════════════
   SECTION HEADERS
══════════════════════════════════════════════════════════════════ */
.section-header {
  margin-bottom: 28px;
}

.section-title {
  font-family: 'Syne', sans-serif;
  font-size: 1.75rem;
  font-weight: 800;
  color: var(--text-primary);
  letter-spacing: -0.03em;
  margin-bottom: 6px;
}

.section-desc {
  color: var(--text-secondary);
  font-size: 0.9rem;
}

/* ══════════════════════════════════════════════════════════════════
   HERO SECTION
══════════════════════════════════════════════════════════════════ */
.hero-banner {
  background: linear-gradient(135deg, #1B0A3C 0%, #13102A 40%, #0D1B3E 100%);
  border: 1px solid var(--border-strong);
  border-radius: var(--radius-xl);
  padding: 40px;
  display: flex;
  align-items: center;
  gap: 40px;
  position: relative;
  overflow: hidden;
  margin-bottom: 28px;
  box-shadow: var(--shadow-glow);
}

.hero-glow {
  position: absolute;
  top: -60px; right: -60px;
  width: 300px; height: 300px;
  background: radial-gradient(circle, rgba(123,104,238,0.25) 0%, transparent 70%);
  pointer-events: none;
}

.hero-content { flex: 1; }

.hero-badge {
  display: inline-block;
  background: rgba(123,104,238,0.2);
  border: 1px solid rgba(123,104,238,0.4);
  border-radius: 20px;
  padding: 5px 14px;
  font-size: 0.75rem;
  font-weight: 600;
  color: var(--accent-violet);
  letter-spacing: 0.05em;
  margin-bottom: 16px;
}

.hero-title {
  font-family: 'Syne', sans-serif;
  font-size: 2.4rem;
  font-weight: 800;
  line-height: 1.15;
  letter-spacing: -0.04em;
  color: var(--text-primary);
  margin-bottom: 14px;
}

.hero-accent {
  background: linear-gradient(135deg, var(--accent-violet), var(--accent-pink));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-desc {
  color: var(--text-secondary);
  font-size: 0.9rem;
  max-width: 480px;
  margin-bottom: 24px;
  line-height: 1.7;
}

.hero-stats {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
}

.stat-pill {
  background: rgba(255,255,255,0.06);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 8px 16px;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 2px;
}

.stat-num {
  font-family: 'Syne', sans-serif;
  font-size: 1.2rem;
  font-weight: 800;
  color: var(--accent-violet);
}

.stat-lbl {
  font-size: 0.65rem;
  color: var(--text-muted);
  font-weight: 600;
  letter-spacing: 0.05em;
  text-transform: uppercase;
}

.hero-visual {
  flex-shrink: 0;
  width: 280px;
  height: 280px;
  display: flex;
  align-items: center;
  justify-content: center;
}

/* ── QUICK STATS ── */
.quick-stats-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 16px;
  margin-bottom: 20px;
}

.qstat-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 20px;
  display: flex;
  align-items: flex-start;
  gap: 14px;
  transition: all var(--transition);
  cursor: default;
}

.qstat-card:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-md);
  border-color: var(--border-strong);
}

.qstat-card.hot { border-left: 3px solid var(--critical-color); }
.qstat-card.high { border-left: 3px solid var(--accent-purple); }
.qstat-card.medium { border-left: 3px solid var(--high-color); }
.qstat-card.safe { border-left: 3px solid var(--medium-color); }

.qstat-icon { font-size: 1.8rem; flex-shrink: 0; }
.qstat-title { font-size: 0.7rem; color: var(--text-muted); font-weight: 600; text-transform: uppercase; letter-spacing: 0.06em; margin-bottom: 4px; }
.qstat-value { font-family: 'Syne', sans-serif; font-size: 0.95rem; font-weight: 700; color: var(--text-primary); margin-bottom: 3px; }
.qstat-sub { font-size: 0.72rem; color: var(--text-secondary); }

/* ── ALERT BANNER ── */
.alert-banner {
  background: linear-gradient(135deg, rgba(255,71,87,0.1), rgba(255,71,87,0.05));
  border: 1px solid rgba(255,71,87,0.3);
  border-radius: var(--radius);
  padding: 14px 20px;
  font-size: 0.85rem;
  color: var(--text-primary);
  display: flex;
  align-items: flex-start;
  gap: 10px;
  line-height: 1.6;
}

.alert-icon { font-size: 1.1rem; flex-shrink: 0; margin-top: 1px; }

/* ══════════════════════════════════════════════════════════════════
   SYLLABUS SECTION
══════════════════════════════════════════════════════════════════ */
.unit-filter-bar {
  display: flex;
  gap: 8px;
  margin-bottom: 24px;
  flex-wrap: wrap;
}

