:root {
  --primary: #7C3AED;
  --primary-strong: #6D28D9;
  --on-primary: #FFFFFF;
  --secondary: #8B5CF6;
  --accent: #059669;
  --accent-strong: #047857;
  --danger: #DC2626;
  --warn: #D97706;
  --info: #2563EB;
  --bg: #FAF5FF;
  --bg-soft: #F3EBFC;
  --fg: #0F172A;
  --muted-fg: #55627A;
  --card: #FFFFFF;
  --card-fg: #0F172A;
  --border: #EFE7FC;
  --border-strong: #DDD0F5;
  --ring: #7C3AED;
  --correct-bg: #ECFDF5;
  --correct-bd: #A7F3D0;
  --correct-fg: #065F46;
  --wrong-bg: #FEF2F2;
  --wrong-bd: #FECACA;
  --wrong-fg: #991B1B;
  --shadow-sm: 0 1px 2px rgba(80, 44, 140, .06), 0 2px 8px rgba(80, 44, 140, .07);
  --shadow-md: 0 4px 14px rgba(80, 44, 140, .10), 0 2px 4px rgba(80, 44, 140, .06);
  --shadow-lg: 0 12px 32px rgba(80, 44, 140, .16), 0 4px 8px rgba(80, 44, 140, .08);
  --shadow-primary: 0 8px 20px rgba(124, 58, 237, .32);
  --radius: 16px;
  --radius-lg: 22px;
  --radius-pill: 999px;
  --space-1: 4px; --space-2: 8px; --space-3: 12px; --space-4: 16px;
  --space-5: 24px; --space-6: 32px; --space-7: 48px; --space-8: 64px;
  --ease-out: cubic-bezier(.22, 1, .36, 1);
  --ease-spring: cubic-bezier(.34, 1.56, .64, 1);
  --t-fast: 160ms; --t-med: 240ms; --t-slow: 420ms;
}

[data-theme="dark"] {
  --primary: #A78BFA;
  --primary-strong: #8B5CF6;
  --on-primary: #150B2E;
  --secondary: #C4B5FD;
  --accent: #34D399;
  --accent-strong: #10B981;
  --danger: #F87171;
  --warn: #FBBF24;
  --info: #60A5FA;
  --bg: #100B1A;
  --bg-soft: #191028;
  --fg: #F1EDFB;
  --muted-fg: #A79FC4;
  --card: #1A1229;
  --card-fg: #F1EDFB;
  --border: #2C2143;
  --border-strong: #3B2D58;
  --ring: #A78BFA;
  --correct-bg: #0A2E22;
  --correct-bd: #14684A;
  --correct-fg: #6EE7B7;
  --wrong-bg: #341418;
  --wrong-bd: #7A2A31;
  --wrong-fg: #FCA5A5;
  --shadow-sm: 0 1px 2px rgba(0, 0, 0, .4), 0 2px 8px rgba(0, 0, 0, .3);
  --shadow-md: 0 4px 14px rgba(0, 0, 0, .45), 0 2px 4px rgba(0, 0, 0, .35);
  --shadow-lg: 0 12px 32px rgba(0, 0, 0, .55), 0 4px 8px rgba(0, 0, 0, .4);
  --shadow-primary: 0 8px 20px rgba(139, 92, 246, .28);
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  font-family: "Be Vietnam Pro", system-ui, -apple-system, "Segoe UI", sans-serif;
  font-size: 16px;
  line-height: 1.6;
  color: var(--fg);
  background:
    radial-gradient(900px 480px at 85% -10%, color-mix(in srgb, var(--secondary) 16%, transparent), transparent 70%),
    radial-gradient(700px 420px at -10% 0%, color-mix(in srgb, var(--accent) 10%, transparent), transparent 70%),
    var(--bg);
  background-attachment: fixed;
  min-height: 100dvh;
  display: flex;
  flex-direction: column;
  -webkit-font-smoothing: antialiased;
  transition: background-color var(--t-med) ease, color var(--t-med) ease;
}

