:root {
  --bg: #0b1220;
  --bg-2: #0f1728;
  --bg-3: #09101c;

  --panel: rgba(17, 26, 43, 0.95);
  --panel-2: #17233a;
  --panel-3: rgba(23, 35, 58, 0.82);

  --text: #e8eefc;
  --muted: #a8b3cf;

  --accent: #4ea1ff;
  --accent-2: #7cc4ff;
  --accent-soft: rgba(78, 161, 255, 0.12);
  --accent-ring: rgba(78, 161, 255, 0.12);

  --line: #24314f;
  --line-soft: rgba(255, 255, 255, 0.08);
  --line-strong: rgba(124, 196, 255, 0.22);

  --success: #4caf50;
  --danger: #f44336;
  --warning: #ff9800;
  --gold: #ffd54a;

  --shadow: 0 14px 40px rgba(0, 0, 0, 0.35);
  --shadow-soft: 0 10px 26px rgba(0, 0, 0, 0.22);
  --shadow-glow: 0 18px 50px rgba(78, 161, 255, 0.14);

  --radius-xl: 28px;
  --radius-lg: 24px;
  --radius-md: 18px;
  --radius-sm: 12px;
  --radius-xs: 10px;

  --transition-fast: 0.18s ease;
  --transition-mid: 0.28s ease;
}

/* =========================
   RESET / BASE
========================= */

*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  margin: 0;
  min-height: 100vh;
  overflow-x: hidden;
  font-family: Arial, Helvetica, sans-serif;
  line-height: 1.6;
  color: var(--text);
  background:
    radial-gradient(circle at top, rgba(78, 161, 255, 0.08), transparent 28%),
    linear-gradient(180deg, #09101c 0%, #0d1524 100%);
}

body.app-ready .hero,
body.app-ready .section,
body.app-ready .footer {
  animation: pageFadeIn 0.7s ease;
}

img,
canvas,
iframe,
video {
  max-width: 100%;
}

button,
input,
select,
textarea {
  font: inherit;
}

a {
  color: inherit;
  text-decoration: none;
}

.hidden,
.is-hidden {
  display: none !important;
}

.container {
  width: min(1120px, calc(100% - 32px));
  margin: 0 auto;
}

main {
  display: block;
}

/* =========================
   TYPOGRAPHY / COMMON
========================= */

.page-title {
  padding: 42px 0 12px;
}

.page-title h1 {
  margin: 0 0 8px;
  font-size: 2.3rem;
  letter-spacing: -0.02em;
}

.page-title p {
  margin: 0;
  color: var(--muted);
  font-size: 1rem;
}

.section {
  padding: 32px 0 54px;
}

.section h2 {
  margin: 0 0 10px;
  font-size: 1.9rem;
  line-height: 1.15;
  letter-spacing: -0.02em;
}

.section p.section-sub {
  margin: 0 0 24px;
  color: var(--muted);
}

.controls-section {
  padding-top: 0;
  padding-bottom: 12px;
}

.pinned-section {
  padding-top: 12px;
}

.back-link {
  display: inline-block;
  margin-bottom: 18px;
  color: var(--accent-2);
  font-weight: 700;
  transition: color var(--transition-fast);
}

.back-link:hover {
  color: var(--text);
}

.muted-text {
  color: var(--muted);
}

.code-inline {
  display: inline-block;
  padding: 2px 8px;
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.06);
  border: 1px solid var(--line-soft);
  font-size: 0.9rem;
}

.empty-state {
  padding: 18px;
  border-radius: 18px;
  border: 1px dashed var(--line-soft);
  color: var(--muted);
  background: rgba(255, 255, 255, 0.02);
}

/* =========================
   HEADER / NAV
========================= */

header,
.site-header {
  position: sticky;
  top: 0;
  z-index: 1000;
  border-bottom: 1px solid var(--line-soft);
  background: rgba(9, 16, 28, 0.88);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
}

.nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 16px 0;
}

.brand {
  font-size: 1.3rem;
  font-weight: 900;
  letter-spacing: 0.3px;
  white-space: nowrap;
}

.brand span {
  color: var(--accent-2);
}

.topbar-right {
  display: flex;
  align-items: center;
  gap: 10px;
  flex-wrap: wrap;
}

.nav-links {
  display: flex;
  flex-wrap: wrap;
  gap: 18px;
  color: var(--muted);
  font-size: 0.96rem;
}

.nav-links a {
  position: relative;
  transition: color var(--transition-fast);
}

.nav-links a:hover {
  color: var(--text);
}

.nav-links a.active {
  color: var(--accent-2);
  font-weight: 700;
}

.nav-links a.active::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: -8px;
  height: 2px;
  border-radius: 999px;
  background: linear-gradient(90deg, var(--accent), var(--accent-2));
  opacity: 0.95;
}

.user-email-display {
  max-width: 180px;
  color: var(--muted);
  font-size: 0.88rem;
  line-height: 1.35;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.top-profile-avatar {
  width: 40px;
  height: 40px;
  min-width: 40px;
  border-radius: 50%;
  overflow: hidden;
  border: 2px solid rgba(78, 161, 255, 0.34);
  background: rgba(255, 255, 255, 0.05);
  box-shadow: 0 8px 18px rgba(0, 0, 0, 0.2);
}

.top-profile-avatar img {
  width: 100%;
  height: 100%;
  display: block;
  object-fit: cover;
}

/* =========================
   HERO
========================= */

.hero {
  position: relative;
  padding: 76px 0 46px;
}

.hero::before {
  content: "";
  position: absolute;
  top: -120px;
  left: 50%;
  transform: translateX(-50%);
  width: min(600px, 90vw);
  height: min(600px, 90vw);
  background: radial-gradient(circle, rgba(78, 161, 255, 0.15), transparent 60%);
  z-index: -1;
  pointer-events: none;
}

.hero h1 {
  margin: 0 0 14px;
  max-width: 900px;
  font-size: clamp(2.1rem, 5vw, 4rem);
  line-height: 1.06;
  letter-spacing: -0.02em;
}

.hero p {
  margin: 0;
  max-width: 720px;
  color: var(--muted);
  font-size: 1.05rem;
}

