/* =========================================
   JEE Maths Master – n2.css (Updated)
   New: Login, Difficulty, Sound, Charts, Leaderboard, Dark Mode Toggle
   ========================================= */

:root {
  --primary: #4361ee;
  --primary-light: #4895ef;
  --secondary: #f72585;
  --success: #4cc9f0;
  --warning: #f9c74f;
  --danger: #f94144;
  --info: #7209b7;

  --bg-primary: #f8fafc;
  --bg-secondary: #ffffff;
  --bg-gradient: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  --text-primary: #1e293b;
  --text-secondary: #64748b;
  --text-light: #94a3b8;

  --glass-bg: rgba(255,255,255,0.25);
  --glass-border: rgba(255,255,255,0.18);
  --glass-shadow: 0 8px 32px 0 rgba(31,38,135,0.37);
  --glass-blur: blur(16px);

  --card-bg: rgba(255,255,255,0.95);
  --input-bg: #f8fafc;
}

/* ===== DARK MODE ===== */
body.dark {
  --bg-primary: #0f172a;
  --bg-secondary: #1e293b;
  --bg-gradient: linear-gradient(135deg, #050814 0%, #111827 48%, #12343b 100%);
  --text-primary: #f1f5f9;
  --text-secondary: #94a3b8;
  --glass-bg: rgba(30,41,59,0.7);
  --glass-border: rgba(255,255,255,0.1);
  --card-bg: rgba(30,41,59,0.97);
  --input-bg: #1e293b;
}

body.dark .dashboard,
body.dark .card,
body.dark .quiz,
body.dark .result-container,
body.dark .leaderboard {
  background: rgba(30,41,59,0.97);
  color: var(--text-primary);
}

body.dark .question-container,
body.dark .option,
body.dark .review-item,
body.dark .solution,
body.dark .name-input,
body.dark .login-card {
  background: rgba(15,23,42,0.9);
  color: var(--text-primary);
}

body.dark .option {
  border-color: rgba(255,255,255,0.1);
}

body.dark .leaderboard-item {
  background: rgba(255,255,255,0.07);
}

body.dark h3, body.dark h4, body.dark p, body.dark span {
  color: var(--text-primary);
}

body.dark .timer-container {
  background: rgba(15,23,42,0.8);
}

/* Theme is controlled by the toggle through body.dark. */

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

body {
  font-family: 'Segoe UI', 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
  background: var(--bg-gradient);
  color: var(--text-primary);
  line-height: 1.7;
  min-height: 100vh;
  overflow-x: hidden;
}

/* ===== PARTICLES ===== */
.particles {
  position: fixed; top: 0; left: 0;
  width: 100%; height: 100%;
  z-index: -1; pointer-events: none;
}

.particle {
  position: absolute;
  background: rgba(255,255,255,0.1);
  border-radius: 50%;
  animation: float 6s ease-in-out infinite;
}

@keyframes float {
  0%, 100% { transform: translateY(0px) rotate(0deg); }
  50% { transform: translateY(-20px) rotate(180deg); }
}

/* ===== LOGIN SCREEN ===== */
.login-overlay {
  position: fixed; inset: 0;
  background: var(--bg-gradient);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 9999;
  min-height: 100dvh;
  padding: 1rem;
  overflow-y: auto;
  overscroll-behavior: contain;
  -webkit-overflow-scrolling: touch;
}

.login-card {
  background: rgba(255,255,255,0.18);
  backdrop-filter: blur(24px);
  -webkit-backdrop-filter: blur(24px);
  border: 1px solid rgba(255,255,255,0.3);
  border-radius: 28px;
  padding: 3rem 2.5rem;
  width: 100%;
  max-width: 460px;
  margin: auto;
  text-align: center;
  box-shadow: 0 20px 60px rgba(0,0,0,0.25);
  animation: bounceIn 0.6s ease;
}

.login-logo .login-icon {
  width: 80px; height: 80px;
  background: linear-gradient(135deg, var(--primary), var(--primary-light));
  border-radius: 50%;
  display: flex; align-items: center; justify-content: center;
  font-size: 2.5rem; color: white;
  margin: 0 auto 1rem;
  box-shadow: 0 8px 25px rgba(67,97,238,0.5);
}

.login-logo h1 {
  font-size: 2rem; font-weight: 800;
  color: white;
  text-shadow: 0 2px 8px rgba(0,0,0,0.3);
}

.login-logo p {
  color: rgba(255,255,255,0.75);
  margin-top: 0.3rem; margin-bottom: 0.35rem;
  font-size: 1rem;
}

.login-logo .login-tagline {
  margin-bottom: 2rem;
  color: #fff;
  font-weight: 800;
}

.avatar-label {
  color: rgba(255,255,255,0.85);
  font-size: 0.95rem;
  margin-bottom: 0.75rem;
}

.avatar-grid {
  display: grid;
  grid-template-columns: repeat(6, 1fr);
  gap: 0.5rem;
  margin-bottom: 1.5rem;
}

.avatar-option {
  display: grid;
  place-items: center;
  aspect-ratio: 1;
  font-size: 1.8rem;
  line-height: 1;
  padding: 0.4rem;
  border-radius: 12px;
  cursor: pointer;
  transition: all 0.2s ease;
  border: 2px solid transparent;
  background: rgba(255,255,255,0.1);
}

.avatar-option:hover {
  transform: scale(1.2);
  background: rgba(255,255,255,0.2);
}

.avatar-option.selected {
  border-color: var(--warning);
  background: rgba(249,199,79,0.2);
  transform: scale(1.2);
}

.name-input {
  width: 100%;
  padding: 1rem 1.5rem;
  border-radius: 15px;
  border: 2px solid rgba(255,255,255,0.3);
  background: rgba(255,255,255,0.15);
  color: white;
  font-size: 1rem;
  margin-bottom: 1rem;
  outline: none;
  transition: all 0.3s;
  backdrop-filter: blur(8px);
}

.name-input::placeholder { color: rgba(255,255,255,0.6); }

.name-input:focus {
  border-color: var(--warning);
  background: rgba(255,255,255,0.25);
}

.login-form {
  display: flex;
  flex-direction: column;
  gap: 0.85rem;
}

.login-form .name-input,
.login-form .btn {
  margin-bottom: 0;
}

.btn-lg {
  width: 100%;
  padding: 1.2rem;
  font-size: 1.1rem;
  border-radius: 15px;
  justify-content: center;
}

.auth-link-button {
  align-self: center;
  border: 0;
  background: transparent;
  color: rgba(255,255,255,0.86);
  font: inherit;
  font-size: 0.9rem;
  cursor: pointer;
  padding: 0.25rem 0.5rem;
  text-decoration: underline;
  text-underline-offset: 4px;
}

.auth-link-button:hover,
.auth-link-button:focus-visible {
  color: #ffffff;
  outline: none;
}

.referral-status {
  min-height: 1.1rem;
  color: rgba(255,255,255,0.76);
  font-size: 0.86rem;
  font-weight: 700;
  margin: -0.25rem 0 0;
}

.referral-status.success {
  color: #bbf7d0;
}

.referral-status.error {
  color: #fecaca;
}

.auth-note {
  color: rgba(255,255,255,0.82);
  font-size: 0.9rem;
  line-height: 1.5;
  margin-top: 0.25rem;
}

.auth-status {
  min-height: 1.2rem;
  font-size: 0.9rem;
  color: #ffffff;
}

.auth-status.error {
  color: #fee2e2;
}

.auth-status.success {
  color: #d1fae5;
}

/* ===== DIFFICULTY MODAL ===== */
.modal-overlay {
  position: fixed; inset: 0;
  background: rgba(0,0,0,0.6);
  backdrop-filter: blur(6px);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 8000;
  padding: 1rem;
}

.modal-card {
  background: var(--card-bg);
  border-radius: 25px;
  padding: 2.5rem;
  width: 100%;
  max-width: 520px;
  text-align: center;
  box-shadow: 0 25px 60px rgba(0,0,0,0.3);
  animation: bounceIn 0.4s ease;
}

.modal-card h2 {
  font-size: 1.8rem;
  color: var(--primary);
  margin-bottom: 0.5rem;
}

.modal-subtitle {
  color: var(--text-secondary);
  font-size: 0.95rem;
  margin-bottom: 1.5rem;
}