.unit-filter-btn {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 7px 18px;
  color: var(--text-secondary);
  font-size: 0.8rem;
  font-weight: 600;
  cursor: pointer;
  transition: all var(--transition);
  font-family: 'Plus Jakarta Sans', sans-serif;
}

.unit-filter-btn:hover { border-color: var(--accent-purple); color: var(--text-primary); }
.unit-filter-btn.active { background: var(--accent-purple); border-color: var(--accent-purple); color: white; }

.units-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 20px;
  margin-bottom: 20px;
}

.unit-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  overflow: hidden;
  transition: all var(--transition);
}

.unit-card:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}

.unit-card-header {
  padding: 18px 20px;
  display: flex;
  align-items: center;
  gap: 12px;
  flex-wrap: wrap;
}

.u1 { background: linear-gradient(135deg, rgba(123,104,238,0.25), rgba(123,104,238,0.1)); border-bottom: 1px solid rgba(123,104,238,0.3); }
.u2 { background: linear-gradient(135deg, rgba(224,64,251,0.25), rgba(224,64,251,0.1)); border-bottom: 1px solid rgba(224,64,251,0.3); }
.u3 { background: linear-gradient(135deg, rgba(0,188,212,0.25), rgba(0,188,212,0.1)); border-bottom: 1px solid rgba(0,188,212,0.3); }
.u4 { background: linear-gradient(135deg, rgba(255,107,43,0.25), rgba(255,107,43,0.1)); border-bottom: 1px solid rgba(255,107,43,0.3); }

.unit-number {
  font-family: 'JetBrains Mono', monospace;
  font-size: 0.7rem;
  font-weight: 500;
  color: var(--text-muted);
  letter-spacing: 0.1em;
}

.unit-name {
  font-family: 'Syne', sans-serif;
  font-size: 1rem;
  font-weight: 700;
  color: var(--text-primary);
  flex: 1;
}

.unit-weight-badge {
  background: rgba(255,255,255,0.1);
  border-radius: 6px;
  padding: 3px 10px;
  font-size: 0.7rem;
  font-weight: 600;
  color: var(--text-secondary);
}

.unit-card-body { padding: 16px 20px; }

.topic-list { display: flex; flex-direction: column; gap: 6px; }

.topic-item {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 7px 10px;
  border-radius: 8px;
  transition: background var(--transition);
  cursor: default;
}

.topic-item:hover { background: rgba(255,255,255,0.04); }

.topic-dot {
  width: 8px; height: 8px;
  border-radius: 50%;
  flex-shrink: 0;
}

.topic-item.critical .topic-dot { background: var(--critical-color); box-shadow: 0 0 6px var(--critical-color); }
.topic-item.high .topic-dot { background: var(--high-color); box-shadow: 0 0 6px var(--high-color); }
.topic-item.medium .topic-dot { background: var(--medium-color); }
.topic-item.low .topic-dot { background: var(--low-color); }

.topic-name {
  flex: 1;
  font-size: 0.82rem;
  color: var(--text-secondary);
  font-weight: 500;
}

.topic-item.critical .topic-name { color: var(--text-primary); font-weight: 600; }
.topic-item.high .topic-name { color: var(--text-primary); }

.topic-tag { font-size: 0.7rem; flex-shrink: 0; }

.legend-row {
  display: flex;
  gap: 20px;
  flex-wrap: wrap;
  padding: 12px 0;
}

.legend-item {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 0.8rem;
  color: var(--text-secondary);
}

.legend-dot {
  width: 10px; height: 10px;
  border-radius: 50%;
}

.legend-dot.critical { background: var(--critical-color); }
.legend-dot.high { background: var(--high-color); }
.legend-dot.medium { background: var(--medium-color); }
.legend-dot.low { background: var(--low-color); }

/* ══════════════════════════════════════════════════════════════════
   PYQ ANALYSIS
══════════════════════════════════════════════════════════════════ */
.papers-timeline {
  display: flex;
  gap: 12px;
  margin-bottom: 28px;
  flex-wrap: wrap;
}

.paper-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 14px 18px;
  text-align: center;
  flex: 1;
  min-width: 110px;
  transition: all var(--transition);
}

.paper-card:hover { transform: translateY(-2px); box-shadow: var(--shadow-sm); }

.paper-card.et { border-top: 3px solid var(--accent-purple); }
.paper-card.mt { border-top: 3px solid var(--accent-cyan); }
.paper-card.mt2 { border-top: 3px solid var(--accent-orange); }