:focus-visible {
  outline: 3px solid var(--ring);
  outline-offset: 2px;
  border-radius: 6px;
}

button { font: inherit; color: inherit; cursor: pointer; }
::selection { background: color-mix(in srgb, var(--primary) 25%, transparent); }

.topbar {
  position: sticky;
  top: 0;
  z-index: 40;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-4);
  padding: var(--space-3) var(--space-5);
  background: color-mix(in srgb, var(--bg) 82%, transparent);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  border-bottom: 1px solid var(--border);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
  color: var(--fg);
  font-weight: 800;
  font-size: 1.2rem;
  letter-spacing: -.02em;
}

.brand-mark {
  display: grid;
  place-items: center;
  width: 38px;
  height: 38px;
  border-radius: 12px;
  color: #fff;
  background: linear-gradient(135deg, var(--primary), var(--secondary));
  box-shadow: var(--shadow-primary);
  transition: transform var(--t-med) var(--ease-spring);
}

.brand:hover .brand-mark { transform: rotate(-8deg) scale(1.06); }
.brand-mark svg { width: 20px; height: 20px; }
.brand-text b { color: var(--primary); }

.icon-btn {
  display: grid;
  place-items: center;
  width: 44px;
  height: 44px;
  border: 1px solid var(--border);
  border-radius: 14px;
  background: var(--card);
  color: var(--fg);
  box-shadow: var(--shadow-sm);
  transition: transform var(--t-fast) var(--ease-spring), box-shadow var(--t-fast) ease, background-color var(--t-fast) ease;
}

.icon-btn:hover { transform: translateY(-2px); box-shadow: var(--shadow-md); }
.icon-btn:active { transform: scale(.94); }
.icon-btn svg { width: 20px; height: 20px; }

#themeToggle .ico-moon { display: none; }
[data-theme="dark"] #themeToggle .ico-sun { display: none; }
[data-theme="dark"] #themeToggle .ico-moon { display: block; }

.container {
  width: min(1080px, 100%);
  margin: 0 auto;
  padding: var(--space-6) var(--space-5) var(--space-8);
  flex: 1;
}

.footer {
  text-align: center;
  color: var(--muted-fg);
  font-size: .85rem;
  padding: var(--space-5) var(--space-4) calc(var(--space-5) + env(safe-area-inset-bottom, 0px));
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  min-height: 46px;
  padding: 10px 22px;
  border: 1px solid transparent;
  border-radius: var(--radius-pill);
  font-weight: 600;
  font-size: .98rem;
  text-decoration: none;
  white-space: nowrap;
  transition: transform var(--t-fast) var(--ease-spring), box-shadow var(--t-fast) ease, background-color var(--t-fast) ease, opacity var(--t-fast) ease;
}

.btn svg { width: 18px; height: 18px; flex: none; }
.btn:active { transform: scale(.96); }
.btn:disabled { opacity: .45; cursor: not-allowed; }

.btn-primary {
  background: linear-gradient(135deg, var(--primary), var(--secondary));
  color: var(--on-primary);
  box-shadow: var(--shadow-primary);
}
.btn-primary:hover { transform: translateY(-2px); filter: brightness(1.06); }

.btn-accent {
  background: linear-gradient(135deg, var(--accent), color-mix(in srgb, var(--accent) 70%, var(--info)));
  color: #fff;
  box-shadow: 0 8px 20px rgba(5, 150, 105, .28);
}
.btn-accent:hover { transform: translateY(-2px); filter: brightness(1.05); }

.btn-ghost {
  background: var(--card);
  color: var(--fg);
  border-color: var(--border-strong);
  box-shadow: var(--shadow-sm);
}
.btn-ghost:hover { transform: translateY(-2px); box-shadow: var(--shadow-md); background: var(--bg-soft); }

.btn-danger { background: var(--danger); color: #fff; }
.btn-danger:hover { transform: translateY(-2px); filter: brightness(1.05); }