.difficulty-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1rem;
}

.difficulty-card {
  padding: 1.5rem 1rem;
  border-radius: 18px;
  cursor: pointer;
  transition: all 0.3s ease;
  border: 2px solid transparent;
}

.difficulty-card:hover {
  transform: translateY(-5px);
  box-shadow: 0 10px 30px rgba(0,0,0,0.15);
}

.difficulty-card.easy {
  background: linear-gradient(135deg, #d1fae5, #a7f3d0);
  border-color: #10b981;
}
.difficulty-card.easy:hover { border-color: #059669; background: linear-gradient(135deg,#a7f3d0,#6ee7b7); }

.difficulty-card.medium {
  background: linear-gradient(135deg, #fef9c3, #fde68a);
  border-color: #f59e0b;
}
.difficulty-card.medium:hover { border-color: #d97706; background: linear-gradient(135deg,#fde68a,#fcd34d); }

.difficulty-card.hard {
  background: linear-gradient(135deg, #fee2e2, #fca5a5);
  border-color: #ef4444;
}
.difficulty-card.hard:hover { border-color: #dc2626; background: linear-gradient(135deg,#fca5a5,#f87171); }

.difficulty-card.all {
  background: linear-gradient(135deg, #ede9fe, #c4b5fd);
  border-color: #7c3aed;
}
.difficulty-card.all:hover { border-color: #6d28d9; background: linear-gradient(135deg,#c4b5fd,#a78bfa); }

.diff-emoji { font-size: 2.2rem; margin-bottom: 0.5rem; }

.difficulty-card h3 {
  font-size: 1.1rem;
  font-weight: 700;
  color: #1e293b;
  margin-bottom: 0.25rem;
}

.difficulty-card p { font-size: 0.85rem; color: #475569; margin-bottom: 0.4rem; }

.diff-time {
  font-size: 0.8rem;
  font-weight: 600;
  color: #475569;
  background: rgba(255,255,255,0.5);
  padding: 0.25rem 0.6rem;
  border-radius: 20px;
  display: inline-block;
}

.part-modal {
  max-width: 760px;
  text-align: left;
}

.part-modal-header {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: 1rem;
  margin-bottom: 1.25rem;
}

.part-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
  gap: 0.8rem;
  max-height: min(58vh, 520px);
  overflow-y: auto;
  padding-right: 0.25rem;
}

.part-option {
  border: 1px solid rgba(255,255,255,0.16);
  background: rgba(255,255,255,0.08);
  color: var(--text-primary);
  border-radius: 8px;
  padding: 1rem;
  cursor: pointer;
  text-align: left;
  display: flex;
  flex-direction: column;
  gap: 0.25rem;
  transition: all 0.2s ease;
}

.part-option:hover {
  border-color: var(--primary-light);
  background: rgba(67,97,238,0.18);
  transform: translateY(-2px);
}

.part-option.paused {
  border-color: var(--warning);
  background: rgba(249,199,79,0.16);
}

.part-option.attempted,
.part-option:disabled {
  cursor: not-allowed;
  opacity: 0.68;
  transform: none;
}

.part-option.attempted {
  border-color: rgba(34,197,94,0.34);
  background: rgba(34,197,94,0.12);
}

.part-option.attempted .part-action {
  background: rgba(34,197,94,0.85);
}

.part-number {
  font-weight: 800;
  font-size: 1rem;
}

.part-range,
.part-count {
  color: var(--text-secondary);
  font-size: 0.86rem;
}

.part-action {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  width: fit-content;
  margin-top: 0.5rem;
  padding: 0.42rem 0.65rem;
  border-radius: 8px;
  color: #fff;
  background: var(--primary);
  font-size: 0.82rem;
  font-weight: 700;
}

/* ===== HEADER ===== */
.header {
  position: sticky; top: 0;
  padding: 1rem 2rem;
  z-index: 100;
  background: rgba(255,255,255,0.1);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid rgba(255,255,255,0.1);
}

.header-content {
  max-width: 1200px; margin: 0 auto;
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 0.8rem;
}

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

.logo {
  display: flex; align-items: center; gap: 0.8rem;
  font-size: 1.4rem; font-weight: 700;
  color: white;
  text-shadow: 0 2px 4px rgba(0,0,0,0.3);
}

.header-right {
  display: flex; align-items: center; gap: 0.75rem;
  flex-wrap: wrap;
}

.user-profile-pill {
  background: rgba(255,255,255,0.2);
  border: 1px solid rgba(255,255,255,0.3);
  padding: 0.5rem 1rem;
  border-radius: 25px;
  display: flex; align-items: center; gap: 0.5rem;
  color: white; font-weight: 600; cursor: pointer;
  transition: all 0.3s;
  font-size: 0.95rem;
}

.user-profile-pill:hover {
  background: rgba(255,255,255,0.3);
  transform: translateY(-1px);
}

.wallet {
  background: linear-gradient(135deg, var(--primary) 0%, var(--primary-light) 100%);
  padding: 0.6rem 1.2rem;
  border-radius: 25px; font-weight: 600;
  display: flex; align-items: center; gap: 0.5rem;
  color: white;
  box-shadow: 0 4px 15px rgba(67,97,238,0.3);
  transition: all 0.3s;
}

.wallet:hover { transform: translateY(-2px); }

.withdraw-btn {
  border: 1px solid rgba(255,255,255,0.38);
  background: rgba(15,23,42,0.72);
  color: white;
  border-radius: 25px;
  padding: 0.6rem 1rem;
  font-weight: 700;
  display: flex;
  align-items: center;
  gap: 0.5rem;
  cursor: pointer;
  box-shadow: 0 8px 24px rgba(0,0,0,0.18);
  transition: all 0.3s;
}

.withdraw-btn:hover:not(:disabled) {
  background: rgba(255,255,255,0.16);
  transform: translateY(-2px);
}

.withdraw-btn:disabled {
  cursor: not-allowed;
  opacity: 0.62;
}

.withdraw-modal {
  position: fixed;
  inset: 0;
  z-index: 8500;
  background: rgba(2,6,23,0.68);
  backdrop-filter: blur(8px);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 1rem;
}

.withdraw-card {
  width: min(760px, 100%);
  max-height: min(92vh, 820px);
  overflow: auto;
  background: rgba(255,255,255,0.96);
  color: var(--text-primary);
  border: 1px solid rgba(15,23,42,0.12);
  border-radius: 8px;
  box-shadow: 0 24px 70px rgba(0,0,0,0.34);
  padding: 1.5rem;
}

body.dark .withdraw-card {
  background: rgba(15,23,42,0.97);
  border-color: rgba(255,255,255,0.14);
}

.withdraw-header {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 1rem;
  margin-bottom: 1.25rem;
}

.withdraw-header h3 {
  margin: 0.15rem 0 0;
  color: var(--text-primary);
}

.withdraw-kicker {
  color: var(--text-secondary);
  font-size: 0.82rem;
  text-transform: uppercase;
  letter-spacing: 0;
  font-weight: 700;
}

.withdraw-close {
  flex: 0 0 auto;
}

.withdraw-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1rem;
}

.withdraw-grid label {
  display: grid;
  gap: 0.45rem;
  color: var(--text-secondary);
  font-size: 0.9rem;
  font-weight: 700;
}

.withdraw-grid input,
.withdraw-status-select {
  width: 100%;
  min-height: 44px;
  border: 1px solid rgba(148,163,184,0.34);
  background: rgba(255,255,255,0.88);
  color: var(--text-primary);
  border-radius: 8px;
  padding: 0.75rem 0.85rem;
  font: inherit;
}

body.dark .withdraw-grid input,
body.dark .withdraw-status-select {
  background: rgba(2,6,23,0.62);
  border-color: rgba(255,255,255,0.15);
}

.withdraw-grid input[readonly] {
  color: var(--text-secondary);
}

.withdraw-status {
  min-height: 1.4rem;
  margin: 1rem 0 0;
  color: var(--text-secondary);
  font-weight: 700;
}

.withdraw-status.error {
  color: var(--danger);
}

.withdraw-status.success {
  color: var(--success);
}

.withdraw-actions {
  display: flex;
  justify-content: flex-end;
  gap: 0.75rem;
  margin-top: 1.25rem;
}

/* Icon Buttons (Sound, Music, Dark Mode) */
.icon-btn {
  width: 40px; height: 40px;
  border-radius: 50%;
  border: 1px solid rgba(255,255,255,0.3);
  background: rgba(255,255,255,0.15);
  color: white;
  font-size: 1rem;
  cursor: pointer;
  display: flex; align-items: center; justify-content: center;
  transition: all 0.3s;
}