.paper-type { font-size: 0.6rem; font-weight: 700; letter-spacing: 0.1em; color: var(--text-muted); text-transform: uppercase; margin-bottom: 4px; }
.paper-year { font-family: 'Syne', sans-serif; font-size: 0.85rem; font-weight: 700; color: var(--text-primary); margin-bottom: 4px; }
.paper-marks { font-size: 0.72rem; color: var(--text-secondary); }

.charts-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 20px;
  margin-bottom: 28px;
}

.chart-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 20px;
}

.chart-card.wide {
  grid-column: 1 / -1;
}

.chart-title {
  font-family: 'Syne', sans-serif;
  font-size: 0.9rem;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 16px;
}

/* ── FREQUENCY TABLE ── */
.freq-table-wrapper {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  overflow: hidden;
}

.freq-table-header {
  padding: 16px 20px;
  border-bottom: 1px solid var(--border);
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 12px;
}

.freq-table-header h3 {
  font-family: 'Syne', sans-serif;
  font-size: 0.95rem;
  font-weight: 700;
  color: var(--text-primary);
}

.table-filters { display: flex; gap: 6px; flex-wrap: wrap; }

.tbl-filter {
  background: var(--bg-secondary);
  border: 1px solid var(--border);
  border-radius: 6px;
  padding: 4px 12px;
  font-size: 0.75rem;
  font-weight: 600;
  color: var(--text-secondary);
  cursor: pointer;
  transition: all var(--transition);
  font-family: 'Plus Jakarta Sans', sans-serif;
}

.tbl-filter:hover { border-color: var(--accent-purple); color: var(--text-primary); }
.tbl-filter.active { background: var(--accent-purple); border-color: var(--accent-purple); color: white; }

.freq-table-scroll { overflow-x: auto; }

.freq-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.85rem;
}

.freq-table thead tr {
  background: var(--bg-secondary);
}

.freq-table th {
  padding: 12px 16px;
  text-align: left;
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--text-muted);
  white-space: nowrap;
}

.freq-table td {
  padding: 11px 16px;
  border-bottom: 1px solid var(--border);
  color: var(--text-secondary);
  vertical-align: middle;
}

.freq-table tbody tr:hover { background: var(--bg-card-hover); }
.freq-table tbody tr:last-child td { border-bottom: none; }

.freq-bar-wrap {
  width: 100px;
  height: 6px;
  background: var(--bg-secondary);
  border-radius: 3px;
  overflow: hidden;
}

.freq-bar {
  height: 100%;
  border-radius: 3px;
  background: linear-gradient(90deg, var(--accent-purple), var(--accent-pink));
  transition: width 1s ease;
}

.priority-badge {
  display: inline-block;
  padding: 3px 10px;
  border-radius: 20px;
  font-size: 0.7rem;
  font-weight: 700;
}

.priority-badge.critical { background: rgba(255,71,87,0.15); color: var(--critical-color); }
.priority-badge.high { background: rgba(255,165,2,0.15); color: var(--high-color); }
.priority-badge.medium { background: rgba(46,213,115,0.15); color: var(--medium-color); }
.priority-badge.low { background: rgba(116,125,140,0.15); color: var(--low-color); }

.unit-tag {
  display: inline-block;
  padding: 2px 8px;
  border-radius: 4px;
  font-size: 0.68rem;
  font-weight: 700;
  font-family: 'JetBrains Mono', monospace;
}

.unit-tag.u1 { background: rgba(123,104,238,0.15); color: var(--u1-color); }
.unit-tag.u2 { background: rgba(224,64,251,0.15); color: var(--u2-color); }
.unit-tag.u3 { background: rgba(0,188,212,0.15); color: var(--u3-color); }
.unit-tag.u4 { background: rgba(255,107,43,0.15); color: var(--u4-color); }

/* ══════════════════════════════════════════════════════════════════
   WEIGHTAGE SECTION
══════════════════════════════════════════════════════════════════ */
.weightage-cards {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 20px;
  margin-bottom: 24px;
}

.wt-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 24px;
  position: relative;
  overflow: hidden;
  transition: all var(--transition);
}

.wt-card:hover { transform: translateY(-3px); box-shadow: var(--shadow-md); }

.u1-bg::before { content: ''; position: absolute; top: 0; left: 0; right: 0; height: 3px; background: var(--u1-color); }
.u2-bg::before { content: ''; position: absolute; top: 0; left: 0; right: 0; height: 3px; background: var(--u2-color); }
.u3-bg::before { content: ''; position: absolute; top: 0; left: 0; right: 0; height: 3px; background: var(--u3-color); }
.u4-bg::before { content: ''; position: absolute; top: 0; left: 0; right: 0; height: 3px; background: var(--u4-color); }

