/* ═══════════════════════════════════════════════════════════
   QUIZSTACK — style.css
   ═══════════════════════════════════════════════════════════ */

/* ── Google Font ─────────────────────────────────────────── */
@import url('https://fonts.googleapis.com/css2?family=DM+Sans:wght@400;500;600;700;800&family=JetBrains+Mono:wght@500;700&display=swap');

/* ── CSS Variables ───────────────────────────────────────── */
:root {
  --blue:       #2563eb;
  --blue-dark:  #1d4ed8;
  --blue-xd:    #1e40af;
  --blue-light: #eff6ff;
  --blue-ring:  rgba(37,99,235,0.12);
  --green:      #059669;
  --green-bg:   #ecfdf5;
  --green-bdr:  #a7f3d0;
  --red:        #dc2626;
  --red-bg:     #fef2f2;
  --amber:      #d97706;
  --gray-50:    #f9fafb;
  --gray-100:   #f3f4f6;
  --gray-200:   #e5e7eb;
  --gray-300:   #d1d5db;
  --gray-400:   #9ca3af;
  --gray-500:   #6b7280;
  --gray-700:   #374151;
  --gray-900:   #111827;
  --font:       'DM Sans', -apple-system, BlinkMacSystemFont, sans-serif;
  --mono:       'JetBrains Mono', 'Fira Code', monospace;
  --radius-sm:  8px;
  --radius:     12px;
  --radius-lg:  16px;
  --shadow-sm:  0 1px 3px rgba(0,0,0,0.06), 0 1px 2px rgba(0,0,0,0.04);
  --shadow:     0 4px 16px rgba(0,0,0,0.07);
  --transition: 0.18s cubic-bezier(0.4,0,0.2,1);
}

/* ── Reset ───────────────────────────────────────────────── */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
body {
  font-family: var(--font);
  background: #f0f2f5;
  min-height: 100vh;
  color: var(--gray-900);
  -webkit-text-size-adjust: 100%;
  line-height: 1.5;
}

/* ── Top Bar ─────────────────────────────────────────────── */
.topbar {
  background: #fff;
  border-bottom: 1px solid var(--gray-200);
  padding: 0 20px;
  height: 54px;
  display: flex;
  align-items: center;
  gap: 12px;
  position: sticky;
  top: 0;
  z-index: 200;
  box-shadow: var(--shadow-sm);
}
.topbar-logos { display: flex; align-items: center; gap: 10px; flex-shrink: 0; }
.topbar-divider { width: 1px; height: 22px; background: var(--gray-200); flex-shrink: 0; }
.topbar-title {
  font-size: 0.72rem; font-weight: 700; color: var(--gray-500);
  letter-spacing: 0.5px; text-transform: uppercase;
  white-space: nowrap; overflow: hidden; text-overflow: ellipsis;
}
.topbar-right { margin-left: auto; flex-shrink: 0; display: flex; align-items: center; gap: 10px; }

.badge-live {
  display: flex; align-items: center; gap: 5px;
  font-size: 0.68rem; font-weight: 700; color: var(--green);
  background: var(--green-bg); border: 1px solid var(--green-bdr);
  padding: 3px 9px; border-radius: 20px; white-space: nowrap;
}
.badge-live-dot { width: 6px; height: 6px; background: #10b981; border-radius: 50%; animation: blink 2s infinite; flex-shrink: 0; }
@keyframes blink { 0%,100%{opacity:1} 50%{opacity:0.3} }

/* Topbar user */
.topbar-user { display: none; align-items: center; gap: 8px; font-size: 0.75rem; color: var(--gray-700); font-weight: 600; }
.topbar-user.visible { display: flex; }
.topbar-user-avatar {
  width: 30px; height: 30px; border-radius: 50%;
  background: linear-gradient(135deg, #dbeafe, var(--blue));
  display: flex; align-items: center; justify-content: center;
  font-size: 0.65rem; font-weight: 800; color: #fff;
  flex-shrink: 0; overflow: hidden; cursor: pointer;
  border: 2px solid var(--gray-200); transition: var(--transition);
}
.topbar-user-avatar:hover { border-color: var(--blue); }
.topbar-user-avatar img { width: 100%; height: 100%; object-fit: cover; border-radius: 50%; }
.topbar-signout {
  font-size: 0.68rem; color: var(--gray-400); cursor: pointer;
  background: none; border: none; font-family: inherit;
  text-decoration: underline; padding: 0; transition: color 0.2s;
}
.topbar-signout:hover { color: var(--red); }