.hero { margin-bottom: var(--space-7); animation: rise var(--t-slow) var(--ease-out) both; }
.hero h1 {
  margin: 0 0 6px;
  font-size: clamp(1.7rem, 4vw, 2.5rem);
  font-weight: 800;
  letter-spacing: -.03em;
  line-height: 1.2;
}
.hero h1 em {
  font-style: normal;
  background: linear-gradient(90deg, var(--primary), var(--secondary));
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}
.hero p { margin: 0; color: var(--muted-fg); max-width: 56ch; }

.exam-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: var(--space-5);
}

.exam-card {
  position: relative;
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
  padding: var(--space-5);
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-sm);
  overflow: hidden;
  animation: rise var(--t-slow) var(--ease-out) both;
  transition: transform var(--t-med) var(--ease-spring), box-shadow var(--t-med) ease, border-color var(--t-med) ease;
}

.exam-card::before {
  content: "";
  position: absolute;
  inset: 0 0 auto 0;
  height: 5px;
  background: linear-gradient(90deg, var(--primary), var(--secondary));
  transform: scaleX(0);
  transform-origin: left;
  transition: transform var(--t-slow) var(--ease-out);
}

.exam-card:hover { transform: translateY(-6px); box-shadow: var(--shadow-lg); border-color: var(--border-strong); }
.exam-card:hover::before { transform: scaleX(1); }

.exam-card .card-top {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-3);
}

.chip {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 4px 12px;
  border-radius: var(--radius-pill);
  font-size: .8rem;
  font-weight: 600;
  background: color-mix(in srgb, var(--primary) 12%, var(--card));
  color: var(--primary-strong);
  border: 1px solid color-mix(in srgb, var(--primary) 22%, transparent);
}

[data-theme="dark"] .chip { color: var(--secondary); }
.chip-accent { background: color-mix(in srgb, var(--accent) 14%, var(--card)); color: var(--accent-strong); border-color: color-mix(in srgb, var(--accent) 30%, transparent); }
[data-theme="dark"] .chip-accent { color: var(--accent); }
.chip-warn { background: color-mix(in srgb, var(--warn) 14%, var(--card)); color: var(--warn); border-color: color-mix(in srgb, var(--warn) 30%, transparent); }
.chip-danger { background: color-mix(in srgb, var(--danger) 12%, var(--card)); color: var(--danger); border-color: color-mix(in srgb, var(--danger) 26%, transparent); }

.exam-card h3 { margin: 0; font-size: 1.12rem; font-weight: 700; letter-spacing: -.01em; line-height: 1.35; }
.exam-card .desc { margin: 0; color: var(--muted-fg); font-size: .92rem; flex: 1; display: -webkit-box; -webkit-line-clamp: 2; -webkit-box-orient: vertical; overflow: hidden; }

.exam-meta {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-2) var(--space-4);
  color: var(--muted-fg);
  font-size: .86rem;
  font-weight: 500;
}

.exam-meta span { display: inline-flex; align-items: center; gap: 6px; }
.exam-meta svg { width: 16px; height: 16px; }

.card-actions { display: flex; gap: var(--space-3); flex-wrap: wrap; align-items: center; }

.resume-note {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: .86rem;
  color: var(--warn);
  font-weight: 600;
}
.resume-note svg { width: 16px; height: 16px; flex: none; }

.best-score {
  position: absolute;
  top: var(--space-4);
  right: var(--space-4);
  font-size: .78rem;
  font-weight: 700;
  color: var(--muted-fg);
  background: var(--bg-soft);
  border: 1px solid var(--border);
  padding: 3px 10px;
  border-radius: var(--radius-pill);
}

.empty-state {
  text-align: center;
  padding: var(--space-8) var(--space-5);
  color: var(--muted-fg);
  animation: rise var(--t-slow) var(--ease-out) both;
}
.empty-state svg { width: 56px; height: 56px; opacity: .5; margin-bottom: var(--space-3); }