.wt-rank {
  font-family: 'JetBrains Mono', monospace;
  font-size: 0.7rem;
  color: var(--text-muted);
  margin-bottom: 6px;
}

.wt-unit {
  font-family: 'JetBrains Mono', monospace;
  font-size: 0.75rem;
  color: var(--text-muted);
  letter-spacing: 0.08em;
  margin-bottom: 4px;
}

.wt-name {
  font-family: 'Syne', sans-serif;
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 12px;
}

.wt-percent {
  font-family: 'Syne', sans-serif;
  font-size: 2.2rem;
  font-weight: 800;
  color: var(--text-accent);
  margin-bottom: 10px;
}

.wt-bar-wrap {
  width: 100%;
  height: 8px;
  background: var(--bg-secondary);
  border-radius: 4px;
  overflow: hidden;
  margin-bottom: 12px;
}

.wt-bar {
  height: 100%;
  border-radius: 4px;
  background: linear-gradient(90deg, var(--accent-purple), var(--accent-pink));
  transition: width 1.5s cubic-bezier(0.4, 0, 0.2, 1);
}

.u1-bg .wt-bar { background: linear-gradient(90deg, #7B68EE, #9B8FFF); }
.u2-bg .wt-bar { background: linear-gradient(90deg, #E040FB, #FF80FF); }
.u3-bg .wt-bar { background: linear-gradient(90deg, #00BCD4, #00E5FF); }
.u4-bg .wt-bar { background: linear-gradient(90deg, #FF6B2B, #FFB088); }

.wt-details {
  display: flex;
  gap: 16px;
  margin-bottom: 10px;
}

.wt-details span {
  font-size: 0.75rem;
  color: var(--text-secondary);
}

.wt-topics {
  font-size: 0.75rem;
  color: var(--text-muted);
  line-height: 1.5;
}

/* ══════════════════════════════════════════════════════════════════
   IMPORTANT TOPICS PROBABILITY
══════════════════════════════════════════════════════════════════ */
.prob-legend {
  display: flex;
  gap: 10px;
  margin-bottom: 24px;
  flex-wrap: wrap;
}

.prob-badge {
  padding: 5px 14px;
  border-radius: 20px;
  font-size: 0.75rem;
  font-weight: 700;
}

.p-very-high { background: rgba(255,71,87,0.15); color: var(--critical-color); border: 1px solid rgba(255,71,87,0.3); }
.p-high { background: rgba(255,165,2,0.15); color: var(--high-color); border: 1px solid rgba(255,165,2,0.3); }
.p-medium { background: rgba(46,213,115,0.15); color: var(--medium-color); border: 1px solid rgba(46,213,115,0.3); }
.p-low { background: rgba(116,125,140,0.15); color: var(--low-color); border: 1px solid rgba(116,125,140,0.3); }

.topics-prob-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 14px;
}

.topic-prob-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 16px;
  transition: all var(--transition);
}

.topic-prob-card:hover { transform: translateY(-2px); box-shadow: var(--shadow-sm); border-color: var(--border-strong); }

.tpc-header {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 8px;
  margin-bottom: 10px;
}

.tpc-name {
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--text-primary);
  line-height: 1.4;
}

.tpc-prob {
  font-family: 'Syne', sans-serif;
  font-size: 1.1rem;
  font-weight: 800;
  flex-shrink: 0;
}

.tpc-prob.very-high { color: var(--critical-color); }
.tpc-prob.high { color: var(--high-color); }
.tpc-prob.medium { color: var(--medium-color); }
.tpc-prob.low { color: var(--low-color); }

.tpc-bar-wrap {
  width: 100%;
  height: 4px;
  background: var(--bg-secondary);
  border-radius: 2px;
  overflow: hidden;
  margin-bottom: 8px;
}

.tpc-bar {
  height: 100%;
  border-radius: 2px;
  transition: width 1.2s ease;
}

.tpc-bar.very-high { background: var(--critical-color); }
.tpc-bar.high { background: var(--high-color); }
.tpc-bar.medium { background: var(--medium-color); }
.tpc-bar.low { background: var(--low-color); }

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

.tpc-unit { font-size: 0.68rem; color: var(--text-muted); }
.tpc-times { font-size: 0.68rem; color: var(--text-muted); }