.rank-badge {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 34px;
  padding: 8px 14px;
  border-radius: 999px;
  margin-bottom: 12px;
  background: rgba(255, 213, 74, 0.08);
  border: 1px solid rgba(255, 213, 74, 0.18);
  color: #ffe588;
  font-size: 0.88rem;
  font-weight: 800;
}

.hero-actions {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
  align-items: center;
}

.hero-action-btn {
  min-width: 220px;
  width: auto;
  flex: 0 0 auto;
  padding-left: 18px;
  padding-right: 18px;
}

/* =========================
   BADGES
========================= */

.badge {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 32px;
  padding: 6px 12px;
  border-radius: 999px;
  margin-bottom: 12px;
  background: var(--accent-soft);
  border: 1px solid rgba(124, 196, 255, 0.25);
  color: var(--accent-2);
  font-size: 0.84rem;
  font-weight: 700;
  line-height: 1.2;
}

.badge-gold {
  background: rgba(255, 213, 74, 0.12);
  border: 1px solid rgba(255, 213, 74, 0.35);
  color: #ffd54a;
}

.badge-silver {
  background: rgba(210, 220, 235, 0.12);
  border: 1px solid rgba(210, 220, 235, 0.35);
  color: #d2dceb;
}

.badge-bronze {
  background: rgba(205, 127, 50, 0.12);
  border: 1px solid rgba(205, 127, 50, 0.35);
  color: #cd7f32;
}

/* =========================
   BUTTONS
========================= */

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  min-height: 48px;
  padding: 11px 16px;
  border-radius: var(--radius-sm);
  border: 1px solid var(--line);
  background: var(--panel-2);
  color: var(--text);
  font-weight: 700;
  cursor: pointer;
  box-shadow: 0 6px 18px rgba(0, 0, 0, 0.14);
  transition:
    transform var(--transition-fast),
    border-color var(--transition-fast),
    color var(--transition-fast),
    box-shadow var(--transition-fast),
    background var(--transition-fast),
    filter var(--transition-fast);
}

.btn:hover {
  border-color: var(--accent);
  color: var(--accent-2);
  transform: translateY(-1px);
  box-shadow: 0 10px 24px rgba(0, 0, 0, 0.22);
}

.btn:active {
  transform: scale(0.97);
}

.btn-primary {
  border: none;
  background: linear-gradient(135deg, var(--accent), var(--accent-2));
  color: #04101f;
  box-shadow:
    0 10px 26px rgba(78, 161, 255, 0.22),
    inset 0 1px 0 rgba(255, 255, 255, 0.22);
}

.btn-primary:hover {
  color: #04101f;
  filter: brightness(1.03);
  box-shadow:
    0 14px 30px rgba(78, 161, 255, 0.28),
    inset 0 1px 0 rgba(255, 255, 255, 0.22);
}

.btn-install {
  position: relative;
  overflow: hidden;
  border: 1px solid var(--accent);
  background: rgba(78, 161, 255, 0.08);
  color: var(--accent-2);
  font-weight: 700;
}

.btn-install:hover {
  background: linear-gradient(135deg, var(--accent), var(--accent-2));
  color: #04101f;
  border-color: transparent;
  box-shadow: 0 10px 26px rgba(78, 161, 255, 0.25);
  transform: translateY(-2px);
}

.btn-install::before {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(120deg, transparent, rgba(255, 255, 255, 0.2), transparent);
  opacity: 0;
  transition: opacity 0.4s ease;
}

.btn-install:hover::before {
  opacity: 1;
}

.refresh-top-btn {
  min-width: 44px;
  min-height: 44px;
  padding: 8px 11px;
  line-height: 1;
}

.music-toggle-btn {
  box-shadow:
    0 10px 28px rgba(0, 0, 0, 0.28),
    0 0 0 1px rgba(124, 196, 255, 0.05);
}

/* =========================
   GRID / CARDS
========================= */

.grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 18px;
}

.library-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 16px;
}

.card,
.topic-card,
.note-box,
.pdf-shell,
.pdf-card {
  background: var(--panel);
  border: 1px solid var(--line-soft);
  border-radius: 22px;
  box-shadow: var(--shadow);
}

.card,
.topic-card {
  padding: 20px;
  transition:
    transform var(--transition-mid),
    border-color var(--transition-mid),
    box-shadow var(--transition-mid),
    background var(--transition-mid);
}

.card:hover,
.topic-card:hover {
  transform: translateY(-4px) scale(1.01);
  border-color: rgba(124, 196, 255, 0.28);
  box-shadow:
    0 22px 50px rgba(0, 0, 0, 0.45),
    0 0 0 1px rgba(124, 196, 255, 0.04);
}

.card-top {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 12px;
}

.card h3,
.topic-card h2,
.pdf-card h3 {
  margin: 0 0 8px;
  font-size: 1.16rem;
  line-height: 1.25;
  letter-spacing: -0.01em;
}

.card p,
.topic-card p,
.pdf-card p {
  margin: 0 0 16px;
  color: var(--muted);
  font-size: 0.97rem;
}

.card-actions,
.actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 18px;
}

.dashboard-section .grid .card h3 {
  margin-top: 0;
}

/* =========================
   PIN BUTTON
========================= */

.pin-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  min-width: 40px;
  height: 40px;
  border-radius: 999px;
  border: 1px solid var(--line-soft);
  background: rgba(255, 255, 255, 0.03);
  color: var(--muted);
  font-size: 1.15rem;
  cursor: pointer;
  box-shadow: var(--shadow-soft);
  transition:
    transform var(--transition-fast),
    border-color var(--transition-fast),
    color var(--transition-fast),
    background var(--transition-fast);
}

.pin-btn:hover {
  border-color: var(--accent);
  color: var(--accent-2);
  transform: translateY(-1px);
}

.pin-btn:active {
  transform: scale(0.96);
}

.pin-btn.pinned {
  color: #ffd54a;
  border-color: rgba(255, 213, 74, 0.35);
  background: rgba(255, 213, 74, 0.08);
}

/* =========================
   CONTROLS
========================= */

.controls-wrap {
  display: flex;
  flex-wrap: wrap;
  align-items: stretch;
  gap: 12px;
}