.quiz-shell { animation: rise var(--t-med) var(--ease-out) both; }

.quiz-head {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  margin-bottom: var(--space-4);
  flex-wrap: wrap;
}

.quiz-title {
  flex: 1;
  min-width: 200px;
  font-weight: 700;
  font-size: 1.05rem;
  letter-spacing: -.01em;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.timer {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 8px 16px;
  border-radius: var(--radius-pill);
  background: var(--card);
  border: 1px solid var(--border-strong);
  font-weight: 700;
  font-variant-numeric: tabular-nums;
  font-size: .95rem;
  box-shadow: var(--shadow-sm);
}

.timer svg { width: 17px; height: 17px; color: var(--muted-fg); }
.timer.warn { color: var(--danger); border-color: color-mix(in srgb, var(--danger) 45%, transparent); animation: pulse 1.1s ease infinite; }
.timer.warn svg { color: var(--danger); }

.progress-wrap {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  margin-bottom: var(--space-5);
}

.progress-count { font-weight: 700; font-size: .9rem; font-variant-numeric: tabular-nums; color: var(--muted-fg); white-space: nowrap; }

.progress-track {
  flex: 1;
  height: 10px;
  border-radius: var(--radius-pill);
  background: var(--bg-soft);
  border: 1px solid var(--border);
  overflow: hidden;
}

.progress-fill {
  height: 100%;
  border-radius: var(--radius-pill);
  background: linear-gradient(90deg, var(--primary), var(--secondary));
  box-shadow: 0 0 12px color-mix(in srgb, var(--primary) 55%, transparent);
  transition: width var(--t-slow) var(--ease-out);
}

.question-card {
  position: relative;
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-md);
  padding: var(--space-6);
  margin-bottom: var(--space-5);
}

.q-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-3);
  margin-bottom: var(--space-4);
}

.q-number { font-size: .85rem; font-weight: 700; color: var(--primary-strong); letter-spacing: .02em; }
[data-theme="dark"] .q-number { color: var(--secondary); }

.flag-btn {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  min-height: 40px;
  padding: 6px 14px;
  border-radius: var(--radius-pill);
  border: 1px solid var(--border-strong);
  background: transparent;
  color: var(--muted-fg);
  font-weight: 600;
  font-size: .85rem;
  transition: all var(--t-fast) ease;
}

.flag-btn svg { width: 16px; height: 16px; }
.flag-btn:hover { border-color: var(--warn); color: var(--warn); }
.flag-btn.active {
  background: color-mix(in srgb, var(--warn) 15%, var(--card));
  border-color: color-mix(in srgb, var(--warn) 50%, transparent);
  color: var(--warn);
}

.q-text {
  font-size: 1.15rem;
  font-weight: 600;
  line-height: 1.55;
  margin: 0 0 var(--space-5);
  letter-spacing: -.01em;
  white-space: pre-wrap;
}

.q-image {
  display: block;
  max-width: min(480px, 100%);
  border-radius: var(--radius);
  border: 1px solid var(--border);
  margin: 0 0 var(--space-5);
  box-shadow: var(--shadow-sm);
}

.options { display: grid; gap: var(--space-3); }

.option {
  display: flex;
  align-items: center;
  gap: var(--space-4);
  width: 100%;
  text-align: left;
  padding: var(--space-4) var(--space-4);
  min-height: 58px;
  background: var(--card);
  border: 2px solid var(--border);
  border-radius: var(--radius);
  font-size: 1rem;
  font-weight: 500;
  line-height: 1.45;
  transition: border-color var(--t-fast) ease, background-color var(--t-fast) ease, transform var(--t-fast) var(--ease-spring), box-shadow var(--t-fast) ease;
}

.option:hover:not(:disabled) {
  border-color: var(--border-strong);
  background: var(--bg-soft);
  transform: translateX(4px);
}