/* ── Page Layout ─────────────────────────────────────────── */
.page-wrap {
  max-width: 1160px; margin: 0 auto;
  padding: 24px 16px 60px;
  display: grid;
  grid-template-columns: 1fr 360px;
  gap: 20px;
  align-items: start;
}

/* ── Card ────────────────────────────────────────────────── */
.card {
  background: #fff; border-radius: var(--radius-lg);
  border: 1px solid var(--gray-200);
  box-shadow: var(--shadow-sm);
  overflow: hidden;
}
.main-col .card { padding: 32px 36px 36px; }

/* ══ AUTH CARD ══════════════════════════════════════════════ */
.auth-header {
  text-align: center; margin-bottom: 28px;
  padding-bottom: 22px; border-bottom: 1px solid var(--gray-100);
}
.auth-logos { display: flex; align-items: center; justify-content: center; gap: 12px; margin-bottom: 16px; }
.auth-brand-sep { width: 1px; height: 28px; background: var(--gray-200); }
.auth-title { font-size: 1.5rem; font-weight: 800; color: var(--gray-900); letter-spacing: -0.5px; }
.auth-sub   { font-size: 0.8rem; color: var(--gray-500); margin-top: 4px; }

.auth-tabs {
  display: flex; background: var(--gray-100); border-radius: 10px;
  padding: 4px; gap: 4px; margin-bottom: 20px;
}
.auth-tab {
  flex: 1; padding: 9px; text-align: center;
  font-size: 0.85rem; font-weight: 600; color: var(--gray-500);
  border-radius: 7px; cursor: pointer; border: none;
  background: transparent; font-family: inherit; transition: all 0.2s;
  -webkit-tap-highlight-color: transparent;
}
.auth-tab.active { background: #fff; color: var(--blue); box-shadow: 0 1px 4px rgba(0,0,0,0.1); }

/* Google btn */
.btn-google {
  width: 100%; padding: 11px; margin-bottom: 14px;
  background: #fff; border: 1.5px solid var(--gray-200);
  border-radius: var(--radius-sm); cursor: pointer;
  display: flex; align-items: center; justify-content: center; gap: 10px;
  font-size: 0.88rem; font-weight: 600; color: var(--gray-700);
  font-family: inherit; transition: all 0.2s;
  -webkit-tap-highlight-color: transparent;
}
.btn-google:hover { border-color: #4285F4; background: #f8faff; box-shadow: 0 2px 8px rgba(66,133,244,0.15); }
.btn-google svg { width: 18px; height: 18px; flex-shrink: 0; }

.auth-divider {
  text-align: center; margin: 14px 0;
  font-size: 0.72rem; color: var(--gray-400); position: relative;
}
.auth-divider::before, .auth-divider::after {
  content: ''; position: absolute; top: 50%; width: 44%;
  height: 1px; background: var(--gray-200);
}
.auth-divider::before { left: 0; }
.auth-divider::after  { right: 0; }

.auth-form-title {
  font-size: 0.68rem; font-weight: 700; color: var(--gray-400);
  letter-spacing: 1px; text-transform: uppercase; margin-bottom: 16px;
}

/* ── Form ────────────────────────────────────────────────── */
.form-group { margin-bottom: 14px; }
.form-group label { display: block; font-size: 0.77rem; font-weight: 600; color: var(--gray-700); margin-bottom: 5px; }
.form-input {
  width: 100%; padding: 11px 14px;
  border: 1.5px solid var(--gray-200); border-radius: 10px;
  font-size: 1rem; color: var(--gray-900); background: #fff;
  outline: none; transition: border-color 0.2s, box-shadow 0.2s;
  font-family: inherit; -webkit-appearance: none;
}
.form-input::placeholder { color: var(--gray-300); }
.form-input:focus { border-color: var(--blue); box-shadow: 0 0 0 3px var(--blue-ring); }
.form-input.err { border-color: var(--red); box-shadow: 0 0 0 3px rgba(239,68,68,0.08); }
.form-input[readonly] { background: var(--gray-50); color: var(--gray-500); cursor: not-allowed; }