.icon-btn:hover {
  background: rgba(255,255,255,0.3);
  transform: translateY(-2px);
}

.icon-btn.active {
  background: var(--warning);
  border-color: var(--warning);
  color: #1e293b;
}

.sidebar-toggle-btn {
  flex: 0 0 auto;
}

.home-sidebar-backdrop {
  position: fixed;
  inset: 0;
  z-index: 7000;
  background: rgba(2,6,23,0.56);
  backdrop-filter: blur(4px);
}

.home-sidebar {
  position: fixed;
  top: 0;
  left: 0;
  bottom: 0;
  z-index: 7100;
  width: min(380px, 92vw);
  padding: 1.1rem;
  display: flex;
  flex-direction: column;
  gap: 1rem;
  overflow-y: auto;
  color: var(--text-primary);
  background: rgba(15,23,42,0.98);
  border-right: 1px solid rgba(255,255,255,0.12);
  box-shadow: 24px 0 70px rgba(2,6,23,0.42);
  transform: translateX(-105%);
  visibility: hidden;
  pointer-events: none;
  transition: transform 0.24s ease;
}

.home-sidebar.open {
  transform: translateX(0);
  visibility: visible;
  pointer-events: auto;
}

.home-sidebar-header {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: 0.8rem;
  padding: 0.35rem 0 0.75rem;
  border-bottom: 1px solid rgba(148,163,184,0.18);
}

.home-sidebar-user {
  display: flex;
  align-items: center;
  gap: 0.8rem;
  min-width: 0;
}

.home-sidebar-avatar {
  width: 52px;
  height: 52px;
  display: grid;
  place-items: center;
  flex: 0 0 auto;
  border-radius: 14px;
  background: linear-gradient(135deg, #1f72a2, #dd0d45);
  color: #fff;
  font-size: 1.6rem;
  font-weight: 800;
}

.home-sidebar-user h3 {
  margin: 0;
  color: #fff;
  font-size: 1.05rem;
  line-height: 1.25;
}

.home-sidebar-user p {
  margin: 0.15rem 0 0;
  color: rgba(226,232,240,0.72);
  font-size: 0.84rem;
  overflow-wrap: anywhere;
}

.home-sidebar-close {
  width: 36px;
  height: 36px;
}

.home-sidebar-nav {
  display: grid;
  gap: 0.45rem;
}

.home-sidebar-link {
  width: 100%;
  min-height: 44px;
  padding: 0.72rem 0.8rem;
  display: flex;
  align-items: center;
  gap: 0.75rem;
  border: 1px solid transparent;
  border-radius: 8px;
  background: transparent;
  color: rgba(241,245,249,0.82);
  font: inherit;
  font-weight: 700;
  text-align: left;
  cursor: pointer;
  transition: all 0.18s ease;
}

.home-sidebar-link i {
  width: 20px;
  text-align: center;
  color: rgba(125,211,252,0.9);
}

.home-sidebar-link:hover,
.home-sidebar-link.active {
  color: #fff;
  background: rgba(67,97,238,0.24);
  border-color: rgba(125,211,252,0.18);
}

.home-section-tab-backdrop {
  position: fixed;
  inset: 0;
  z-index: 7200;
  background: rgba(2,6,23,0.62);
  backdrop-filter: blur(5px);
}

.home-section-tab {
  position: fixed;
  top: 50%;
  left: 50%;
  z-index: 7300;
  width: min(760px, 92vw);
  max-height: min(86dvh, 780px);
  display: flex;
  flex-direction: column;
  overflow: hidden;
  color: var(--text-primary);
  background: rgba(15,23,42,0.98);
  border: 1px solid rgba(255,255,255,0.12);
  border-radius: 8px;
  box-shadow: 0 26px 80px rgba(2,6,23,0.46);
  opacity: 0;
  visibility: hidden;
  pointer-events: none;
  transform: translate(-50%, calc(-50% + 16px));
  transition: opacity 0.2s ease, transform 0.2s ease;
}

.home-section-tab.open {
  opacity: 1;
  visibility: visible;
  pointer-events: auto;
  transform: translate(-50%, -50%);
}

.home-section-tab-header {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: 1rem;
  padding: 1.15rem 1.25rem;
  border-bottom: 1px solid rgba(148,163,184,0.18);
  flex: 0 0 auto;
}

.home-section-tab-kicker {
  display: block;
  margin-bottom: 0.25rem;
  color: rgba(125,211,252,0.86);
  font-size: 0.75rem;
  font-weight: 800;
  letter-spacing: 0;
  text-transform: uppercase;
}

.home-section-tab-header h3 {
  margin: 0;
  color: #fff;
  font-size: 1.2rem;
}

.home-section-tab-close {
  width: 38px;
  height: 38px;
  flex: 0 0 auto;
}

.home-section-tab-body {
  min-height: 0;
  overflow-y: auto;
  padding: 1.25rem;
}

.home-sidebar-section {
  padding: 1rem;
  border-radius: 8px;
  background: rgba(255,255,255,0.06);
  border: 1px solid rgba(255,255,255,0.1);
}

.home-sidebar-section h4,
.home-section-tab-body h4 {
  margin-bottom: 0.4rem;
  color: #fff;
  font-size: 1rem;
}

.home-sidebar-section h5,
.home-section-tab-body h5 {
  margin: 1rem 0 0.45rem;
  color: #fff;
  font-size: 0.92rem;
}

.home-sidebar-section p,
.home-section-tab-body p {
  color: rgba(226,232,240,0.76);
  font-size: 0.9rem;
  line-height: 1.55;
  margin-bottom: 0.8rem;
}

.home-section-tab-body a {
  color: #93c5fd;
  overflow-wrap: anywhere;
}

.home-section-tab-body a:hover {
  color: #bfdbfe;
}

.sidebar-copy-list {
  display: grid;
  gap: 0.45rem;
  margin: 0 0 0.9rem;
  padding-left: 1.1rem;
  color: rgba(226,232,240,0.76);
  font-size: 0.9rem;
  line-height: 1.5;
}

.sidebar-copy-list li::marker {
  color: var(--primary-light);
}

.sidebar-field {
  display: grid;
  gap: 0.45rem;
  margin: 0.85rem 0;
  color: rgba(226,232,240,0.82);
  font-size: 0.86rem;
  font-weight: 700;
}

.sidebar-field input {
  width: 100%;
  padding: 0.78rem 0.9rem;
  border-radius: 8px;
  border: 1px solid rgba(148,163,184,0.32);
  background: rgba(15,23,42,0.86);
  color: #fff;
  outline: none;
}

.sidebar-field input:focus {
  border-color: var(--primary-light);
  box-shadow: 0 0 0 3px rgba(72,149,239,0.16);
}

.sidebar-avatar-grid {
  display: grid;
  grid-template-columns: repeat(6, minmax(0, 1fr));
  gap: 0.45rem;
}

.sidebar-avatar-option {
  display: grid;
  place-items: center;
  aspect-ratio: 1;
  border-radius: 8px;
  border: 1px solid rgba(148,163,184,0.26);
  background: rgba(15,23,42,0.72);
  color: #fff;
  font-size: 1.25rem;
  line-height: 1;
  cursor: pointer;
}

.sidebar-avatar-option.selected {
  border-color: var(--warning);
  background: rgba(249,199,79,0.2);
}

.sidebar-full-btn {
  width: 100%;
  justify-content: center;
}

.sidebar-status {
  min-height: 1.2rem;
  margin: 0.7rem 0 0;
  color: rgba(226,232,240,0.78);
  font-size: 0.86rem;
  font-weight: 700;
}

.sidebar-status.success {
  color: #86efac;
}

.sidebar-status.error {
  color: #fecaca;
}

.sidebar-setting-button {
  width: 100%;
  min-height: 46px;
  display: grid;
  grid-template-columns: 24px 1fr auto;
  align-items: center;
  gap: 0.75rem;
  margin-top: 0.55rem;
  padding: 0.72rem 0.78rem;
  border-radius: 8px;
  border: 1px solid rgba(148,163,184,0.22);
  color: rgba(241,245,249,0.88);
  background: rgba(15,23,42,0.58);
  font: inherit;
  text-align: left;
  cursor: pointer;
}