.option:active:not(:disabled) { transform: scale(.985); }

.option-letter {
  display: grid;
  place-items: center;
  flex: none;
  width: 36px;
  height: 36px;
  border-radius: 12px;
  font-weight: 700;
  font-size: .92rem;
  background: var(--bg-soft);
  color: var(--muted-fg);
  border: 1px solid var(--border);
  transition: all var(--t-fast) ease;
}

.option.selected {
  border-color: var(--primary);
  background: color-mix(in srgb, var(--primary) 7%, var(--card));
  box-shadow: 0 0 0 4px color-mix(in srgb, var(--primary) 14%, transparent);
}

.option.selected .option-letter {
  background: linear-gradient(135deg, var(--primary), var(--secondary));
  color: var(--on-primary);
  border-color: transparent;
  transform: scale(1.08);
}

.option.correct { border-color: var(--accent); background: var(--correct-bg); }
.option.correct .option-letter { background: var(--accent); color: #fff; border-color: transparent; }
.option.wrong { border-color: var(--danger); background: var(--wrong-bg); }
.option.wrong .option-letter { background: var(--danger); color: #fff; border-color: transparent; }
.option .opt-mark { margin-left: auto; width: 22px; height: 22px; flex: none; }
.option .opt-mark.check { color: var(--accent-strong); }
.option .opt-mark.x { color: var(--danger); }

.q-anim { animation: slideIn var(--t-med) var(--ease-out) both; }
.q-anim.back { animation-name: slideInBack; }

.quiz-foot {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-3);
  flex-wrap: wrap;
  margin-bottom: var(--space-5);
}

.foot-nav { display: flex; gap: var(--space-3); }

.navigator {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: var(--space-5);
  box-shadow: var(--shadow-sm);
}

.navigator h4 {
  margin: 0 0 var(--space-4);
  font-size: .92rem;
  font-weight: 700;
  display: flex;
  align-items: center;
  gap: 8px;
}

.navigator h4 svg { width: 17px; height: 17px; color: var(--muted-fg); }

.nav-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(44px, 1fr));
  gap: var(--space-2);
}

.nav-cell {
  display: grid;
  place-items: center;
  height: 44px;
  border-radius: 12px;
  border: 1.5px solid var(--border-strong);
  background: var(--card);
  font-weight: 700;
  font-size: .85rem;
  font-variant-numeric: tabular-nums;
  color: var(--muted-fg);
  transition: all var(--t-fast) var(--ease-spring);
}

.nav-cell:hover { transform: translateY(-2px) scale(1.05); border-color: var(--primary); color: var(--primary); }
.nav-cell.answered { background: color-mix(in srgb, var(--primary) 12%, var(--card)); border-color: color-mix(in srgb, var(--primary) 40%, transparent); color: var(--primary-strong); }
[data-theme="dark"] .nav-cell.answered { color: var(--secondary); }
.nav-cell.flagged { position: relative; }
.nav-cell.flagged::after {
  content: "";
  position: absolute;
  top: 5px;
  right: 5px;
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--warn);
}
.nav-cell.current { border-color: var(--primary); box-shadow: 0 0 0 3px color-mix(in srgb, var(--primary) 22%, transparent); color: var(--primary-strong); }

.nav-legend {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-2) var(--space-4);
  margin-top: var(--space-4);
  font-size: .8rem;
  color: var(--muted-fg);
  font-weight: 500;
}

.nav-legend span { display: inline-flex; align-items: center; gap: 6px; }
.nav-legend i { width: 14px; height: 14px; border-radius: 5px; border: 1.5px solid var(--border-strong); display: inline-block; }
.nav-legend i.l-answered { background: color-mix(in srgb, var(--primary) 12%, var(--card)); border-color: color-mix(in srgb, var(--primary) 40%, transparent); }
.nav-legend i.l-flag { background: var(--warn); border-color: var(--warn); border-radius: 50%; width: 10px; height: 10px; }

.result-hero {
  text-align: center;
  padding: var(--space-7) var(--space-5) var(--space-6);
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-md);
  margin-bottom: var(--space-6);
  animation: rise var(--t-slow) var(--ease-out) both;
}