/* ══════════════════════════════════════════════════════════════════
   PREDICTED QUESTIONS
══════════════════════════════════════════════════════════════════ */
.predicted-paper {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  overflow: hidden;
}

.paper-header-box {
  background: linear-gradient(135deg, rgba(123,104,238,0.15), rgba(224,64,251,0.1));
  border-bottom: 1px solid var(--border);
  padding: 20px 24px;
  text-align: center;
}

.paper-meta {
  font-size: 0.85rem;
  color: var(--text-secondary);
  margin-bottom: 4px;
}

.paper-note {
  font-size: 0.8rem;
  color: var(--text-muted);
  margin-top: 8px;
  font-style: italic;
}

.pred-unit-label {
  padding: 10px 24px;
  font-family: 'Syne', sans-serif;
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
}

.u1-label { background: rgba(123,104,238,0.1); color: var(--u1-color); border-top: 1px solid rgba(123,104,238,0.2); }
.u2-label { background: rgba(224,64,251,0.1); color: var(--u2-color); border-top: 1px solid rgba(224,64,251,0.2); }
.u3-label { background: rgba(0,188,212,0.1); color: var(--u3-color); border-top: 1px solid rgba(0,188,212,0.2); }
.u4-label { background: rgba(255,107,43,0.1); color: var(--u4-color); border-top: 1px solid rgba(255,107,43,0.2); }

.pred-question-block {
  padding: 20px 24px;
  border-bottom: 1px solid var(--border);
}

.pred-question-block:last-child { border-bottom: none; }

.pred-q-header {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 14px;
  flex-wrap: wrap;
}

.pred-q-num {
  font-family: 'Syne', sans-serif;
  font-size: 1rem;
  font-weight: 800;
  color: var(--text-primary);
}

.pred-q-type {
  font-size: 0.78rem;
  color: var(--text-secondary);
  flex: 1;
}

.confidence-badge {
  padding: 3px 10px;
  border-radius: 20px;
  font-size: 0.7rem;
  font-weight: 700;
}

.c-very-high { background: rgba(255,71,87,0.15); color: var(--critical-color); }
.c-high { background: rgba(255,165,2,0.15); color: var(--high-color); }
.c-medium { background: rgba(46,213,115,0.15); color: var(--medium-color); }

.pred-q-list { display: flex; flex-direction: column; gap: 8px; }

.pred-q-item {
  display: flex;
  align-items: flex-start;
  gap: 10px;
  padding: 10px 14px;
  background: var(--bg-secondary);
  border-radius: 8px;
  font-size: 0.85rem;
  color: var(--text-secondary);
  line-height: 1.5;
}

.pred-q-label {
  font-weight: 700;
  color: var(--accent-violet);
  flex-shrink: 0;
  font-family: 'JetBrains Mono', monospace;
}

.marks-badge {
  margin-left: auto;
  flex-shrink: 0;
  background: rgba(123,104,238,0.15);
  color: var(--accent-violet);
  padding: 2px 8px;
  border-radius: 4px;
  font-size: 0.7rem;
  font-weight: 700;
  font-family: 'JetBrains Mono', monospace;
}

/* ══════════════════════════════════════════════════════════════════
   FORMULA SHEET
══════════════════════════════════════════════════════════════════ */
.formula-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 20px;
}

.formula-unit-block {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  overflow: hidden;
}

.formula-unit-header {
  padding: 14px 18px;
  font-family: 'Syne', sans-serif;
  font-size: 0.85rem;
  font-weight: 700;
  display: flex;
  align-items: center;
  gap: 8px;
}

.formula-unit-header.u1h { background: rgba(123,104,238,0.15); color: var(--u1-color); border-bottom: 1px solid rgba(123,104,238,0.2); }
.formula-unit-header.u2h { background: rgba(224,64,251,0.15); color: var(--u2-color); border-bottom: 1px solid rgba(224,64,251,0.2); }
.formula-unit-header.u3h { background: rgba(0,188,212,0.15); color: var(--u3-color); border-bottom: 1px solid rgba(0,188,212,0.2); }
.formula-unit-header.u4h { background: rgba(255,107,43,0.15); color: var(--u4-color); border-bottom: 1px solid rgba(255,107,43,0.2); }

.formula-list { padding: 12px; display: flex; flex-direction: column; gap: 6px; }

.formula-item {
  display: flex;
  align-items: flex-start;
  gap: 12px;
  padding: 10px 12px;
  background: var(--bg-secondary);
  border-radius: 8px;
  transition: background var(--transition);
}