.search-box,
.filter-box {
  flex: 1 1 260px;
}

.search-box input,
.filter-box select,
.music-select {
  width: 100%;
  min-height: 52px;
  padding: 12px 14px;
  border-radius: 14px;
  border: 1px solid var(--line-soft);
  background: linear-gradient(180deg, rgba(17, 26, 43, 0.96), rgba(12, 18, 31, 0.96));
  color: var(--text);
  font-size: 0.97rem;
  outline: none;
  box-shadow: var(--shadow-soft);
  transition:
    border-color var(--transition-fast),
    box-shadow var(--transition-fast),
    transform var(--transition-fast),
    background var(--transition-fast);
}

.filter-box select {
  appearance: none;
  -webkit-appearance: none;
  -moz-appearance: none;
  padding-right: 44px;
  cursor: pointer;
}

.filter-box select option,
.music-select option {
  background: #0f1728;
  color: #e8eefc;
}

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

.search-box input:focus,
.filter-box select:focus,
.music-select:focus {
  border-color: rgba(124, 196, 255, 0.35);
  box-shadow:
    0 0 0 4px rgba(78, 161, 255, 0.09),
    var(--shadow-soft);
}

#subjectGrid {
  min-height: 120px;
}

#subjectSearch::-webkit-contacts-auto-fill-button,
#subjectSearch::-webkit-credentials-auto-fill-button {
  visibility: hidden;
  pointer-events: none;
  position: absolute;
  right: 0;
}

/* =========================
   VIEWER / NOTE / PDF
========================= */

.note-box {
  padding: 24px;
  background: linear-gradient(180deg, rgba(17, 26, 43, 0.96), rgba(12, 18, 31, 0.96));
}

.note-box h2 {
  margin: 0 0 10px;
  font-size: 1.5rem;
}

.note-box p {
  margin: 0 0 16px;
  color: var(--muted);
}

.viewer-wrap {
  padding: 28px 0 40px;
}

.viewer-topbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 14px;
  margin-bottom: 16px;
}

.viewer-title {
  margin: 0;
  font-size: 1.55rem;
  letter-spacing: -0.02em;
}

.pdf-shell {
  padding: 14px;
  background: linear-gradient(180deg, rgba(17, 26, 43, 0.96), rgba(12, 18, 31, 0.96));
}

.pdf-toolbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 12px;
  margin-bottom: 12px;
  padding-bottom: 12px;
  border-bottom: 1px solid var(--line-soft);
}

.pdf-toolbar-text {
  color: var(--muted);
  font-size: 0.95rem;
}

.pdf-frame {
  width: 100%;
  height: 85vh;
  border: 1px solid var(--line-soft);
  border-radius: 18px;
  background: #0a1322;
}

.helper {
  margin-top: 14px;
  color: var(--muted);
  font-size: 0.95rem;
}

.pdf-card {
  padding: 18px;
  background: linear-gradient(180deg, rgba(17, 26, 43, 0.96), rgba(12, 18, 31, 0.96));
  box-shadow: var(--shadow-soft);
  transition:
    transform var(--transition-mid),
    border-color var(--transition-mid),
    box-shadow var(--transition-mid);
}

.pdf-card:hover {
  transform: translateY(-3px);
  border-color: rgba(124, 196, 255, 0.24);
  box-shadow: 0 16px 36px rgba(0, 0, 0, 0.3);
}

#pdfViewer {
  width: 100%;
  min-height: 70vh;
  padding: 18px;
  overflow: auto;
  border-radius: 18px;
  background: #0a1322;
}

.pdf-page {
  display: block;
  margin: 0 auto 18px;
  max-width: 100%;
  height: auto;
  border-radius: 12px;
  box-shadow: 0 10px 24px rgba(0, 0, 0, 0.3);
  background: #ffffff;
}

.share-row {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 14px;
}

.share-link {
  display: inline-block;
}

.loading {
  color: var(--muted);
  text-align: center;
  padding: 30px 0;
  line-height: 1.7;
}

.topic-share-actions {
  margin-top: 12px;
}

.topic-helper-text {
  margin-top: 16px;
  color: var(--muted);
  font-size: 0.95rem;
}

/* =========================
   FOOTER
========================= */

.footer {
  margin-top: 50px;
  padding: 24px 0 40px;
  border-top: 1px solid var(--line-soft);
  color: var(--muted);
  font-size: 0.94rem;
}

.footer a {
  color: var(--muted);
  transition: color var(--transition-fast);
}

.footer a:hover {
  color: var(--accent-2);
}

/* =========================
   PULL / UPDATE / LOADING
========================= */

.pull-refresh-indicator {
  position: fixed;
  top: 70px;
  left: 50%;
  transform: translateX(-50%);
  z-index: 2000;
  opacity: 0;
  pointer-events: none;
  padding: 8px 14px;
  border: 1px solid var(--line-soft);
  border-radius: 999px;
  background: rgba(17, 26, 43, 0.96);
  color: var(--text);
  box-shadow: var(--shadow-soft);
  font-size: 0.92rem;
  transition: opacity var(--transition-fast), transform var(--transition-fast);
}

.pull-refresh-indicator.show {
  opacity: 1;
  transform: translateX(-50%) translateY(6px);
}

.loading-overlay {
  position: fixed;
  inset: 0;
  z-index: 3000;
  display: none;
  align-items: center;
  justify-content: center;
  background: rgba(9, 16, 28, 0.72);
  backdrop-filter: blur(4px);
  -webkit-backdrop-filter: blur(4px);
}

.loading-overlay.show {
  display: flex;
}

.loading-box {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 12px;
  min-width: 180px;
  padding: 22px 26px;
  border: 1px solid var(--line-soft);
  border-radius: 18px;
  background: linear-gradient(180deg, rgba(17, 26, 43, 0.98), rgba(12, 18, 31, 0.98));
  box-shadow: var(--shadow);
}

.spinner {
  width: 38px;
  height: 38px;
  border: 4px solid rgba(255, 255, 255, 0.14);
  border-top-color: var(--accent-2);
  border-radius: 50%;
  animation: spin 0.9s linear infinite;
}