.score-ring-wrap { position: relative; width: 168px; height: 168px; margin: 0 auto var(--space-4); }

.score-ring { width: 100%; height: 100%; transform: rotate(-90deg); }
.score-ring .track { fill: none; stroke: var(--bg-soft); stroke-width: 13; }
.score-ring .bar {
  fill: none;
  stroke: url(#scoreGrad);
  stroke-width: 13;
  stroke-linecap: round;
  transition: stroke-dashoffset 1.1s var(--ease-out);
}

.score-ring-label {
  position: absolute;
  inset: 0;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 2px;
}

.score-ring-label .big { font-size: 2.35rem; font-weight: 800; letter-spacing: -.04em; font-variant-numeric: tabular-nums; line-height: 1; }
.score-ring-label .small { font-size: .8rem; color: var(--muted-fg); font-weight: 600; }

.result-hero h2 { margin: 0 0 4px; font-size: 1.5rem; font-weight: 800; letter-spacing: -.02em; }
.result-hero .verdict { color: var(--muted-fg); margin: 0 0 var(--space-5); font-weight: 500; }

.result-stats {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(130px, 1fr));
  gap: var(--space-3);
  max-width: 620px;
  margin: 0 auto var(--space-5);
}

.stat {
  padding: var(--space-4) var(--space-3);
  border-radius: var(--radius);
  border: 1px solid var(--border);
  background: var(--bg-soft);
}

.stat b { display: block; font-size: 1.35rem; font-weight: 800; letter-spacing: -.02em; font-variant-numeric: tabular-nums; }
.stat span { font-size: .8rem; color: var(--muted-fg); font-weight: 600; }
.stat.ok b { color: var(--accent-strong); }
.stat.bad b { color: var(--danger); }
.stat.skip b { color: var(--muted-fg); }

.result-actions { display: flex; gap: var(--space-3); justify-content: center; flex-wrap: wrap; }

.filter-row { display: flex; gap: var(--space-2); flex-wrap: wrap; margin-bottom: var(--space-5); }

.filter-chip {
  padding: 8px 18px;
  min-height: 40px;
  border-radius: var(--radius-pill);
  border: 1.5px solid var(--border-strong);
  background: var(--card);
  font-weight: 600;
  font-size: .88rem;
  color: var(--muted-fg);
  transition: all var(--t-fast) ease;
}

.filter-chip:hover { border-color: var(--primary); color: var(--primary); }
.filter-chip.active { background: var(--primary); border-color: var(--primary); color: var(--on-primary); box-shadow: var(--shadow-primary); }

.review-list { display: grid; gap: var(--space-4); }

.review-card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: var(--space-5);
  box-shadow: var(--shadow-sm);
  animation: rise var(--t-slow) var(--ease-out) both;
}

.review-card.ok { border-left: 5px solid var(--accent); }
.review-card.bad { border-left: 5px solid var(--danger); }

.review-q { font-weight: 600; font-size: 1.02rem; margin: 0 0 var(--space-3); white-space: pre-wrap; }

.review-opt {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 10px 14px;
  border-radius: 12px;
  font-size: .94rem;
  margin-bottom: 6px;
  border: 1.5px solid var(--border);
  color: var(--muted-fg);
}

.review-opt svg { width: 18px; height: 18px; flex: none; }
.review-opt.r-correct { border-color: var(--accent); background: var(--correct-bg); color: var(--correct-fg); font-weight: 600; }
.review-opt.r-wrong { border-color: var(--danger); background: var(--wrong-bg); color: var(--wrong-fg); font-weight: 600; }

.explain {
  margin-top: var(--space-3);
  padding: var(--space-4);
  border-radius: var(--radius);
  background: color-mix(in srgb, var(--info) 8%, var(--card));
  border: 1px solid color-mix(in srgb, var(--info) 25%, transparent);
  font-size: .93rem;
  color: var(--fg);
}

.explain b { color: var(--info); display: block; margin-bottom: 4px; font-size: .82rem; text-transform: uppercase; letter-spacing: .06em; }
[data-theme="dark"] .explain b { color: var(--info); }