.formula-item:hover { background: var(--bg-card-hover); }

.formula-expr {
  font-family: 'JetBrains Mono', monospace;
  font-size: 0.82rem;
  color: var(--accent-cyan);
  flex-shrink: 0;
  min-width: 160px;
  font-weight: 500;
}

.formula-desc {
  font-size: 0.78rem;
  color: var(--text-secondary);
  line-height: 1.4;
}

/* ══════════════════════════════════════════════════════════════════
   DEFINITIONS
══════════════════════════════════════════════════════════════════ */
.definitions-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 16px;
}

.def-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 18px;
  transition: all var(--transition);
}

.def-card:hover { border-color: var(--border-strong); transform: translateY(-1px); }

.def-term {
  font-family: 'Syne', sans-serif;
  font-size: 0.9rem;
  font-weight: 700;
  color: var(--accent-violet);
  margin-bottom: 8px;
  display: flex;
  align-items: center;
  gap: 8px;
}

.def-unit-tag {
  font-size: 0.62rem;
  font-family: 'JetBrains Mono', monospace;
  padding: 2px 6px;
  border-radius: 4px;
  font-weight: 500;
}

.def-text {
  font-size: 0.82rem;
  color: var(--text-secondary);
  line-height: 1.6;
}

/* ══════════════════════════════════════════════════════════════════
   DERIVATIONS
══════════════════════════════════════════════════════════════════ */
.derivations-list { display: flex; flex-direction: column; gap: 16px; }

.deriv-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  overflow: hidden;
  transition: all var(--transition);
}

.deriv-header {
  padding: 16px 20px;
  display: flex;
  align-items: center;
  gap: 14px;
  cursor: pointer;
  user-select: none;
}

.deriv-header:hover { background: var(--bg-card-hover); }

.deriv-rank {
  width: 32px; height: 32px;
  border-radius: 8px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: 'Syne', sans-serif;
  font-size: 0.85rem;
  font-weight: 800;
  flex-shrink: 0;
}

.deriv-rank.r1 { background: rgba(255,71,87,0.2); color: var(--critical-color); }
.deriv-rank.r2 { background: rgba(255,165,2,0.2); color: var(--high-color); }
.deriv-rank.r3 { background: rgba(123,104,238,0.2); color: var(--accent-purple); }

.deriv-title {
  flex: 1;
  font-family: 'Syne', sans-serif;
  font-size: 0.95rem;
  font-weight: 700;
  color: var(--text-primary);
}

.deriv-meta {
  display: flex;
  align-items: center;
  gap: 8px;
}

.deriv-freq {
  font-size: 0.72rem;
  color: var(--text-muted);
}

.deriv-toggle {
  color: var(--text-muted);
  font-size: 0.8rem;
  transition: transform var(--transition);
}

.deriv-card.open .deriv-toggle { transform: rotate(180deg); }

.deriv-body {
  display: none;
  padding: 0 20px 20px;
  border-top: 1px solid var(--border);
}

.deriv-card.open .deriv-body { display: block; }

.deriv-steps { display: flex; flex-direction: column; gap: 8px; margin-top: 14px; }

.deriv-step {
  display: flex;
  gap: 12px;
  align-items: flex-start;
}

.step-num {
  width: 24px; height: 24px;
  border-radius: 50%;
  background: rgba(123,104,238,0.2);
  color: var(--accent-violet);
  font-size: 0.7rem;
  font-weight: 700;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  margin-top: 1px;
}

.step-text {
  font-size: 0.82rem;
  color: var(--text-secondary);
  line-height: 1.5;
}

.step-formula {
  font-family: 'JetBrains Mono', monospace;
  font-size: 0.8rem;
  color: var(--accent-cyan);
  background: var(--bg-secondary);
  padding: 6px 12px;
  border-radius: 6px;
  margin-top: 4px;
  display: block;
}

/* ══════════════════════════════════════════════════════════════════
   NUMERICALS
══════════════════════════════════════════════════════════════════ */
.numericals-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 16px;
}

.num-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 20px;
  transition: all var(--transition);
}

.num-card:hover { border-color: var(--border-strong); transform: translateY(-2px); box-shadow: var(--shadow-sm); }

.num-header {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 10px;
  margin-bottom: 12px;
}

.num-title {
  font-family: 'Syne', sans-serif;
  font-size: 0.9rem;
  font-weight: 700;
  color: var(--text-primary);
  line-height: 1.3;
}

.num-freq-badge {
  background: rgba(123,104,238,0.15);
  color: var(--accent-violet);
  padding: 3px 8px;
  border-radius: 6px;
  font-size: 0.68rem;
  font-weight: 700;
  white-space: nowrap;
  flex-shrink: 0;
}