.auth-msg {
  font-size: 0.76rem; min-height: 18px; margin-bottom: 10px;
  font-weight: 500; padding: 0 2px;
  display: flex; align-items: center; gap: 5px;
}
.auth-msg.error   { color: var(--red); }
.auth-msg.success { color: var(--green); }
.auth-msg.info    { color: var(--blue); }

.btn-primary {
  width: 100%; padding: 13px;
  background: var(--blue); color: #fff;
  font-size: 0.95rem; font-weight: 700;
  border: none; border-radius: 10px; cursor: pointer;
  transition: background 0.2s, transform 0.15s, box-shadow 0.2s;
  font-family: inherit; -webkit-tap-highlight-color: transparent;
  touch-action: manipulation;
  display: flex; align-items: center; justify-content: center; gap: 8px;
}
.btn-primary:hover  { background: var(--blue-dark); box-shadow: 0 4px 14px rgba(37,99,235,0.3); transform: translateY(-1px); }
.btn-primary:active { transform: translateY(0); background: var(--blue-xd); }
.btn-primary:disabled { background: #93c5fd; cursor: not-allowed; transform: none; box-shadow: none; }

.btn-spinner {
  width: 16px; height: 16px;
  border: 2px solid rgba(255,255,255,0.4); border-top-color: #fff;
  border-radius: 50%; animation: spin 0.6s linear infinite; display: none;
}
.btn-spinner.show { display: block; }

.otp-info {
  background: #eff6ff; border: 1px solid #bfdbfe;
  border-radius: var(--radius-sm); padding: 12px 14px;
  font-size: 0.78rem; color: #1d4ed8; margin-bottom: 16px; line-height: 1.5;
}
.otp-info strong { display: block; margin-bottom: 2px; }

.resend-link { text-align: center; font-size: 0.72rem; color: var(--gray-500); margin-top: 12px; }
.resend-link button {
  background: none; border: none; color: var(--blue);
  font-size: inherit; cursor: pointer; font-family: inherit;
  text-decoration: underline; padding: 0;
}
.form-note { text-align: center; font-size: 0.7rem; color: var(--gray-400); margin-top: 10px; }

/* ── Registration View ───────────────────────────────────── */
.brand-row {
  display: flex; align-items: center; gap: 16px;
  margin-bottom: 24px; padding-bottom: 20px;
  border-bottom: 1px solid var(--gray-100); flex-wrap: wrap;
}
.brand-logos-row { display: flex; align-items: center; gap: 10px; flex-shrink: 0; }
.brand-sep { width: 1px; height: 30px; background: var(--gray-200); }
.brand-info h1 { font-size: 1.4rem; font-weight: 800; color: var(--gray-900); letter-spacing: -0.3px; line-height: 1; }
.brand-info p  { font-size: 0.8rem; color: var(--gray-500); margin-top: 3px; }

.stats-row { display: flex; gap: 10px; margin-bottom: 26px; flex-wrap: wrap; }
.stat-chip {
  display: flex; align-items: center; gap: 6px;
  padding: 6px 13px; background: var(--gray-50);
  border: 1px solid var(--gray-200); border-radius: var(--radius-sm);
  font-size: 0.76rem; font-weight: 600; color: var(--gray-700); white-space: nowrap;
}
.dot { width: 8px; height: 8px; border-radius: 50%; flex-shrink: 0; }
.dot-blue   { background: #3b82f6; }
.dot-orange { background: #f97316; }
.dot-green  { background: #10b981; }

.form-title { font-size: 0.68rem; font-weight: 700; color: var(--gray-400); letter-spacing: 1px; text-transform: uppercase; margin-bottom: 14px; }

.email-hint { font-size: 0.7rem; margin-top: 5px; min-height: 16px; font-weight: 500; display: flex; align-items: center; gap: 4px; line-height: 1.4; }
.email-hint.ok    { color: var(--green); }
.email-hint.taken { color: var(--red); }
.email-hint.check { color: var(--amber); }