.loading-text {
  color: var(--text);
  font-size: 0.96rem;
  font-weight: 700;
  transition: all 0.2s ease;
}

.update-toast {
  position: fixed;
  right: 16px;
  bottom: 16px;
  z-index: 3500;
  display: none;
  max-width: min(92vw, 360px);
  padding: 16px;
  border: 1px solid var(--line-soft);
  border-radius: 18px;
  background: linear-gradient(180deg, rgba(17, 26, 43, 0.98), rgba(12, 18, 31, 0.98));
  color: var(--text);
  box-shadow: var(--shadow);
}

.update-toast.show {
  display: block;
  animation: toastUp 0.28s ease;
}

.update-toast h3 {
  margin: 0 0 8px;
  font-size: 1rem;
}

.update-toast p {
  margin: 0 0 12px;
  color: var(--muted);
  font-size: 0.94rem;
  line-height: 1.5;
}

.update-toast-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.quiz-update-banner {
  position: fixed;
  top: 78px;
  left: 50%;
  transform: translateX(-50%);
  z-index: 2600;
  display: none;
  width: min(92vw, 520px);
  padding: 12px 16px;
  border-radius: 16px;
  background: linear-gradient(135deg, #ffb347, #ffcc33);
  color: #04101f;
  box-shadow: 0 10px 24px rgba(0, 0, 0, 0.3);
  font-weight: 700;
  font-size: 0.93rem;
  text-align: center;
  line-height: 1.45;
}

.quiz-update-banner.show {
  display: block;
}

.quiz-update-banner button {
  margin-top: 10px;
  padding: 8px 12px;
  border: none;
  border-radius: 10px;
  background: #04101f;
  color: #fff;
  font-weight: 700;
  cursor: pointer;
}

/* =========================
   SPLASH
========================= */

.app-splash {
  position: fixed;
  inset: 0;
  z-index: 9999;
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
  opacity: 1;
  visibility: visible;
  background:
    radial-gradient(circle at top, rgba(78, 161, 255, 0.16), transparent 30%),
    linear-gradient(180deg, #08101c 0%, #0b1220 100%);
  transition: opacity 0.7s ease, visibility 0.7s ease;
}

.app-splash.hide {
  opacity: 0;
  visibility: hidden;
  pointer-events: none;
}

.app-splash-bg {
  position: absolute;
  inset: 0;
  background:
    radial-gradient(circle at 20% 20%, rgba(124, 196, 255, 0.1), transparent 18%),
    radial-gradient(circle at 80% 25%, rgba(78, 161, 255, 0.08), transparent 20%),
    radial-gradient(circle at 50% 85%, rgba(124, 196, 255, 0.06), transparent 20%);
  animation: splashFloat 6s ease-in-out infinite alternate;
}

.app-splash-content {
  position: relative;
  width: min(90vw, 420px);
  padding: 24px;
  text-align: center;
  animation: splashRise 0.9s ease;
}

.app-splash-logo-wrap {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
  width: 110px;
  height: 110px;
  margin: 0 auto 20px;
}

.app-splash-ring {
  position: absolute;
  inset: 0;
  border-radius: 50%;
  border: 2px solid rgba(124, 196, 255, 0.25);
  box-shadow:
    0 0 0 10px rgba(78, 161, 255, 0.05),
    0 0 40px rgba(78, 161, 255, 0.18);
  animation: ringPulse 2s ease-in-out infinite;
}

.app-splash-logo {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 78px;
  height: 78px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--accent), var(--accent-2));
  color: #04101f;
  font-size: 1.7rem;
  font-weight: 900;
  letter-spacing: 0.5px;
  box-shadow:
    0 10px 30px rgba(78, 161, 255, 0.3),
    inset 0 1px 0 rgba(255, 255, 255, 0.35);
  animation: logoGlow 2.4s ease-in-out infinite;
}

.app-splash-title {
  margin: 0 0 8px;
  font-size: clamp(1.8rem, 5vw, 2.4rem);
  line-height: 1.1;
  letter-spacing: -0.02em;
}

.app-splash-subtitle {
  margin: 0 0 22px;
  color: var(--muted);
  font-size: 1rem;
}

.app-splash-loader {
  width: 100%;
  height: 8px;
  overflow: hidden;
  border: 1px solid rgba(255, 255, 255, 0.06);
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.08);
}

.app-splash-loader-bar {
  width: 0%;
  height: 100%;
  border-radius: 999px;
  background: linear-gradient(90deg, var(--accent), var(--accent-2));
  box-shadow: 0 0 18px rgba(124, 196, 255, 0.35);
  animation: splashLoad 2s ease forwards;
}

/* =========================
   GLOBAL TOAST
========================= */

.toast {
  position: fixed;
  left: 50%;
  bottom: 20px;
  transform: translateX(-50%) translateY(20px);
  z-index: 4000;
  opacity: 0;
  pointer-events: none;
  padding: 12px 18px;
  border: 1px solid var(--line-soft);
  border-radius: 14px;
  background: linear-gradient(180deg, rgba(17, 26, 43, 0.98), rgba(12, 18, 31, 0.98));
  color: var(--text);
  box-shadow: var(--shadow);
  font-weight: 700;
  font-size: 0.92rem;
  transition: all 0.25s ease;
}

.toast.show {
  opacity: 1;
  transform: translateX(-50%) translateY(0);
}

/* =========================
   ONBOARDING
========================= */

.onboarding-overlay {
  position: fixed;
  inset: 0;
  z-index: 5000;
  pointer-events: none;
}

.onboarding-overlay.is-hidden {
  display: none;
}

.onboarding-backdrop {
  position: absolute;
  inset: 0;
  background: rgba(8, 16, 28, 0.75);
  pointer-events: none;
}

.onboarding-spotlight {
  position: absolute;
  border-radius: 14px;
  border: 2px solid rgba(124, 196, 255, 0.6);
  box-shadow:
    0 0 0 2000px rgba(8, 16, 28, 0.7),
    0 0 20px rgba(124, 196, 255, 0.4);
  transition: all 0.25s ease;
  pointer-events: none;
}