.num-question {
  font-size: 0.82rem;
  color: var(--text-secondary);
  line-height: 1.6;
  margin-bottom: 12px;
  padding: 10px 12px;
  background: var(--bg-secondary);
  border-radius: 8px;
  border-left: 3px solid var(--accent-purple);
}

.num-approach {
  font-size: 0.78rem;
  color: var(--text-muted);
  line-height: 1.5;
}

.num-approach strong { color: var(--accent-cyan); }

/* ══════════════════════════════════════════════════════════════════
   STRATEGY SECTION
══════════════════════════════════════════════════════════════════ */
.strategy-timeline { display: flex; flex-direction: column; gap: 16px; margin-bottom: 28px; }

.strat-phase {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  overflow: hidden;
}

.strat-phase-header {
  padding: 14px 20px;
  display: flex;
  align-items: center;
  gap: 12px;
  font-family: 'Syne', sans-serif;
  font-size: 0.9rem;
  font-weight: 700;
}

.phase-1 { background: rgba(123,104,238,0.15); color: var(--u1-color); }
.phase-2 { background: rgba(224,64,251,0.15); color: var(--u2-color); }
.phase-3 { background: rgba(0,188,212,0.15); color: var(--u3-color); }
.phase-4 { background: rgba(255,107,43,0.15); color: var(--u4-color); }
.phase-5 { background: rgba(105,255,71,0.15); color: var(--medium-color); }

.phase-icon { font-size: 1.1rem; }
.phase-title { flex: 1; }

.strat-phase-body { padding: 14px 20px; display: flex; flex-direction: column; gap: 8px; }

.strat-item {
  display: flex;
  align-items: flex-start;
  gap: 10px;
  font-size: 0.85rem;
  color: var(--text-secondary);
  line-height: 1.5;
}

.strat-check {
  color: var(--medium-color);
  font-weight: 700;
  flex-shrink: 0;
  margin-top: 1px;
}

.strategy-tips-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 16px;
}

.stip-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 20px;
}

.stip-icon { font-size: 1.5rem; margin-bottom: 10px; }

.stip-title {
  font-family: 'Syne', sans-serif;
  font-size: 0.9rem;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 12px;
}

.stip-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.stip-list li {
  font-size: 0.82rem;
  color: var(--text-secondary);
  padding-left: 14px;
  position: relative;
  line-height: 1.5;
}

.stip-list li::before {
  content: '→';
  position: absolute;
  left: 0;
  color: var(--accent-purple);
  font-size: 0.75rem;
}

/* ══════════════════════════════════════════════════════════════════
   EXAM TIPS
══════════════════════════════════════════════════════════════════ */
.tips-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
}

.tip-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 20px;
  transition: all var(--transition);
}

.tip-card:hover { transform: translateY(-2px); box-shadow: var(--shadow-sm); border-color: var(--border-strong); }

.tip-icon { font-size: 1.8rem; margin-bottom: 10px; }

.tip-title {
  font-family: 'Syne', sans-serif;
  font-size: 0.9rem;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 8px;
}

.tip-text {
  font-size: 0.82rem;
  color: var(--text-secondary);
  line-height: 1.6;
}

/* ══════════════════════════════════════════════════════════════════
   SURVIVAL GUIDE
══════════════════════════════════════════════════════════════════ */
.survival-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
  margin-bottom: 28px;
}

.survival-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 24px;
  transition: all var(--transition);
}

.survival-card:hover { transform: translateY(-3px); box-shadow: var(--shadow-md); }

.day-before { border-top: 3px solid var(--accent-purple); }
.exam-morning { border-top: 3px solid var(--accent-yellow); }
.exam-hall { border-top: 3px solid var(--accent-green); }

.survival-icon { font-size: 2rem; margin-bottom: 12px; }

.survival-title {
  font-family: 'Syne', sans-serif;
  font-size: 1rem;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 16px;
}

.survival-content { display: flex; flex-direction: column; gap: 8px; }

.surv-item {
  font-size: 0.82rem;
  color: var(--text-secondary);
  line-height: 1.5;
  padding: 6px 10px;
  background: var(--bg-secondary);
  border-radius: 6px;
}

/* ── NEVER SKIP BOX ── */
.never-skip-box {
  background: linear-gradient(135deg, rgba(255,71,87,0.08), rgba(255,71,87,0.03));
  border: 1px solid rgba(255,71,87,0.25);
  border-radius: var(--radius-lg);
  padding: 24px;
  margin-bottom: 24px;
}