.cognito-verified-badge {
  display: inline-flex; align-items: center; gap: 5px;
  font-size: 0.7rem; font-weight: 600; color: var(--green);
  background: var(--green-bg); border: 1px solid var(--green-bdr);
  padding: 2px 8px; border-radius: 20px; margin-top: 5px;
}

.btn-start {
  width: 100%; padding: 14px; margin-top: 8px;
  background: var(--blue); color: #fff; font-size: 1rem; font-weight: 700;
  border: none; border-radius: 10px; cursor: pointer;
  transition: background 0.2s, transform 0.15s, box-shadow 0.2s;
  font-family: inherit; -webkit-tap-highlight-color: transparent; touch-action: manipulation;
}
.btn-start:hover  { background: var(--blue-dark); box-shadow: 0 4px 14px rgba(37,99,235,0.3); transform: translateY(-1px); }
.btn-start:active { transform: translateY(0); background: var(--blue-xd); }
.btn-start:disabled { background: #93c5fd; cursor: not-allowed; transform: none; box-shadow: none; }

/* ── Profile Photo Upload ─────────────────────────────────── */
.profile-photo-wrap {
  display: flex; align-items: center; gap: 16px; margin-bottom: 20px;
  padding: 14px; background: var(--gray-50); border-radius: var(--radius); border: 1px solid var(--gray-200);
}
.profile-photo-preview {
  width: 64px; height: 64px; border-radius: 50%;
  background: linear-gradient(135deg, #dbeafe, var(--blue));
  display: flex; align-items: center; justify-content: center;
  font-size: 1.3rem; font-weight: 800; color: #fff;
  flex-shrink: 0; overflow: hidden; border: 2px solid var(--gray-200);
}
.profile-photo-preview img { width: 100%; height: 100%; object-fit: cover; border-radius: 50%; }
.profile-photo-info { flex: 1; }
.profile-photo-info p { font-size: 0.8rem; font-weight: 600; color: var(--gray-700); margin-bottom: 4px; }
.profile-photo-info span { font-size: 0.7rem; color: var(--gray-400); }
.btn-upload {
  padding: 7px 14px; background: #fff; border: 1.5px solid var(--gray-200);
  border-radius: var(--radius-sm); font-size: 0.78rem; font-weight: 600;
  color: var(--gray-700); cursor: pointer; font-family: inherit; transition: all 0.2s;
}
.btn-upload:hover { border-color: var(--blue); color: var(--blue); }

/* ── Edit Profile Drawer ──────────────────────────────────── */
.drawer-overlay {
  position: fixed; inset: 0; background: rgba(0,0,0,0.4); z-index: 300;
  display: none; align-items: center; justify-content: center;
  animation: fadeIn 0.2s ease;
}
.drawer-overlay.open { display: flex; }
@keyframes fadeIn { from{opacity:0} to{opacity:1} }
.drawer {
  background: #fff; border-radius: var(--radius-lg); padding: 28px 28px 24px;
  width: 90%; max-width: 440px; max-height: 90vh; overflow-y: auto;
  box-shadow: 0 20px 60px rgba(0,0,0,0.2);
  animation: slideUp 0.3s cubic-bezier(0.34,1.56,0.64,1);
}
@keyframes slideUp { from{transform:translateY(30px);opacity:0} to{transform:translateY(0);opacity:1} }
.drawer-header { display: flex; align-items: center; justify-content: space-between; margin-bottom: 20px; }
.drawer-title { font-size: 1.1rem; font-weight: 800; color: var(--gray-900); }
.drawer-close {
  width: 32px; height: 32px; border-radius: 8px; border: 1px solid var(--gray-200);
  background: #fff; cursor: pointer; display: flex; align-items: center; justify-content: center;
  font-size: 1rem; color: var(--gray-500); transition: all 0.2s;
}
.drawer-close:hover { background: var(--gray-100); color: var(--gray-900); }

/* ── Quiz ────────────────────────────────────────────────── */
#quiz-view .card { padding: 28px 32px 36px; }