.onboarding-card {
  position: absolute;
  z-index: 5002;
  width: min(92vw, 320px);
  padding: 16px;
  border: 1px solid var(--line-soft);
  border-radius: 16px;
  background: linear-gradient(180deg, rgba(17, 26, 43, 0.98), rgba(12, 18, 31, 0.98));
  box-shadow: var(--shadow);
  animation: onboardingFade 0.25s ease;
  pointer-events: auto;
}

.onboarding-step {
  margin-bottom: 4px;
  color: var(--accent-2);
  font-size: 0.8rem;
  font-weight: 700;
}

.onboarding-card h3 {
  margin: 0 0 6px;
  font-size: 1.05rem;
}

.onboarding-card p {
  margin: 0 0 12px;
  color: var(--muted);
  font-size: 0.9rem;
}

.onboarding-actions {
  display: flex;
  justify-content: space-between;
  gap: 10px;
}

.onboarding-arrow {
  position: absolute;
  z-index: 5003;
  color: var(--accent-2);
  font-size: 20px;
  animation: arrowPulse 1s infinite;
}

/* =========================
   AUTH MODAL
========================= */

.auth-modal {
  position: fixed;
  inset: 0;
  z-index: 9999;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 12px;
  background: rgba(9, 16, 28, 0.75);
  backdrop-filter: blur(6px);
  -webkit-backdrop-filter: blur(6px);
  animation: fadeIn 0.25s ease;
}

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

.auth-box {
  width: min(92vw, 360px);
  max-height: min(90vh, 820px);
  overflow-y: auto;
  padding: 24px;
  border: 1px solid var(--line-soft);
  border-radius: 20px;
  background: linear-gradient(180deg, rgba(17, 26, 43, 0.98), rgba(12, 18, 31, 0.98));
  box-shadow:
    var(--shadow),
    0 0 30px rgba(78, 161, 255, 0.15);
  animation: slideUp 0.3s ease;
}

.auth-box h2 {
  margin: 0 0 14px;
  text-align: center;
  color: var(--text);
  font-size: 1.4rem;
}

.auth-box input,
.auth-box textarea {
  width: 100%;
  padding: 12px;
  margin: 10px 0;
  border: 1px solid var(--line-soft);
  border-radius: 12px;
  background: rgba(255, 255, 255, 0.04);
  color: var(--text);
  outline: none;
  transition: 0.2s ease;
}

.auth-box input:focus,
.auth-box textarea:focus {
  border-color: var(--accent);
  box-shadow: 0 0 0 3px var(--accent-ring);
}

.auth-box .btn {
  width: 100%;
  margin-top: 10px;
}

.auth-message-box {
  text-align: center;
}

.auth-message-text {
  margin: 10px 0 18px;
  color: var(--muted);
  line-height: 1.6;
  word-break: break-word;
}

.auth-message-actions {
  display: flex;
  gap: 10px;
  flex-wrap: wrap;
}

.auth-message-actions .btn {
  flex: 1;
}

#authToggleText {
  margin-top: 14px;
  text-align: center;
  color: var(--muted);
  font-size: 0.9rem;
}

#authToggleBtn {
  color: var(--accent-2);
  font-weight: 700;
  cursor: pointer;
}

#authCloseBtn {
  margin-top: 10px;
}

.auth-password-wrap {
  position: relative;
}

.auth-password-wrap input {
  padding-right: 52px;
}

.auth-eye-btn {
  position: absolute;
  top: 50%;
  right: 10px;
  transform: translateY(-50%);
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 38px;
  height: 38px;
  min-width: 38px;
  min-height: 38px;
  border: 1px solid var(--line-soft);
  border-radius: 10px;
  background: rgba(255, 255, 255, 0.03);
  color: var(--muted);
  cursor: pointer;
  transition:
    all 0.25s ease,
    transform 0.15s ease;
}

.auth-eye-btn:hover {
  border-color: var(--accent);
  color: var(--accent-2);
  background: rgba(78, 161, 255, 0.08);
  box-shadow: 0 0 12px rgba(78, 161, 255, 0.25);
}

.auth-eye-btn:active {
  transform: translateY(-50%) scale(0.92);
}

.auth-eye-btn:focus-visible {
  outline: none;
  box-shadow: 0 0 0 3px var(--accent-ring);
}

.auth-eye-btn svg {
  pointer-events: none;
  transition:
    transform 0.2s ease,
    opacity 0.2s ease,
    filter 0.2s ease;
}

.auth-eye-btn:hover svg {
  transform: scale(1.1);
  filter: drop-shadow(0 0 6px rgba(124, 196, 255, 0.35));
}

.auth-forgot {
  margin-top: 8px;
  text-align: right;
  font-size: 13px;
}

.auth-forgot span {
  color: var(--accent);
  cursor: pointer;
}

.auth-forgot span:hover {
  text-decoration: underline;
}

.auth-confirm {
  margin-top: 8px;
}

/* =========================
   PREMIUM PROFILE SECTION
========================= */

.premium-auth-box {
  width: min(720px, calc(100vw - 24px));
  max-width: 720px;
}

.profile-editor-section {
  margin-bottom: 18px;
  padding: 16px;
  border-radius: 18px;
  border: 1px solid rgba(255, 255, 255, 0.08);
  background:
    radial-gradient(circle at top right, rgba(78, 161, 255, 0.1), transparent 32%),
    linear-gradient(180deg, rgba(15, 23, 38, 0.96), rgba(10, 18, 32, 0.95));
  box-shadow: 0 14px 30px rgba(0, 0, 0, 0.24);
}

.profile-editor-header {
  display: grid;
  grid-template-columns: 86px 1fr;
  align-items: center;
  gap: 14px;
  margin-bottom: 16px;
}

.profile-avatar-preview-wrap {
  width: 86px;
  height: 86px;
  border-radius: 50%;
  overflow: hidden;
  border: 2px solid rgba(78, 161, 255, 0.34);
  background: rgba(255, 255, 255, 0.05);
  box-shadow: 0 10px 22px rgba(0, 0, 0, 0.22);
}

.profile-avatar-preview {
  width: 100%;
  height: 100%;
  display: block;
  object-fit: cover;
}