.sidebar-setting-button.active {
  border-color: rgba(76,201,240,0.36);
  background: rgba(76,201,240,0.14);
}

.sidebar-setting-button.sidebar-setting-danger {
  border-color: rgba(249,65,68,0.28);
  background: rgba(249,65,68,0.12);
}

.sidebar-setting-button.sidebar-setting-danger i,
.sidebar-setting-button.sidebar-setting-danger strong {
  color: #fecaca;
}

.sidebar-setting-button strong {
  color: #fff;
  font-size: 0.82rem;
}

.sidebar-info-box {
  display: grid;
  gap: 0.35rem;
  padding: 0.85rem;
  border-radius: 8px;
  background: rgba(67,97,238,0.16);
  border: 1px solid rgba(125,211,252,0.18);
}

.sidebar-info-box strong {
  color: #fff;
}

.sidebar-info-box span {
  color: rgba(226,232,240,0.78);
  line-height: 1.5;
  font-size: 0.88rem;
}

/* ===== MAIN CONTAINER ===== */
.container {
  max-width: 1200px;
  margin: 2rem auto;
  padding: 0 1.5rem;
  width: 100%;
}

/* ===== DASHBOARD ===== */
.dashboard {
  background: var(--card-bg);
  border-radius: 20px;
  padding: 2.5rem;
  margin-bottom: 2rem;
  box-shadow: 0 10px 40px rgba(0,0,0,0.1);
}

.dashboard h2 {
  color: var(--primary);
  text-align: center;
  margin-bottom: 2rem;
  font-size: 1.8rem;
  font-weight: 700;
}

/* Welcome Row */
.welcome-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 2rem;
  flex-wrap: wrap;
  gap: 1rem;
}

.welcome-left {
  display: flex; align-items: center; gap: 1rem;
}

.welcome-avatar {
  font-size: 2.8rem;
  width: 60px; height: 60px;
  display: flex; align-items: center; justify-content: center;
}

.welcome-left h2 {
  margin: 0; text-align: left; font-size: 1.5rem;
}

.welcome-left p { color: var(--text-secondary); margin: 0; }

.welcome-left .home-tagline {
  margin-top: 0.3rem;
  color: var(--primary);
  font-weight: 800;
}

.welcome-actions {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  flex-wrap: wrap;
}

.btn-sm { padding: 0.6rem 1.2rem; font-size: 0.9rem; }

.referral-dashboard {
  border: 1px solid rgba(76,201,240,0.18);
}

.referral-header {
  display: flex;
  justify-content: space-between;
  gap: 1rem;
  align-items: flex-start;
  margin-bottom: 1.25rem;
}

.referral-header h2 {
  text-align: left;
  margin: 0.2rem 0 0.25rem;
}

.referral-header p {
  margin: 0;
  color: var(--text-secondary);
}

.referral-header-actions {
  display: flex;
  gap: 0.65rem;
  flex-wrap: wrap;
  justify-content: flex-end;
}

.referral-kicker {
  color: var(--secondary);
  font-size: 0.78rem;
  font-weight: 800;
  text-transform: uppercase;
}

.referral-grid {
  display: grid;
  grid-template-columns: minmax(220px, 0.8fr) minmax(260px, 1.2fr);
  gap: 1rem;
}

.referral-code-box,
.referral-link-box {
  display: grid;
  gap: 0.7rem;
  padding: 1rem;
  border-radius: 8px;
  border: 1px solid rgba(148,163,184,0.24);
  background: rgba(255,255,255,0.72);
}

body.dark .referral-code-box,
body.dark .referral-link-box {
  background: rgba(15,23,42,0.42);
}

.referral-code-box span,
.referral-link-box span {
  color: var(--text-secondary);
  font-size: 0.85rem;
  font-weight: 800;
  text-transform: uppercase;
}

.referral-code-box strong {
  color: var(--primary);
  font-size: 1.65rem;
  overflow-wrap: anywhere;
}

.referral-link-box p {
  margin: 0;
  color: var(--text-primary);
  overflow-wrap: anywhere;
  line-height: 1.45;
}

.referral-actions {
  display: flex;
  gap: 0.65rem;
  flex-wrap: wrap;
}

.referral-stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1rem;
  margin-top: 1rem;
}

.referral-success-note,
.referral-terms {
  margin-top: 1rem;
  padding: 0.85rem 1rem;
  border-radius: 8px;
  line-height: 1.55;
}

.referral-success-note {
  background: rgba(34,197,94,0.14);
  color: #166534;
  font-weight: 800;
}

body.dark .referral-success-note {
  color: #bbf7d0;
}

.referral-terms {
  background: rgba(67,97,238,0.1);
  color: var(--text-secondary);
  border: 1px solid rgba(67,97,238,0.14);
}

.referral-history {
  margin-top: 1.25rem;
}

.referral-history h3 {
  margin-bottom: 0.75rem;
  color: var(--primary);
}

.referral-history-item {
  display: flex;
  justify-content: space-between;
  gap: 1rem;
  padding: 0.85rem 0;
  border-top: 1px solid rgba(148,163,184,0.18);
}

.referral-history-item div {
  display: grid;
  gap: 0.15rem;
}

.referral-history-item span {
  color: var(--text-secondary);
  font-size: 0.85rem;
}

.referral-history-item.flagged {
  color: var(--danger);
}

/* Stats Grid */
.stats-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
  gap: 1.5rem;
}

.stat-card {
  background: linear-gradient(135deg, #1f72a2 0%, #dd0d45e0 100%);
  padding: 1.5rem;
  border-radius: 16px;
  text-align: center;
  border: 1px solid rgba(255,255,255,0.2);
  box-shadow: 0 4px 15px rgba(0,0,0,0.05);
  transition: all 0.3s;
  color: white;
}

.stat-card:hover { transform: translateY(-5px); box-shadow: 0 8px 25px rgba(0,0,0,0.1); }

.stat-number {
  font-size: 2.5rem;
  font-weight: 800;
  color: white;
  margin-bottom: 0.5rem;
}

/* ===== PERFORMANCE CHARTS ===== */
.charts-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(340px, 1fr));
  gap: 1.5rem;
  align-items: stretch;
}

.chart-container {
  background: var(--card-bg);
  border-radius: 20px;
  padding: 2rem;
  border: 1px solid rgba(255,255,255,0.2);
  box-shadow: 0 8px 25px rgba(0,0,0,0.08);
  width: 100%;
}

.chart-container h4 {
  font-size: 1rem;
  color: var(--text-secondary);
  margin-bottom: 1rem;
  text-align: center;
  font-weight: 600;
}

.chart-wrap {
  position: relative;
  height: 220px;
  width: 100%;
}

.chart-wrap canvas {
  width: 100% !important;
  height: 100% !important;
}

.chart-empty {
  display: flex;
  align-items: center;
  justify-content: center;
  height: 220px;
  color: var(--text-light);
  font-size: 0.9rem;
  text-align: center;
  flex-direction: column;
  gap: 0.5rem;
}

/* ===== CHAPTER GRID ===== */
.chapter-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(340px, 1fr));
  gap: 1.5rem;
  margin-bottom: 2rem;
}

.course-card {
  width: 100%;
  min-height: 230px;
  text-align: left;
  color: var(--text-primary);
  font: inherit;
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  justify-content: space-between;
}

.course-card-icon {
  width: 56px;
  height: 56px;
  border-radius: 16px;
  display: grid;
  place-items: center;
  color: #fff;
  background: linear-gradient(135deg, var(--primary), var(--accent));
  font-size: 1.6rem;
  box-shadow: 0 10px 24px rgba(67,97,238,0.22);
}

.course-card h3 {
  font-size: 1.5rem;
  margin: 0.25rem 0 0;
}

.course-card p {
  color: var(--text-secondary);
  margin: 0;
  min-height: 1.4rem;
}

.course-card-status {
  display: inline-flex;
  align-items: center;
  min-height: 1.8rem;
  padding: 0.35rem 0.7rem;
  border-radius: 999px;
  background: rgba(67,97,238,0.12);
  color: var(--primary);
  font-size: 0.82rem;
  font-weight: 700;
}

.course-card-status.empty-status {
  visibility: hidden;
}

.course-card-empty::before {
  background: linear-gradient(90deg, #94a3b8, #cbd5e1);
}

.course-card-empty .course-card-icon {
  background: linear-gradient(135deg, #64748b, #94a3b8);
  box-shadow: none;
}