/* Timer */
.quiz-timer-wrap {
  display: flex; align-items: center; gap: 8px;
  background: var(--gray-50); border: 1px solid var(--gray-200);
  border-radius: 10px; padding: 8px 14px; margin-bottom: 16px;
  justify-content: space-between;
}
.timer-label { font-size: 0.7rem; font-weight: 700; color: var(--gray-400); letter-spacing: 1px; text-transform: uppercase; }
.timer-display {
  font-family: var(--mono); font-size: 1.3rem; font-weight: 700; color: var(--blue);
  letter-spacing: 2px; transition: color 0.3s;
}
.timer-display.warning { color: var(--amber); }
.timer-display.danger  { color: var(--red); animation: pulse 1s infinite; }
@keyframes pulse { 0%,100%{opacity:1} 50%{opacity:0.6} }
.timer-bar-wrap { height: 4px; background: var(--gray-200); border-radius: 99px; overflow: hidden; margin-top: 6px; }
.timer-bar { height: 100%; background: var(--blue); border-radius: 99px; transition: width 1s linear, background 0.3s; }
.timer-bar.warning { background: var(--amber); }
.timer-bar.danger  { background: var(--red); }

/* Force quit btn */
.btn-force-quit {
  padding: 7px 14px; background: transparent;
  border: 1.5px solid #fca5a5; border-radius: var(--radius-sm);
  font-size: 0.76rem; font-weight: 700; color: var(--red);
  cursor: pointer; font-family: inherit; transition: all 0.2s;
  -webkit-tap-highlight-color: transparent;
}
.btn-force-quit:hover { background: var(--red-bg); border-color: var(--red); }

.quiz-header { display: flex; align-items: center; justify-content: space-between; margin-bottom: 8px; }
.q-label    { font-size: 0.7rem; font-weight: 700; color: var(--gray-500); letter-spacing: 1px; text-transform: uppercase; }
.q-fraction { font-size: 0.82rem; font-weight: 700; color: var(--blue); }
.progress-wrap { height: 5px; background: var(--gray-100); border-radius: 99px; overflow: hidden; margin-bottom: 24px; }
.progress-fill { height: 100%; background: linear-gradient(90deg, var(--blue), #7c3aed); border-radius: 99px; transition: width 0.4s cubic-bezier(0.4,0,0.2,1); }

.question-box {
  font-size: 1rem; font-weight: 600; color: var(--gray-900); line-height: 1.6;
  margin-bottom: 18px; padding: 14px 16px;
  background: #f8faff; border-left: 3px solid var(--blue);
  border-radius: 0 8px 8px 0;
}
.options-list { display: flex; flex-direction: column; gap: 9px; margin-bottom: 24px; }
.opt-item {
  display: flex; align-items: flex-start; gap: 11px;
  padding: 12px 14px; border: 1.5px solid var(--gray-200);
  border-radius: 10px; cursor: pointer; transition: all 0.18s;
  background: #fff; -webkit-tap-highlight-color: transparent;
  touch-action: manipulation; user-select: none;
}
.opt-item:hover  { border-color: #bfdbfe; background: var(--blue-light); }
.opt-item.chosen { border-color: var(--blue); background: var(--blue-light); box-shadow: 0 0 0 2px var(--blue-ring); }
.opt-item input  { display: none; }
.opt-badge {
  width: 28px; height: 28px; min-width: 28px; border: 1.5px solid var(--gray-300);
  border-radius: 6px; display: flex; align-items: center; justify-content: center;
  font-size: 0.7rem; font-weight: 700; color: var(--gray-400);
  flex-shrink: 0; transition: all 0.18s;
}
.opt-item.chosen .opt-badge { background: var(--blue); border-color: var(--blue); color: #fff; }
.opt-text { font-size: 0.9rem; color: var(--gray-700); line-height: 1.45; padding-top: 4px; font-weight: 500; }
.opt-item.chosen .opt-text { color: #1e3a8a; font-weight: 600; }