.profile-editor-meta {
  min-width: 0;
}

.profile-editor-badge {
  display: inline-flex;
  align-items: center;
  min-height: 28px;
  padding: 6px 10px;
  margin-bottom: 8px;
  border-radius: 999px;
  background: rgba(78, 161, 255, 0.1);
  border: 1px solid rgba(124, 196, 255, 0.16);
  color: #cfe6ff;
  font-size: 12px;
  font-weight: 700;
}

.profile-editor-heading {
  margin-bottom: 4px;
  color: #eaf1ff;
  font-size: 20px;
  font-weight: 800;
  line-height: 1.2;
}

.profile-editor-subtext {
  color: #a8b3cf;
  font-size: 14px;
  line-height: 1.6;
}

.profile-editor-fields {
  display: grid;
  grid-template-columns: 1fr;
  gap: 10px;
  margin-bottom: 16px;
}

.profile-input,
.profile-bio-input {
  width: 100%;
  box-sizing: border-box;
  padding: 12px 14px;
  border-radius: 14px;
  border: 1px solid rgba(255, 255, 255, 0.08);
  background: #0d1625;
  color: #e8eefc;
  outline: none;
  transition: border-color 0.18s ease, box-shadow 0.18s ease, background 0.18s ease;
}

.profile-input:focus,
.profile-bio-input:focus {
  border-color: rgba(78, 161, 255, 0.55);
  box-shadow: 0 0 0 3px rgba(78, 161, 255, 0.14);
  background: #101b2d;
}

.profile-bio-input {
  resize: vertical;
  min-height: 96px;
}

.avatar-section-head {
  display: flex;
  align-items: end;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 12px;
  margin-bottom: 10px;
}

.avatar-section-title {
  color: #d9e8ff;
  font-size: 14px;
  font-weight: 800;
}

.avatar-section-subtitle {
  color: #8fa2c4;
  font-size: 12px;
}

.preset-avatar-grid {
  display: grid;
  grid-template-columns: repeat(5, minmax(0, 1fr));
  gap: 12px;
  max-height: 290px;
  overflow: auto;
  padding: 6px;
  border-radius: 16px;
  background: rgba(255, 255, 255, 0.03);
  border: 1px solid rgba(255, 255, 255, 0.06);
}

.preset-avatar-grid button[data-avatar-id] {
  width: 100%;
  aspect-ratio: 1 / 1;
  padding: 0;
  overflow: hidden;
  border-radius: 50%;
  border: 2px solid rgba(255, 255, 255, 0.08);
  background: rgba(255, 255, 255, 0.04);
  cursor: pointer;
  box-shadow: 0 8px 18px rgba(0, 0, 0, 0.18);
  transition:
    transform 0.18s ease,
    box-shadow 0.18s ease,
    border-color 0.18s ease,
    filter 0.18s ease;
}

.preset-avatar-grid button[data-avatar-id]:hover {
  transform: translateY(-2px) scale(1.04);
  border-color: rgba(124, 196, 255, 0.34);
  box-shadow: 0 12px 24px rgba(0, 0, 0, 0.24), 0 0 0 1px rgba(78, 161, 255, 0.06);
}

.preset-avatar-grid button[data-avatar-id] img {
  width: 100%;
  height: 100%;
  display: block;
  object-fit: cover;
}

/* =========================
   SUBJECT CHOOSER MODAL
========================= */

.subject-modal {
  position: fixed;
  inset: 0;
  z-index: 10000;
}

.subject-modal.hidden {
  display: none !important;
}

.subject-modal-backdrop {
  position: absolute;
  inset: 0;
  background: rgba(7, 13, 24, 0.78);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
}

.subject-modal-box {
  position: relative;
  width: min(92vw, 460px);
  margin: 70px auto 0;
  padding: 22px;
  border-radius: 24px;
  background: linear-gradient(180deg, rgba(14, 22, 38, 0.98), rgba(10, 16, 29, 0.98));
  border: 1px solid rgba(124, 196, 255, 0.16);
  box-shadow:
    0 28px 70px rgba(0, 0, 0, 0.5),
    0 0 0 1px rgba(78, 161, 255, 0.05),
    0 0 40px rgba(78, 161, 255, 0.08);
  animation: subjectModalIn 0.24s ease;
}

.subject-modal-top {
  text-align: center;
  margin-bottom: 18px;
}

.subject-modal-badge {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 6px 12px;
  margin-bottom: 12px;
  border-radius: 999px;
  background: rgba(78, 161, 255, 0.1);
  border: 1px solid rgba(124, 196, 255, 0.2);
  color: var(--accent-2);
  font-size: 0.82rem;
  font-weight: 700;
}

.subject-modal-top h2 {
  margin: 0 0 8px;
  font-size: 2rem;
  line-height: 1.1;
  letter-spacing: -0.02em;
}

.subject-modal-top p {
  margin: 0;
  color: var(--muted);
  font-size: 0.98rem;
}

.subject-modal-list {
  display: grid;
  gap: 12px;
}

.subject-card-btn {
  width: 100%;
  padding: 16px;
  display: flex;
  align-items: center;
  gap: 14px;
  border: 1px solid rgba(124, 196, 255, 0.14);
  border-radius: 18px;
  background: linear-gradient(180deg, rgba(20, 31, 52, 0.95), rgba(15, 24, 42, 0.95));
  color: var(--text);
  cursor: pointer;
  transition:
    transform 0.18s ease,
    border-color 0.18s ease,
    box-shadow 0.18s ease,
    background 0.18s ease;
}

.subject-card-btn:hover {
  transform: translateY(-2px);
  border-color: rgba(124, 196, 255, 0.3);
  box-shadow:
    0 14px 28px rgba(0, 0, 0, 0.28),
    0 0 0 1px rgba(124, 196, 255, 0.04);
}

.subject-card-btn.is-physics {
  border-color: transparent;
  background: linear-gradient(135deg, rgba(78, 161, 255, 0.96), rgba(124, 196, 255, 0.96));
  color: #04101f;
}

.subject-card-btn.is-physics .subject-card-text small {
  color: rgba(4, 16, 31, 0.78);
}

.subject-card-icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 46px;
  height: 46px;
  min-width: 46px;
  border-radius: 14px;
  background: rgba(255, 255, 255, 0.08);
  font-size: 1.2rem;
}