.course-toolbar {
  grid-column: 1 / -1;
  background: var(--card-bg);
  border: 1px solid rgba(255,255,255,0.2);
  border-radius: 20px;
  padding: 1.25rem;
  display: flex;
  align-items: center;
  gap: 1rem;
  box-shadow: 0 8px 25px rgba(0,0,0,0.08);
}

.course-toolbar-copy {
  display: flex;
  flex-direction: column;
  gap: 0.2rem;
}

.course-toolbar-copy span {
  color: var(--text-light);
  font-size: 0.78rem;
  font-weight: 700;
  text-transform: uppercase;
}

.course-toolbar-copy h3 {
  margin: 0;
  color: var(--primary);
  font-size: 1.2rem;
}

.course-toolbar-copy p {
  margin: 0;
  color: var(--text-secondary);
  font-size: 0.92rem;
}

.course-empty-state {
  grid-column: 1 / -1;
  background: var(--card-bg);
  border: 1px dashed rgba(148,163,184,0.55);
  border-radius: 20px;
  padding: 3rem 1.5rem;
  text-align: center;
  color: var(--text-secondary);
  box-shadow: 0 8px 25px rgba(0,0,0,0.06);
}

.course-empty-state i {
  font-size: 2.4rem;
  color: var(--text-light);
  margin-bottom: 1rem;
}

.course-empty-state h3 {
  color: var(--text-primary);
  margin: 0;
}

.card {
  background: var(--card-bg);
  padding: 2rem;
  border-radius: 20px;
  cursor: pointer;
  transition: all 0.4s ease;
  border: 1px solid rgba(255,255,255,0.2);
  box-shadow: 0 8px 25px rgba(0,0,0,0.08);
  position: relative; overflow: hidden;
}

.card::before {
  content: '';
  position: absolute; top: 0; left: 0;
  width: 100%; height: 4px;
  background: linear-gradient(90deg, var(--primary), var(--primary-light));
}

.card:hover {
  transform: translateY(-8px) scale(1.02);
  box-shadow: 0 15px 40px rgba(0,0,0,0.15);
}

.chapter-number {
  position: absolute; top: 1rem; left: 1rem;
  background: var(--primary);
  color: white;
  width: 35px; height: 35px;
  border-radius: 50%;
  display: flex; align-items: center; justify-content: center;
  font-weight: 700; font-size: 1rem;
  box-shadow: 0 4px 12px rgba(67,97,238,0.3);
}

.chapter-info { margin-top: 1.5rem; }

.chapter-stats {
  display: flex; justify-content: space-between;
  margin-top: 1rem; padding-top: 1rem;
  border-top: 1px solid rgba(0,0,0,0.1);
}

.stat-item { text-align: center; font-size: 0.9rem; color: var(--text-secondary); }

.stat-value { display: block; font-weight: 700; color: var(--primary); font-size: 1.1rem; }

/* ===== LEADERBOARD ===== */
.leaderboard {
  background: var(--card-bg);
  border-radius: 20px;
  padding: 2rem;
  margin: 2rem 0;
  box-shadow: 0 10px 40px rgba(0,0,0,0.1);
}

.leaderboard-item {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 1rem 1.2rem;
  margin: 0.75rem 0;
  background: #4b5156;
  border-radius: 15px;
  transition: all 0.3s;
  color: white;
}

.leaderboard-item:hover { transform: translateX(5px); background: #23cdd9; }

/* Enhanced Leaderboard Rankings */
.lb-rank { font-size: 1.5rem; min-width: 40px; text-align: center; }
.lb-avatar { font-size: 1.5rem; margin: 0 0.75rem; }

.lb-info {
  flex: 1;
  display: flex; flex-direction: column;
  gap: 0.15rem;
}

.lb-info strong { font-size: 1rem; color: white; }
.lb-info span { font-size: 0.8rem; color: rgba(255,255,255,0.65); }

.lb-score {
  text-align: right;
  display: flex; flex-direction: column; gap: 0.15rem;
}

.lb-score strong { font-size: 1rem; color: var(--warning); }
.lb-score span { font-size: 0.8rem; color: rgba(255,255,255,0.65); }

/* Top-3 rank highlights */
.rank-1 { background: linear-gradient(135deg, #b7791f, #f6d860); }
.rank-2 { background: linear-gradient(135deg, #4a5568, #a0aec0); }
.rank-3 { background: linear-gradient(135deg, #7b341e, #dd6b20); }

/* ===== ADMIN DASHBOARD ===== */
.admin-panel {
  border: 1px solid rgba(67,97,238,0.18);
}

.admin-panel-header {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: 1rem;
  margin-bottom: 1.5rem;
}

.admin-panel-header h2 {
  margin-bottom: 0.4rem;
  text-align: left;
}

.admin-subtitle {
  color: var(--text-secondary);
  margin: 0;
}

.admin-actions {
  display: flex;
  gap: 0.75rem;
  align-items: center;
}

.admin-section {
  margin-top: 2rem;
}

.admin-section h3 {
  color: var(--primary);
  margin-bottom: 1rem;
}

.admin-empty {
  padding: 1.5rem;
  border-radius: 16px;
  background: rgba(67,97,238,0.08);
  color: var(--text-secondary);
  text-align: center;
}

.admin-attempt-card {
  background: rgba(255,255,255,0.65);
  border: 1px solid rgba(67,97,238,0.12);
  border-radius: 18px;
  padding: 1.25rem;
  margin: 0.9rem 0;
}

.admin-attempt-card.flagged {
  border-color: rgba(249,65,68,0.35);
  box-shadow: 0 10px 24px rgba(249,65,68,0.12);
}

body.dark .admin-attempt-card {
  background: rgba(15,23,42,0.78);
}

.admin-withdrawal-card {
  display: grid;
  gap: 0.9rem;
}

.admin-withdrawal-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 0.65rem 1rem;
}

.admin-withdrawal-grid span {
  color: var(--text-secondary);
  display: block;
  font-size: 0.82rem;
  margin-bottom: 0.12rem;
}

.admin-withdrawal-actions {
  display: flex;
  justify-content: flex-end;
}

.admin-attempt-head {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: 1rem;
  margin-bottom: 0.9rem;
}

.admin-attempt-score {
  display: flex;
  flex-direction: column;
  align-items: flex-end;
  gap: 0.4rem;
}

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

.admin-chip-row {
  display: flex;
  flex-wrap: wrap;
  gap: 0.6rem;
  margin: 0.8rem 0;
}

.admin-chip {
  background: rgba(67,97,238,0.1);
  color: var(--text-primary);
  border-radius: 999px;
  padding: 0.4rem 0.8rem;
  font-size: 0.88rem;
  font-weight: 600;
}

.admin-chip.danger {
  background: rgba(249,65,68,0.14);
  color: var(--danger);
}

.admin-chip.success {
  background: rgba(76,201,240,0.16);
  color: #0369a1;
}

body.dark .admin-chip {
  background: rgba(148,163,184,0.14);
}

body.dark .admin-chip.success {
  color: #7dd3fc;
}

.admin-question-times {
  color: var(--text-secondary);
  font-size: 0.9rem;
  line-height: 1.6;
}

.admin-user-list .leaderboard-item,
.admin-leaderboard-list .leaderboard-item {
  margin: 0.6rem 0;
}

.admin-recording-list {
  display: grid;
  gap: 0.9rem;
}

.admin-recording-user {
  border: 1px solid rgba(67,97,238,0.14);
  border-radius: 8px;
  padding: 0.9rem;
  background: rgba(255,255,255,0.5);
}

body.dark .admin-recording-user {
  background: rgba(15,23,42,0.55);
}

.admin-recording-user > summary,
.admin-recording-chapter > summary,
.admin-recording-part > summary {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 1rem;
  cursor: pointer;
  list-style: none;
}

.admin-recording-user > summary::-webkit-details-marker,
.admin-recording-chapter > summary::-webkit-details-marker,
.admin-recording-part > summary::-webkit-details-marker {
  display: none;
}

.admin-recording-user-main {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  min-width: 0;
}

.admin-recording-user-main span:last-child {
  display: grid;
  gap: 0.15rem;
  min-width: 0;
}

.admin-recording-user-main small {
  color: var(--text-secondary);
  font-size: 0.84rem;
}

.admin-recording-chapters {
  display: grid;
  gap: 0.75rem;
  margin-top: 0.85rem;
}