.btn-next {
  width: 100%; padding: 14px; background: var(--blue); color: #fff;
  font-size: 0.95rem; font-weight: 700; border: none; border-radius: 10px;
  cursor: pointer; transition: all 0.2s; font-family: inherit;
  display: flex; align-items: center; justify-content: center; gap: 8px;
  -webkit-tap-highlight-color: transparent; touch-action: manipulation;
}
.btn-next:hover  { background: var(--blue-dark); box-shadow: 0 4px 14px rgba(37,99,235,0.3); }
.btn-next:active { background: var(--blue-xd); }

/* ── Quit Confirmation Modal ─────────────────────────────── */
.modal-overlay {
  position: fixed; inset: 0; background: rgba(0,0,0,0.5);
  z-index: 400; display: none; align-items: center; justify-content: center;
  animation: fadeIn 0.2s ease;
}
.modal-overlay.open { display: flex; }
.modal-box {
  background: #fff; border-radius: var(--radius-lg); padding: 32px 28px;
  width: 90%; max-width: 400px; text-align: center;
  box-shadow: 0 20px 60px rgba(0,0,0,0.25);
  animation: popIn 0.3s cubic-bezier(0.34,1.56,0.64,1);
}
@keyframes popIn { from{transform:scale(0.85);opacity:0} to{transform:scale(1);opacity:1} }
.modal-icon { font-size: 2.5rem; margin-bottom: 12px; display: block; }
.modal-title { font-size: 1.2rem; font-weight: 800; color: var(--gray-900); margin-bottom: 8px; }
.modal-desc  { font-size: 0.85rem; color: var(--gray-500); line-height: 1.6; margin-bottom: 24px; }
.modal-desc strong { color: var(--red); font-weight: 700; }
.modal-actions { display: flex; gap: 10px; }
.btn-cancel {
  flex: 1; padding: 12px; background: #fff; border: 1.5px solid var(--gray-200);
  border-radius: 10px; font-size: 0.88rem; font-weight: 700; color: var(--gray-700);
  cursor: pointer; font-family: inherit; transition: all 0.2s;
}
.btn-cancel:hover { border-color: var(--blue); color: var(--blue); }
.btn-quit-confirm {
  flex: 1; padding: 12px; background: var(--red); border: none;
  border-radius: 10px; font-size: 0.88rem; font-weight: 700; color: #fff;
  cursor: pointer; font-family: inherit; transition: all 0.2s;
}
.btn-quit-confirm:hover { background: #b91c1c; }

/* ── Result ──────────────────────────────────────────────── */
#result-screen .card { padding: 36px 32px; }
.result-wrap { text-align: center; }
.result-trophy { font-size: 3.2rem; margin-bottom: 14px; display: block; animation: pop 0.5s cubic-bezier(0.34,1.56,0.64,1) both; }
@keyframes pop { from{transform:scale(0);opacity:0} to{transform:scale(1);opacity:1} }
.result-score { font-size: 3.8rem; font-weight: 900; color: var(--gray-900); line-height: 1; margin-bottom: 6px; animation: scalePop 0.6s cubic-bezier(0.16,1,0.3,1) both 0.15s; }
@keyframes scalePop { from{transform:scale(0.6);opacity:0} to{transform:scale(1);opacity:1} }
.result-label { font-size: 0.78rem; font-weight: 700; color: var(--gray-500); letter-spacing: 1.5px; text-transform: uppercase; margin-bottom: 22px; }
.result-stats { display: flex; justify-content: center; border: 1px solid var(--gray-200); border-radius: 12px; overflow: hidden; margin-bottom: 22px; }
.rs-item { flex: 1; padding: 14px 10px; text-align: center; border-right: 1px solid var(--gray-200); }
.rs-item:last-child { border-right: none; }
.rs-val { display: block; font-size: 1.3rem; font-weight: 800; color: var(--gray-900); }
.rs-lbl { display: block; font-size: 0.62rem; font-weight: 600; color: var(--gray-400); letter-spacing: 1px; text-transform: uppercase; margin-top: 2px; }
.result-msg { font-size: 0.84rem; color: var(--gray-500); margin-bottom: 24px; line-height: 1.6; background: var(--gray-50); border-radius: 8px; padding: 12px 16px; }
.result-actions { display: flex; gap: 10px; justify-content: center; flex-wrap: wrap; }
.btn-outline {
  padding: 11px 20px; border: 1.5px solid var(--gray-200);
  border-radius: 10px; background: #fff; color: var(--gray-700);
  font-size: 0.82rem; font-weight: 700; cursor: pointer;
  transition: all 0.2s; font-family: inherit; -webkit-tap-highlight-color: transparent;
}
.btn-outline:hover { border-color: var(--blue); color: var(--blue); background: var(--blue-light); }