.never-skip-title {
  font-family: 'Syne', sans-serif;
  font-size: 1rem;
  font-weight: 800;
  color: var(--critical-color);
  margin-bottom: 16px;
  letter-spacing: 0.05em;
}

.never-skip-grid { display: flex; flex-direction: column; gap: 8px; }

.ns-item {
  display: flex;
  align-items: center;
  gap: 14px;
  padding: 10px 14px;
  background: var(--bg-card);
  border-radius: 8px;
  border: 1px solid var(--border);
}

.ns-num {
  width: 26px; height: 26px;
  border-radius: 6px;
  background: rgba(255,71,87,0.15);
  color: var(--critical-color);
  font-size: 0.75rem;
  font-weight: 800;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  font-family: 'Syne', sans-serif;
}

.ns-text {
  flex: 1;
  font-size: 0.85rem;
  color: var(--text-primary);
  font-weight: 500;
}

.ns-marks {
  font-family: 'JetBrains Mono', monospace;
  font-size: 0.72rem;
  color: var(--accent-violet);
  background: rgba(123,104,238,0.1);
  padding: 2px 8px;
  border-radius: 4px;
  flex-shrink: 0;
}

/* ── CONCLUSION BOX ── */
.conclusion-box {
  background: linear-gradient(135deg, rgba(123,104,238,0.1), rgba(224,64,251,0.08));
  border: 1px solid var(--border-strong);
  border-radius: var(--radius-lg);
  padding: 28px;
}

.conclusion-title {
  font-family: 'Syne', sans-serif;
  font-size: 1.1rem;
  font-weight: 800;
  color: var(--text-primary);
  margin-bottom: 14px;
}

.conclusion-box p {
  font-size: 0.88rem;
  color: var(--text-secondary);
  line-height: 1.7;
  margin-bottom: 20px;
}

.conclusion-box p strong { color: var(--accent-violet); }

.conclusion-score { display: flex; flex-direction: column; gap: 8px; }

.score-item {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 10px 16px;
  background: var(--bg-card);
  border-radius: 8px;
  border: 1px solid var(--border);
}

.score-label { font-size: 0.82rem; color: var(--text-secondary); }

.score-val {
  font-family: 'Syne', sans-serif;
  font-size: 0.95rem;
  font-weight: 800;
  color: var(--medium-color);
}

/* ══════════════════════════════════════════════════════════════════
   RESPONSIVE
══════════════════════════════════════════════════════════════════ */
@media (max-width: 1200px) {
  .quick-stats-grid { grid-template-columns: repeat(2, 1fr); }
  .topics-prob-grid { grid-template-columns: repeat(2, 1fr); }
  .tips-grid { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 900px) {
  :root { --sidebar-width: 0px; }

  .sidebar {
    width: 270px;
    transform: translateX(-100%);
  }

  .sidebar.open {
    transform: translateX(0);
    box-shadow: var(--shadow-lg);
  }

  .sidebar-close { display: block; }

  .topbar { left: 0; }
  .hamburger { display: flex; }
  .main-content { margin-left: 0; padding: 20px 16px; }

  .hero-banner { flex-direction: column; padding: 28px 20px; }
  .hero-visual { width: 220px; height: 220px; }
  .hero-title { font-size: 1.8rem; }

  .units-grid { grid-template-columns: 1fr; }
  .charts-grid { grid-template-columns: 1fr; }
  .weightage-cards { grid-template-columns: 1fr; }
  .formula-grid { grid-template-columns: 1fr; }
  .definitions-grid { grid-template-columns: 1fr; }
  .numericals-grid { grid-template-columns: 1fr; }
  .strategy-tips-grid { grid-template-columns: 1fr; }
  .survival-grid { grid-template-columns: 1fr; }
  .topics-prob-grid { grid-template-columns: 1fr; }
  .tips-grid { grid-template-columns: 1fr; }
  .quick-stats-grid { grid-template-columns: 1fr; }
}

@media (max-width: 600px) {
  .hero-stats { gap: 8px; }
  .stat-pill { padding: 6px 12px; }
  .exam-badge { display: none; }
  .papers-timeline { gap: 8px; }
  .paper-card { min-width: 80px; padding: 10px 12px; }
}

/* ══════════════════════════════════════════════════════════════════
   UTILITY ANIMATIONS
══════════════════════════════════════════════════════════════════ */
@keyframes shimmer {
  0% { background-position: -200% 0; }
  100% { background-position: 200% 0; }
}

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

/* Scroll reveal */
.reveal {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 0.5s ease, transform 0.5s ease;
}

.reveal.visible {
  opacity: 1;
  transform: translateY(0);
}