.admin-recording-parts {
  display: grid;
  gap: 0.65rem;
  margin-top: 0.75rem;
  padding-left: 0.65rem;
}

.admin-recording-chapter {
  border-top: 1px solid rgba(148,163,184,0.18);
  padding-top: 0.75rem;
}

.admin-recording-part {
  border-left: 2px solid rgba(67,97,238,0.28);
  padding-left: 0.75rem;
}

.admin-recording-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 0.8rem;
  margin-top: 0.75rem;
}

.admin-recording-card {
  border: 1px solid rgba(148,163,184,0.2);
  border-radius: 8px;
  padding: 0.75rem;
  background: rgba(255,255,255,0.56);
}

body.dark .admin-recording-card {
  background: rgba(2,6,23,0.28);
}

.admin-recording-video {
  display: block;
  width: 100%;
  aspect-ratio: 16 / 9;
  border-radius: 8px;
  background: #020617;
}

.admin-recording-meta {
  display: grid;
  gap: 0.2rem;
  margin-top: 0.65rem;
}

.admin-recording-meta span {
  color: var(--text-secondary);
  font-size: 0.88rem;
  line-height: 1.45;
}

.admin-recording-actions {
  margin-top: 0.65rem;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.65rem;
}

.admin-recording-link {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  color: var(--primary);
  font-weight: 700;
  text-decoration: none;
}

.admin-recording-state {
  min-height: 8.5rem;
  justify-content: center;
  padding: 0.75rem;
  border: 1px dashed rgba(148,163,184,0.38);
  border-radius: 8px;
  background: rgba(148,163,184,0.08);
}

/* ===== DIFFICULTY BADGE (in quiz) ===== */
.difficulty-badge {
  background: linear-gradient(135deg, var(--info), #a855f7);
  color: white;
  padding: 0.4rem 1rem;
  border-radius: 20px;
  font-size: 0.85rem;
  font-weight: 600;
}

.difficulty-badge.easy { background: linear-gradient(135deg, #059669, #34d399); }
.difficulty-badge.medium { background: linear-gradient(135deg, #d97706, #fbbf24); }
.difficulty-badge.hard { background: linear-gradient(135deg, #dc2626, #f87171); }
.difficulty-badge.all { background: linear-gradient(135deg, var(--info), #a855f7); }

/* ===== QUIZ ===== */
.quiz {
  background: var(--card-bg);
  border-radius: 25px;
  padding: 2.5rem;
  margin: 2rem 0;
  box-shadow: 0 15px 50px rgba(0,0,0,0.1);
}

.timer-container {
  display: flex; justify-content: space-between; align-items: center;
  margin-bottom: 2rem; padding: 1rem;
  background: linear-gradient(135deg, #f8fafc 0%, #ffffff 100%);
  border-radius: 15px;
  border: 1px solid rgba(0,0,0,0.05);
}

body.dark .timer-container { background: rgba(15,23,42,0.8); }

.recording-panel {
  display: flex;
  align-items: center;
  gap: 0.9rem;
  margin-bottom: 1rem;
  padding: 0.85rem;
  border-radius: 14px;
  background: rgba(15,23,42,0.82);
  border: 1px solid rgba(148,163,184,0.22);
}

.recording-preview {
  width: 128px;
  aspect-ratio: 4 / 3;
  flex: 0 0 auto;
  object-fit: cover;
  border-radius: 10px;
  background: #020617;
  border: 1px solid rgba(255,255,255,0.14);
}

.recording-copy {
  display: grid;
  gap: 0.2rem;
  min-width: 0;
  color: var(--text-secondary);
  font-size: 0.88rem;
  line-height: 1.35;
}

.recording-copy strong {
  color: var(--text-primary);
  font-size: 0.95rem;
}

.recording-warning {
  min-height: 1.2em;
  color: #fecaca;
  font-weight: 700;
}

.camera-start-warning {
  min-height: 1.2em;
  margin: 0.8rem 0;
  color: #fecaca;
  font-weight: 700;
  line-height: 1.4;
}

.recording-upload-summary {
  margin-bottom: 1rem;
  padding: 0.9rem 1rem;
  border-radius: 14px;
  background: rgba(59,130,246,0.12);
  border: 1px solid rgba(96,165,250,0.28);
  color: var(--text-secondary);
  line-height: 1.5;
}

.recording-upload-summary strong {
  color: var(--text-primary);
}

.recording-upload-instruction {
  margin: 0.45rem 0;
  color: #bfdbfe;
  font-weight: 700;
}

.admin-merge-note {
  color: var(--text-secondary);
  font-size: 0.9rem;
  font-weight: 700;
}

.admin-merge-note.error {
  color: #fecaca;
}

.pre-quiz-recording-modal {
  z-index: 9000;
  align-items: stretch;
  overflow: hidden;
}

.pre-quiz-recording-card {
  max-width: 680px;
  max-height: min(88dvh, 760px);
  margin: auto;
  text-align: left;
  display: flex;
  flex-direction: column;
  overflow: hidden;
}

.pre-quiz-recording-head {
  display: flex;
  align-items: flex-start;
  gap: 1rem;
  margin-bottom: 1rem;
  flex: 0 0 auto;
}

.pre-quiz-recording-icon {
  width: 48px;
  height: 48px;
  display: grid;
  place-items: center;
  flex: 0 0 auto;
  border-radius: 12px;
  color: #fff;
  background: linear-gradient(135deg, var(--primary), var(--primary-light));
  font-size: 1.15rem;
}

.pre-quiz-recording-card h2 {
  margin-bottom: 0.25rem;
  text-align: left;
}

.pre-quiz-instructions h3 {
  margin: 1rem 0 0.5rem;
  color: var(--text-primary);
  font-size: 1rem;
}

.pre-quiz-instructions {
  color: var(--text-secondary);
  line-height: 1.6;
  min-height: 0;
  overflow-y: auto;
  padding-right: 0.35rem;
}

.pre-quiz-instructions p {
  margin-bottom: 0.85rem;
}

.pre-quiz-instructions ul {
  display: grid;
  gap: 0.55rem;
  padding-left: 1.25rem;
  margin: 0 0 1rem;
}

.pre-quiz-instructions li::marker {
  color: var(--primary-light);
}

.pre-quiz-agreement {
  padding: 0.85rem 1rem;
  border-radius: 10px;
  color: var(--text-primary);
  background: rgba(67,97,238,0.12);
  border: 1px solid rgba(67,97,238,0.22);
  font-weight: 700;
}

.pre-quiz-recording-actions {
  display: flex;
  justify-content: flex-end;
  gap: 0.75rem;
  flex-wrap: wrap;
  margin-top: 1rem;
  padding-top: 1rem;
  flex: 0 0 auto;
  border-top: 1px solid rgba(148,163,184,0.18);
  background: var(--card-bg);
}

.quiz-scoring-modal {
  z-index: 9200;
}

.quiz-scoring-card {
  max-width: 520px;
  text-align: center;
}

.quiz-scoring-icon {
  width: 58px;
  height: 58px;
  display: grid;
  place-items: center;
  margin: 0 auto 1rem;
  border-radius: 16px;
  color: #fff;
  background: linear-gradient(135deg, #22c55e, var(--primary));
  font-size: 1.35rem;
}

.quiz-scoring-rules {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 0.85rem;
  margin: 1.25rem 0 1.35rem;
}

.quiz-scoring-rule {
  min-height: 116px;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 0.4rem;
  padding: 1rem;
  border-radius: 12px;
  border: 1px solid rgba(255,255,255,0.14);
  background: rgba(255,255,255,0.06);
}

.quiz-scoring-rule span {
  font-size: 2rem;
  font-weight: 900;
  line-height: 1;
}

.quiz-scoring-rule p {
  margin: 0;
  color: var(--text-secondary);
  font-weight: 700;
  line-height: 1.35;
}

.quiz-scoring-rule-correct span {
  color: var(--success);
}

.quiz-scoring-rule-incorrect span {
  color: var(--danger);
}

.quiz-scoring-start {
  width: 100%;
}

.rule-warning-modal {
  position: fixed;
  inset: 0;
  z-index: 9500;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 1rem;
  background: rgba(2,6,23,0.58);
  backdrop-filter: blur(8px);
}