/* ── Sync State ──────────────────────────────────────────── */
.sync-state { text-align: center; padding: 52px 0; }
.spinner { width: 38px; height: 38px; border: 3px solid var(--gray-200); border-top-color: var(--blue); border-radius: 50%; animation: spin 0.7s linear infinite; margin: 0 auto 14px; }
@keyframes spin { to{ transform: rotate(360deg); } }
.sync-state p { font-size: 0.82rem; color: var(--gray-400); font-weight: 500; }

/* ── Leaderboard ─────────────────────────────────────────── */
.lb-col { position: sticky; top: 70px; }
.lb-col .card { padding: 0; }
.lb-head { padding: 18px 20px 14px; border-bottom: 1px solid var(--gray-100); display: flex; align-items: center; justify-content: space-between; }
.lb-title { display: flex; align-items: center; gap: 7px; font-size: 0.98rem; font-weight: 800; color: var(--gray-900); }
.lb-refresh {
  width: 30px; height: 30px; border: 1px solid var(--gray-200); border-radius: 8px;
  background: #fff; display: flex; align-items: center; justify-content: center;
  cursor: pointer; color: var(--gray-500); font-size: 0.88rem; transition: all 0.2s;
  -webkit-tap-highlight-color: transparent;
}
.lb-refresh:hover { background: var(--gray-100); color: var(--blue); border-color: #bfdbfe; }
.lb-loading { padding: 36px 20px; text-align: center; color: var(--gray-400); font-size: 0.82rem; }
.lb-spinner { width: 26px; height: 26px; border: 2.5px solid var(--gray-200); border-top-color: var(--blue); border-radius: 50%; animation: spin 0.7s linear infinite; margin: 0 auto 10px; }
.lb-list { padding: 8px 12px 12px; }
.lb-item { display: flex; align-items: center; gap: 10px; padding: 10px 8px; border-radius: 10px; margin-bottom: 4px; transition: background 0.15s; }
.lb-item:last-child { margin-bottom: 0; }
.lb-item:hover { background: var(--gray-50); }
.lb-item.top-1 { background: linear-gradient(135deg,#fffbeb,#fef3c7); border: 1px solid #fde68a; }
.lb-item.top-2 { background: linear-gradient(135deg,#f8fafc,#f1f5f9); border: 1px solid #e2e8f0; }
.lb-item.top-3 { background: linear-gradient(135deg,#fff7f3,#fef2ec); border: 1px solid #fed7aa; }
.lb-rank     { font-size: 1rem; width: 26px; text-align: center; flex-shrink: 0; }
.lb-rank-num { font-size: 0.7rem; font-weight: 700; color: var(--gray-400); width: 26px; text-align: center; flex-shrink: 0; }
.lb-avatar { width: 32px; height: 32px; border-radius: 50%; background: linear-gradient(135deg,#dbeafe,#eff6ff); border: 1.5px solid #bfdbfe; display: flex; align-items: center; justify-content: center; font-size: 0.72rem; font-weight: 800; color: var(--blue); flex-shrink: 0; overflow: hidden; }
.lb-avatar img { width: 100%; height: 100%; object-fit: cover; border-radius: 50%; }
.lb-item.top-1 .lb-avatar { background: linear-gradient(135deg,#fef3c7,#fbbf24); border-color: #f59e0b; color: #78350f; }
.lb-item.top-2 .lb-avatar { background: linear-gradient(135deg,#f1f5f9,#cbd5e1); border-color: #94a3b8; color: #475569; }
.lb-item.top-3 .lb-avatar { background: linear-gradient(135deg,#fff7ed,#fed7aa); border-color: #fdba74; color: #9a3412; }
.lb-info { flex: 1; min-width: 0; }
.lb-name { font-size: 0.85rem; font-weight: 700; color: var(--gray-900); white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.lb-sub  { font-size: 0.65rem; color: var(--gray-400); font-weight: 500; margin-top: 1px; }
.lb-score-badge { padding: 3px 10px; border-radius: 20px; font-size: 0.76rem; font-weight: 800; flex-shrink: 0; }
.lb-item.top-1 .lb-score-badge { background: #f59e0b; color: #fff; }
.lb-item.top-2 .lb-score-badge { background: #64748b; color: #fff; }
.lb-item.top-3 .lb-score-badge { background: #ea580c; color: #fff; }
.lb-score-badge.default { background: var(--blue-light); color: var(--blue); border: 1px solid #bfdbfe; }
.lb-empty { padding: 32px 20px; text-align: center; color: var(--gray-400); font-size: 0.82rem; line-height: 1.7; }
.lb-empty-icon { font-size: 1.8rem; margin-bottom: 8px; display: block; }