.subject-card-btn.is-physics .subject-card-icon {
  background: rgba(255, 255, 255, 0.22);
}

.subject-card-text {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  text-align: left;
}

.subject-card-text strong {
  font-size: 1.05rem;
  line-height: 1.2;
}

.subject-card-text small {
  margin-top: 4px;
  color: var(--muted);
  font-size: 0.84rem;
  line-height: 1.45;
}

.subject-modal-footer {
  display: flex;
  justify-content: center;
  margin-top: 16px;
}

.subject-cancel-btn {
  min-width: 130px;
  width: auto;
  border-color: rgba(255, 255, 255, 0.08);
  background: rgba(255, 255, 255, 0.03);
}

/* =========================
   QUIZ UI
========================= */

.quiz-progress-strip {
  margin-top: 10px;
}

.quiz-progress-label-row {
  display: flex;
  justify-content: space-between;
  margin-bottom: 4px;
  color: var(--muted);
  font-size: 0.85rem;
}

.quiz-progress-bar {
  width: 100%;
  height: 8px;
  overflow: hidden;
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.08);
}

.quiz-progress-fill {
  width: 0%;
  height: 100%;
  background: linear-gradient(90deg, var(--accent), var(--accent-2));
  transition: width 0.3s ease;
}

.question-palette {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(40px, 1fr));
  gap: 8px;
  margin-top: 16px;
}

.palette-btn {
  width: 100%;
  height: 40px;
  border: 1px solid var(--line-soft);
  border-radius: 10px;
  background: rgba(255, 255, 255, 0.03);
  color: var(--text);
  font-weight: 700;
  cursor: pointer;
  transition: 0.2s ease;
}

.palette-btn:hover {
  border-color: var(--accent);
}

.palette-btn.is-current {
  border-color: transparent;
  background: linear-gradient(135deg, var(--accent), var(--accent-2));
  color: #04101f;
}

.palette-btn.is-answered {
  border-color: var(--success);
}

.palette-btn.is-flagged {
  box-shadow: inset 0 0 0 2px var(--warning);
}

.palette-btn.is-unanswered {
  opacity: 0.65;
}

.answer-btn.correct-answer {
  background: var(--success) !important;
  color: #fff !important;
  border-color: transparent !important;
}

.answer-btn.wrong-answer {
  background: var(--danger) !important;
  color: #fff !important;
  border-color: transparent !important;
}

.answer-btn.review-dim {
  opacity: 0.5;
}

.subtopic-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 12px;
}

.meta-pill {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 32px;
  padding: 6px 10px;
  border: 1px solid var(--line-soft);
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.04);
  color: var(--muted);
  font-size: 0.84rem;
  font-weight: 700;
}

/* =========================
   MUSIC PLAYER
========================= */

.music-player-wrap {
  position: fixed;
  right: 20px;
  bottom: 20px;
  z-index: 2600;
  display: flex;
  flex-direction: column;
  align-items: flex-end;
}

.music-panel {
  display: none;
  width: 290px;
  margin-top: 10px;
  padding: 14px;
  border: 1px solid var(--line-soft);
  border-radius: 18px;
  background: linear-gradient(180deg, rgba(17, 26, 43, 0.98), rgba(12, 18, 31, 0.98));
  box-shadow: var(--shadow);
}

.music-panel.show {
  display: block;
  animation: toastUp 0.22s ease;
}

.music-panel-title {
  margin-bottom: 10px;
  color: var(--accent-2);
  font-weight: 800;
  letter-spacing: 0.2px;
}

.music-label {
  display: block;
  margin-bottom: 8px;
  color: var(--muted);
  font-size: 0.95rem;
}

.music-controls {
  display: flex;
  gap: 10px;
  margin-bottom: 12px;
}

.music-controls .btn {
  flex: 1;
}

.volume-slider {
  width: 100%;
  margin-top: 4px;
  accent-color: var(--accent);
}

.music-track-label {
  margin-top: 10px;
  color: var(--muted);
  font-size: 0.92rem;
  line-height: 1.5;
  text-align: left;
}

/* =========================
   MOBILE VIEWER ACTION SIZE FIX
========================= */

@media (max-width: 768px) {
  #viewerActions.actions {
    display: flex;
    flex-direction: row !important;
    flex-wrap: wrap;
    gap: 6px;
    width: 100%;
    margin-top: 12px;
  }

  #viewerActions .btn,
  .zoom-controls .btn {
    height: 36px !important;
    min-height: 36px !important;
    padding: 0 10px !important;
    font-size: 0.78rem !important;
    border-radius: 10px !important;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    line-height: 1;
  }

  #viewerActions .btn {
    flex: 1 1 calc(33.333% - 6px);
    width: auto !important;
    min-width: 0 !important;
  }

  #viewerActions .btn.btn-primary {
    font-weight: 800;
  }
}

@media (max-width: 600px) {
  #viewerActions.actions {
    flex-direction: row !important;
  }

  #viewerActions .btn {
    width: auto !important;
  }
}

/* =========================
   RESPONSIVE
========================= */

@media (min-width: 769px) {
  .profile-editor-fields {
    grid-template-columns: 1fr;
  }

  .premium-auth-box {
    padding: 22px;
  }
}

@media (max-width: 900px) {
  .grid {
    grid-template-columns: 1fr;
  }

  .nav {
    flex-direction: column;
    align-items: flex-start;
  }

  .page-title h1 {
    font-size: 2rem;
  }

  .viewer-title {
    font-size: 1.35rem;
  }

  .pdf-frame {
    height: 72vh;
  }

  .topbar-right {
    width: 100%;
    justify-content: space-between;
  }

  .user-email-display {
    max-width: 180px;
  }
}

@media (max-width: 768px) {
  .library-grid {
    grid-template-columns: 1fr;
  }

  #pdfViewer {
    min-height: 60vh;
    padding: 12px;
  }

  .pdf-card {
    padding: 14px;
    border-radius: 18px;
  }

  .music-player-wrap {
    right: 14px;
    bottom: 14px;
  }

  .music-panel {
    width: min(88vw, 300px);
  }

  .quiz-update-banner {
    top: 72px;
    width: min(94vw, 520px);
    font-size: 0.9rem;
  }