.rule-warning-card {
  width: min(520px, 100%);
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 1rem;
  padding: 1.35rem;
  border-radius: 12px;
  color: var(--text-primary);
  background: var(--card-bg);
  border: 1px solid rgba(255,255,255,0.16);
  box-shadow: 0 24px 70px rgba(2,6,23,0.34);
}

.rule-warning-icon {
  width: 46px;
  height: 46px;
  display: grid;
  place-items: center;
  border-radius: 12px;
  color: #fff;
  background: var(--warning);
  font-size: 1.15rem;
}

.rule-warning-card h3 {
  margin-bottom: 0.45rem;
}

.rule-warning-card p {
  color: var(--text-secondary);
  line-height: 1.55;
  margin-bottom: 1rem;
}

.timer {
  font-size: 1.4rem; font-weight: 700; color: var(--primary);
  display: flex; align-items: center; gap: 0.5rem;
}

.timer.warning { color: var(--warning); animation: pulse 1s infinite; }
.timer.danger { color: var(--danger); animation: pulse 0.5s infinite; }

@keyframes pulse { 0%, 100% { opacity: 1; } 50% { opacity: 0.6; } }

.question-counter { font-size: 1.1rem; font-weight: 700; color: var(--text-secondary); }

.progress-container { width: 100%; margin: 1.5rem 0; }

.progress-bar {
  width: 100%; height: 12px;
  background: #e2e8f0; border-radius: 10px;
  overflow: hidden; position: relative;
}

.progress {
  height: 100%;
  background: linear-gradient(90deg, var(--primary), var(--primary-light));
  border-radius: 10px; transition: width 0.3s;
  position: relative;
}

.progress::after {
  content: '';
  position: absolute; inset: 0;
  background: linear-gradient(90deg, transparent, rgba(255,255,255,0.3), transparent);
  animation: shimmer 2s infinite;
}

@keyframes shimmer {
  0% { transform: translateX(-100%); }
  100% { transform: translateX(100%); }
}

.question-container {
  background: white;
  padding: 2.5rem; border-radius: 20px;
  margin-bottom: 2rem;
  box-shadow: 0 5px 20px rgba(0,0,0,0.05);
  border: 1px solid rgba(0,0,0,0.05);
}

body.dark .question-container { background: rgba(15,23,42,0.9); }

.quiz-question-image {
  display: block;
  max-width: min(100%, 760px);
  max-height: 420px;
  width: auto;
  height: auto;
  margin: 1rem auto;
  border-radius: 8px;
  object-fit: contain;
}

#qText mjx-container,
.option mjx-container {
  max-width: 100%;
  overflow-x: auto;
  overflow-y: hidden;
}

#qText table,
.option table {
  width: max-content;
  max-width: 100%;
  margin: 1rem auto;
  border-collapse: collapse;
  overflow-x: auto;
  display: block;
}

#qText th,
#qText td,
.option th,
.option td {
  border: 1px solid rgba(148, 163, 184, 0.45);
  padding: 0.5rem 0.7rem;
  text-align: center;
  vertical-align: middle;
}

#qText th,
.option th {
  font-weight: 700;
}

.quiz-button-panel {
  display: flex;
  flex-direction: column;
  gap: 1rem;
  margin-bottom: 1.5rem;
}

.quiz-button-panel .actions,
.quiz-button-panel .nav-grid {
  margin: 0;
}

.option-grid { display: grid; grid-template-columns: 1fr; gap: 1rem; }

.option {
  background: #f8fafc; padding: 1.5rem; border-radius: 15px;
  cursor: pointer; transition: all 0.3s;
  border: 2px solid transparent; font-weight: 500;
}

body.dark .option { background: rgba(255,255,255,0.05); color: var(--text-primary); }

.option:hover { background: #7f8379; transform: translateX(5px); }
.option.selected { background: var(--primary); color: white; border-color: var(--primary-light); box-shadow: 0 4px 15px rgba(67,97,238,0.3); }
.option.correct { background: #22c55e; color: white; border-color: #16a34a; }
.option.incorrect { background: var(--danger); color: white; border-color: #ef4444; }
.option.disabled { cursor: not-allowed; opacity: 0.7; }

/* Nav Grid */
.nav-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(40px, 1fr));
  gap: 0.8rem; margin: 1rem 0;
}

.nav-btn {
  padding: 1rem; border: none; border-radius: 12px;
  background: #1f1e1e; color: white; cursor: pointer;
  transition: all 0.3s; font-weight: 600;
  position: relative; overflow: hidden;
}

.nav-btn:hover { background: #059ef0; transform: translateY(-2px); }
.nav-btn.answered { background: var(--success); color: #0b0b0b; }
.nav-btn.skipped { background: #64748b; color: #fff; }
.nav-btn.marked { background: var(--warning); color: #000; }
.nav-btn.current { border: 3px solid var(--primary); box-shadow: 0 0 0 3px rgba(67,97,238,0.2); }
.nav-btn:disabled { opacity: 0.55; cursor: not-allowed; transform: none; }
.nav-btn:disabled:hover { background: #6b7280; transform: none; }

/* Buttons */
.btn {
  padding: 1rem 2rem; border: none; border-radius: 15px;
  font-weight: 600; cursor: pointer; transition: all 0.3s;
  display: inline-flex; align-items: center; gap: 0.5rem;
  font-size: 1rem;
}

.btn-primary {
  background: linear-gradient(135deg, var(--primary) 0%, var(--primary-light) 100%);
  color: white;
  box-shadow: 0 4px 15px rgba(67,97,238,0.3);
}

.btn-primary:hover { transform: translateY(-3px); box-shadow: 0 8px 25px rgba(67,97,238,0.4); }
.btn-secondary { background: var(--warning); color: white; }
.btn-google {
  background: #ffffff;
  color: #1f2937;
  box-shadow: 0 4px 15px rgba(15,23,42,0.18);
}
.btn-google i {
  color: #ea4335;
}
.btn-google:hover {
  transform: translateY(-3px);
  box-shadow: 0 8px 25px rgba(15,23,42,0.28);
}
.btn-success { background: var(--success); color: white; }
.btn-danger { background: var(--danger); color: white; }
.btn:disabled { opacity: 0.6; cursor: not-allowed; transform: none !important; }

.actions {
  display: flex; justify-content: center; flex-wrap: wrap;
  gap: 1rem; margin: 1rem 0 0;
}

/* ===== RESULT ===== */
.result-container {
  background: var(--card-bg);
  border-radius: 25px; padding: 3rem;
  margin: 2rem 0;
  box-shadow: 0 15px 50px rgba(0,0,0,0.1);
  text-align: center;
  color: var(--text-primary);
}

.result-top-actions {
  position: sticky;
  top: 84px;
  z-index: 90;
  display: flex;
  justify-content: flex-start;
  margin: -1.5rem -1.5rem 1.5rem;
  padding: 0.75rem;
  border-radius: 16px;
  background: rgba(15,23,42,0.86);
  border: 1px solid rgba(255,255,255,0.12);
  backdrop-filter: blur(14px);
}

body:not(.dark) .result-top-actions {
  background: rgba(255,255,255,0.9);
}

.score-display {
  font-size: 3rem; font-weight: 800; color: var(--primary);
  margin: 2rem 0;
  background: linear-gradient(135deg, var(--primary), var(--primary-light));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.review-section { margin: 2rem 0; }

.review-item {
  background: #f8fafc; padding: 2rem;
  margin: 1.5rem 0; border-radius: 20px;
  text-align: left;
  border-left: 4px solid var(--text-light);
  transition: all 0.3s;
  color: var(--text-primary);
}

body.dark .review-item { background: rgba(15,23,42,0.8); }

.review-item p,
.review-item strong {
  color: var(--text-primary);
}

.review-item:hover { transform: translateX(5px); box-shadow: 0 5px 20px rgba(0,0,0,0.1); }
.review-item.correct { border-left-color: var(--success); }
.review-item.incorrect { border-left-color: var(--danger); }
.review-item.unattempted { border-left-color: var(--warning); }

.solution {
  background: white; padding: 1.5rem; margin-top: 1rem;
  border-radius: 15px; border-left: 3px solid var(--info);
  font-style: italic;
  color: var(--text-primary);
}

body.dark .solution { background: rgba(15,23,42,0.8); }

/* ===== ANIMATIONS ===== */
@keyframes fadeInUp {
  from { opacity: 0; transform: translateY(30px); }
  to { opacity: 1; transform: translateY(0); }
}