/* Mobile leaderboard toggle */
.lb-toggle-btn {
  display: none; width: 100%; padding: 12px; background: #fff;
  border: 1.5px solid var(--gray-200); border-radius: 10px;
  font-size: 0.88rem; font-weight: 700; color: var(--gray-700);
  cursor: pointer; font-family: inherit;
  align-items: center; justify-content: space-between;
  transition: all 0.2s; -webkit-tap-highlight-color: transparent;
}
.lb-toggle-btn:hover { border-color: var(--blue); color: var(--blue); }
.lb-toggle-arrow { transition: transform 0.3s; font-size: 0.7rem; }
.lb-toggle-btn.open .lb-toggle-arrow { transform: rotate(180deg); }
.lb-collapsible { overflow: hidden; transition: max-height 0.35s cubic-bezier(0.4,0,0.2,1); }

/* ── Shake ───────────────────────────────────────────────── */
@keyframes shake { 0%,100%{transform:translateX(0)} 20%{transform:translateX(-5px)} 40%{transform:translateX(5px)} 60%{transform:translateX(-3px)} 80%{transform:translateX(3px)} }

/* ── Toast ───────────────────────────────────────────────── */
.toast {
  position: fixed; bottom: 24px; right: 24px; z-index: 500;
  background: var(--gray-900); color: #fff;
  padding: 12px 18px; border-radius: 10px;
  font-size: 0.82rem; font-weight: 600;
  box-shadow: 0 8px 24px rgba(0,0,0,0.2);
  animation: toastIn 0.3s cubic-bezier(0.34,1.56,0.64,1);
  display: flex; align-items: center; gap: 8px; max-width: 320px;
}
.toast.success { background: var(--green); }
.toast.error   { background: var(--red); }
@keyframes toastIn { from{transform:translateY(20px);opacity:0} to{transform:translateY(0);opacity:1} }
@keyframes toastOut { to{transform:translateY(20px);opacity:0} }
.toast.out { animation: toastOut 0.25s ease forwards; }

/* ── Responsive ──────────────────────────────────────────── */
@media (max-width: 900px) {
  .page-wrap { grid-template-columns: 1fr; padding: 20px 14px 50px; gap: 16px; }
  .lb-col { position: static; order: 2; }
  .main-col { order: 1; }
  .lb-toggle-btn { display: flex; }
  .lb-collapsible { max-height: 0; }
  .lb-collapsible.open { max-height: 1200px; }
  .lb-col .card { border-radius: 14px; overflow: hidden; }
}
@media (max-width: 600px) {
  .topbar { padding: 0 14px; height: 50px; }
  .topbar-title { display: none; }
  .page-wrap { padding: 14px 12px 48px; gap: 14px; }
  .main-col .card { padding: 22px 18px 26px; }
  #quiz-view .card { padding: 20px 16px 24px; }
  #result-screen .card { padding: 28px 18px; }
  .form-input { font-size: 16px; padding: 12px 13px; }
  .question-box { font-size: 0.92rem; padding: 12px 13px; }
  .opt-item { padding: 11px 12px; gap: 10px; }
  .opt-text { font-size: 0.86rem; }
  .result-score { font-size: 3rem; }
  .timer-display { font-size: 1.1rem; }
}