  .premium-auth-box {
    width: min(100vw - 16px, 560px);
    padding: 14px;
    border-radius: 18px;
  }

  .profile-editor-section {
    padding: 12px;
    border-radius: 16px;
  }

  .profile-editor-header {
    grid-template-columns: 70px 1fr;
    gap: 10px;
    align-items: center;
  }

  .profile-avatar-preview-wrap {
    width: 70px;
    height: 70px;
  }

  .profile-editor-heading {
    font-size: 17px;
  }

  .profile-editor-subtext {
    font-size: 13px;
  }

  .preset-avatar-grid {
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 10px;
    max-height: 250px;
  }

  .profile-input,
  .profile-bio-input {
    padding: 11px 12px;
    font-size: 14px;
  }
}

@media (max-width: 600px) {
  .container {
    width: min(100% - 20px, 1120px);
  }

  .hero {
    padding: 56px 0 34px;
  }

  .section {
    padding: 24px 0 42px;
  }

  .card,
  .topic-card,
  .note-box,
  .pdf-shell {
    padding: 18px;
    border-radius: 18px;
  }

  .btn {
    width: 100%;
  }

  .actions {
    flex-direction: column;
  }

  .card-top {
    align-items: center;
  }

  .search-box,
  .filter-box {
    flex: 1 1 100%;
  }

  .pdf-frame {
    height: 65vh;
  }

  .update-toast {
    left: 12px;
    right: 12px;
    bottom: 12px;
    max-width: none;
  }

  .app-splash-content {
    width: min(92vw, 380px);
  }

  .music-controls {
    flex-direction: column;
  }

  .quiz-update-banner {
    top: 68px;
    padding: 10px 12px;
  }

  .question-palette {
    grid-template-columns: repeat(auto-fill, minmax(36px, 1fr));
  }

  .palette-btn {
    height: 36px;
    font-size: 0.88rem;
  }

  .hero-actions {
    flex-direction: column;
    align-items: stretch;
  }

  .hero-action-btn {
    width: 100%;
    min-width: 0;
  }

  .subject-modal-box {
    width: min(94vw, 460px);
    margin-top: 34px;
    padding: 18px;
    border-radius: 20px;
  }

  .subject-modal-top h2 {
    font-size: 1.7rem;
  }

  .subject-card-btn {
    padding: 14px;
    border-radius: 16px;
  }

  .subject-card-icon {
    width: 42px;
    height: 42px;
    min-width: 42px;
  }

  .auth-box {
    padding: 18px;
  }

  .topbar-right {
    gap: 8px;
  }

  .user-email-display {
    order: 5;
    width: 100%;
    max-width: none;
    white-space: normal;
    overflow: visible;
    text-overflow: initial;
  }
}

@media (max-width: 480px) {
  .profile-editor-header {
    grid-template-columns: 1fr;
    text-align: center;
  }

  .profile-avatar-preview-wrap {
    margin: 0 auto;
  }

  .preset-avatar-grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 9px;
  }

  .avatar-section-head {
    align-items: start;
  }
}

/* =========================
   ANIMATIONS
========================= */

@keyframes spin {
  to {
    transform: rotate(360deg);
  }
}

@keyframes splashLoad {
  0% {
    width: 0%;
  }
  100% {
    width: 100%;
  }
}

@keyframes splashRise {
  0% {
    transform: translateY(18px);
    opacity: 0;
  }
  100% {
    transform: translateY(0);
    opacity: 1;
  }
}

@keyframes logoGlow {
  0%,
  100% {
    transform: scale(1);
    box-shadow:
      0 10px 30px rgba(78, 161, 255, 0.3),
      inset 0 1px 0 rgba(255, 255, 255, 0.35);
  }
  50% {
    transform: scale(1.05);
    box-shadow:
      0 14px 36px rgba(78, 161, 255, 0.42),
      inset 0 1px 0 rgba(255, 255, 255, 0.35);
  }
}

@keyframes ringPulse {
  0%,
  100% {
    transform: scale(1);
    opacity: 0.9;
  }
  50% {
    transform: scale(1.08);
    opacity: 0.55;
  }
}

@keyframes splashFloat {
  0% {
    transform: scale(1) translateY(0);
  }
  100% {
    transform: scale(1.04) translateY(-8px);
  }
}

@keyframes pageFadeIn {
  0% {
    opacity: 0;
    transform: translateY(12px);
  }
  100% {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes toastUp {
  0% {
    opacity: 0;
    transform: translateY(10px);
  }
  100% {
    opacity: 1;
    transform: translateY(0);
  }
}

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

@keyframes arrowPulse {
  0% {
    transform: translateX(0);
    opacity: 0.7;
  }
  50% {
    transform: translateX(6px);
    opacity: 1;
  }
  100% {
    transform: translateX(0);
    opacity: 0.7;
  }
}

@keyframes subjectModalIn {
  from {
    opacity: 0;
    transform: translateY(14px) scale(0.98);
  }
  to {
    opacity: 1;
    transform: translateY(0) scale(1);
  }
}

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

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

/* =========================
   MOBILE TOP BAR FIX
========================= */
@media (max-width: 768px) {
  .site-header .nav {
    flex-direction: row;
    align-items: center;
    justify-content: space-between;
    gap: 10px;
    padding: 12px 0;
  }

  .brand {
    font-size: 1.05rem;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
    max-width: 46vw;
  }

  .topbar-right {
    display: flex;
    align-items: center;
    justify-content: flex-end;
    gap: 8px;
    flex-wrap: nowrap;
    min-width: 0;
  }

  .nav-links {
    display: none;
  }

  .user-email-display {
    display: none !important;
  }

  .top-profile-avatar {
    width: 34px;
    height: 34px;
    min-width: 34px;
  }

  #loginBtn {
    min-width: 44px;
    width: 44px;
    height: 40px;
    min-height: 40px;
    padding: 0;
    font-size: 1rem;
  }

  #refreshBtn {
    min-width: 40px;
    width: 40px;
    height: 40px;
    min-height: 40px;
    padding: 0;
  }
}