@keyframes slideInLeft {
  from { opacity: 0; transform: translateX(-30px); }
  to { opacity: 1; transform: translateX(0); }
}

@keyframes bounceIn {
  0% { opacity: 0; transform: scale(0.7); }
  60% { opacity: 1; transform: scale(1.05); }
  80% { transform: scale(0.97); }
  100% { opacity: 1; transform: scale(1); }
}

/* Confetti */
.confetti {
  position: fixed; width: 10px; height: 10px;
  opacity: 0; animation: confetti-fall 2s ease-out;
}

@keyframes confetti-fall {
  0% { opacity: 1; transform: translateY(-100vh) rotate(0deg); }
  100% { opacity: 0; transform: translateY(100vh) rotate(720deg); }
}

/* Points notification */
.points-notification {
  position: fixed; top: 90px; right: 20px; z-index: 9000;
  padding: 1rem 1.5rem; border-radius: 15px;
  font-weight: 700; font-size: 1rem;
  display: flex; align-items: center; gap: 0.5rem;
  box-shadow: 0 8px 25px rgba(0,0,0,0.2);
  animation: fadeInOut 2.5s ease-in-out;
}

.points-notification.points-added { background: #22c55e; color: white; }
.points-notification.points-lost { background: var(--danger); color: white; }

@keyframes fadeInOut {
  0% { opacity: 0; transform: translateY(-20px); }
  15% { opacity: 1; transform: translateY(0); }
  80% { opacity: 1; }
  100% { opacity: 0; transform: translateY(-20px); }
}

/* ===== UTILITY ===== */
.text-center { text-align: center; }
.mb-1 { margin-bottom: 0.5rem; }
.mb-2 { margin-bottom: 1rem; }
.mb-3 { margin-bottom: 1.5rem; }
.mt-2 { margin-top: 1rem; }
.mt-3 { margin-top: 1.5rem; }

.chapter-title { color: var(--primary); font-size: 1.2rem; }

/* Glass helper */
.glass {
  background: var(--glass-bg);
  backdrop-filter: var(--glass-blur);
  -webkit-backdrop-filter: var(--glass-blur);
  border: 1px solid var(--glass-border);
  box-shadow: var(--glass-shadow);
}

/* ===== RESPONSIVE ===== */
@media (min-width: 1025px) {
  .container.quiz {
    max-width: min(1680px, calc(100% - 4rem));
    margin: 2rem auto;
  }
}

@media (max-width: 1024px) {
  .header {
    padding: 0.9rem 1.25rem;
  }

  .container {
    margin: 1.5rem auto;
    padding: 0 1.25rem;
  }

  .dashboard,
  .quiz,
  .result-container,
  .leaderboard,
  .chart-container {
    padding: 2rem;
  }

  .chapter-grid {
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  }

  .stats-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .referral-grid {
    grid-template-columns: 1fr;
  }

  .timer-container {
    gap: 1rem;
    flex-wrap: wrap;
  }

  .actions .btn {
    flex: 1 1 220px;
    justify-content: center;
  }
}

@media (max-width: 768px) {
  .header { padding: 0.8rem 1rem; }
  .header-content {
    align-items: stretch;
  }
  .logo span { display: none; }
  .header-right {
    gap: 0.5rem;
    width: 100%;
    justify-content: space-between;
  }
  .user-profile-pill span:last-child { display: none; }
  .withdraw-actions {
    flex-direction: column;
  }
  .withdraw-grid,
  .admin-withdrawal-grid {
    grid-template-columns: 1fr;
  }
  .container {
    margin: 1rem auto 1.5rem;
    padding: 0 1rem;
  }
  .dashboard,
  .quiz,
  .result-container,
  .leaderboard,
  .chart-container,
  .card {
    padding: 1.5rem;
    border-radius: 18px;
  }
  .chapter-grid { grid-template-columns: 1fr; }
  .stats-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .referral-header,
  .referral-history-item {
    flex-direction: column;
  }
  .referral-stats {
    grid-template-columns: 1fr;
  }
  .referral-actions .btn,
  .referral-header-actions,
  .referral-header .btn {
    width: 100%;
    justify-content: center;
  }
  .charts-grid { grid-template-columns: 1fr; }
  .chart-wrap { height: 180px; }
  .nav-grid { grid-template-columns: repeat(auto-fit, minmax(35px, 1fr)); }
  .question-container { padding: 1.5rem; }
  .result-top-actions {
    top: 112px;
    margin: -0.75rem -0.75rem 1rem;
    border-radius: 12px;
  }
  .timer-container {
    flex-direction: column;
    align-items: stretch;
  }
  .timer-container > div:last-child {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 0.75rem;
  }
  .actions { flex-direction: column; }
  .actions .btn {
    flex: 0 0 auto;
    min-height: 44px;
    padding: 0.85rem 1rem;
  }
  .btn { width: 100%; justify-content: center; }
  .difficulty-grid { grid-template-columns: 1fr 1fr; }
  .login-overlay {
    align-items: flex-start;
    padding: 1rem;
  }
  .login-card {
    padding: 2rem 1.5rem;
    margin: auto;
  }
  .avatar-grid { grid-template-columns: repeat(6, 1fr); }
  .welcome-row { flex-direction: column; align-items: flex-start; }
  .welcome-left {
    width: 100%;
  }
  .welcome-actions {
    width: 100%;
  }
  .admin-panel-header,
  .admin-attempt-head {
    flex-direction: column;
  }
  .admin-attempt-score {
    align-items: flex-start;
  }
  .points-notification {
    left: 1rem;
    right: 1rem;
    top: 80px;
    width: auto;
  }
  .recording-panel {
    align-items: flex-start;
  }
  .recording-preview {
    width: 104px;
  }
}

@media (max-width: 560px) {
  .header-right {
    justify-content: center;
  }

  .user-profile-pill,
  .withdraw-btn,
  .wallet {
    width: 100%;
    justify-content: center;
  }

  .stats-grid,
  .difficulty-grid {
    grid-template-columns: 1fr;
  }

  .avatar-grid {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .login-card {
    padding: 1.5rem 1rem;
  }

  .login-logo .login-icon {
    width: 68px;
    height: 68px;
    font-size: 2rem;
  }

  .login-logo h1 {
    font-size: 1.6rem;
  }

  .dashboard,
  .quiz,
  .result-container,
  .leaderboard,
  .chart-container,
  .card,
  .question-container,
  .review-item {
    padding: 1.2rem;
  }

  .chart-wrap {
    height: 160px;
  }

  .recording-panel {
    flex-direction: column;
  }

  .recording-preview {
    width: min(100%, 180px);
  }

  .home-section-tab {
    top: 0.75rem;
    right: 0.75rem;
    bottom: 0.75rem;
    left: 0.75rem;
    width: auto;
    max-height: none;
    transform: translateY(16px);
  }

  .home-section-tab.open {
    transform: translateY(0);
  }

  .home-section-tab-header,
  .home-section-tab-body {
    padding: 1rem;
  }

  .pre-quiz-recording-modal {
    padding: 0.75rem;
  }

  .pre-quiz-recording-card {
    max-height: calc(100dvh - 1.5rem);
    padding: 1rem;
  }

  .pre-quiz-recording-head {
    gap: 0.75rem;
  }

  .pre-quiz-recording-icon {
    width: 42px;
    height: 42px;
  }

  .pre-quiz-recording-actions .btn {
    width: 100%;
  }

  .quiz-scoring-card {
    padding: 1.25rem;
  }

  .quiz-scoring-rules {
    grid-template-columns: 1fr;
  }

  .timer {
    font-size: 1.2rem;
  }

  .question-counter {
    font-size: 1rem;
  }

  .option {
    padding: 1rem;
  }

  .nav-grid {
    grid-template-columns: repeat(auto-fit, minmax(40px, 1fr));
  }
}

@media (max-width: 400px) {
  .container {
    padding: 0 0.75rem;
  }

  .header {
    padding: 0.75rem;
  }

  .avatar-grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .difficulty-grid {
    grid-template-columns: 1fr;
  }
}

@media print {
  body * {
    visibility: hidden !important;
  }

  body::before {
    content: "Quiz screen capture is blocked.";
    visibility: visible !important;
    position: fixed;
    inset: 0;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 2rem;
    color: #111827;
    background: #ffffff;
    font-size: 24px;
    font-weight: 700;
    text-align: center;
  }
}