.modal-root {
  position: fixed;
  inset: 0;
  z-index: 90;
  display: grid;
  place-items: center;
  padding: var(--space-5);
  background: color-mix(in srgb, #0B0614 55%, transparent);
  backdrop-filter: blur(6px);
  -webkit-backdrop-filter: blur(6px);
  animation: fadeIn var(--t-fast) ease both;
}

.modal {
  width: min(440px, 100%);
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-lg);
  padding: var(--space-6);
  text-align: center;
  animation: pop var(--t-med) var(--ease-spring) both;
}

.modal .modal-ico {
  display: grid;
  place-items: center;
  width: 58px;
  height: 58px;
  margin: 0 auto var(--space-4);
  border-radius: 18px;
  background: color-mix(in srgb, var(--warn) 15%, var(--card));
  color: var(--warn);
}

.modal .modal-ico svg { width: 28px; height: 28px; }
.modal h3 { margin: 0 0 8px; font-size: 1.2rem; font-weight: 800; letter-spacing: -.01em; }
.modal p { margin: 0 0 var(--space-5); color: var(--muted-fg); font-size: .95rem; }
.modal .modal-actions { display: grid; gap: var(--space-2); }

.toast-root {
  position: fixed;
  bottom: calc(var(--space-5) + env(safe-area-inset-bottom, 0px));
  left: 50%;
  transform: translateX(-50%);
  z-index: 100;
  display: grid;
  gap: var(--space-2);
  width: max-content;
  max-width: calc(100vw - 32px);
}

.toast {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 12px 20px;
  border-radius: var(--radius-pill);
  background: var(--fg);
  color: var(--bg);
  font-weight: 600;
  font-size: .92rem;
  box-shadow: var(--shadow-lg);
  animation: toastIn var(--t-med) var(--ease-spring) both;
}

.toast.out { animation: toastOut var(--t-fast) ease both; }

#confetti {
  position: fixed;
  inset: 0;
  z-index: 80;
  pointer-events: none;
}

.kbd-hint {
  text-align: center;
  color: var(--muted-fg);
  font-size: .8rem;
  margin-top: var(--space-4);
}

.kbd-hint kbd {
  font-family: inherit;
  font-size: .75rem;
  font-weight: 700;
  padding: 2px 7px;
  border-radius: 6px;
  border: 1px solid var(--border-strong);
  background: var(--card);
  box-shadow: 0 2px 0 var(--border-strong);
  margin: 0 2px;
}

.skeleton {
  position: relative;
  overflow: hidden;
  background: var(--bg-soft);
  border-radius: var(--radius-lg);
}

.skeleton::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(90deg, transparent, color-mix(in srgb, var(--card) 70%, transparent), transparent);
  animation: shimmer 1.3s infinite;
}

.skeleton-card { height: 220px; }

@keyframes rise {
  from { opacity: 0; transform: translateY(18px); }
  to { opacity: 1; transform: translateY(0); }
}

@keyframes slideIn {
  from { opacity: 0; transform: translateX(34px); }
  to { opacity: 1; transform: translateX(0); }
}

@keyframes slideInBack {
  from { opacity: 0; transform: translateX(-34px); }
  to { opacity: 1; transform: translateX(0); }
}

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

@keyframes pop {
  from { opacity: 0; transform: scale(.86) translateY(12px); }
  to { opacity: 1; transform: scale(1) translateY(0); }
}

@keyframes pulse {
  0%, 100% { transform: scale(1); }
  50% { transform: scale(1.045); }
}

@keyframes toastIn {
  from { opacity: 0; transform: translateY(16px) scale(.94); }
  to { opacity: 1; transform: translateY(0) scale(1); }
}

@keyframes toastOut {
  from { opacity: 1; }
  to { opacity: 0; transform: translateY(8px) scale(.96); }
}

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

@media (max-width: 640px) {
  .container { padding: var(--space-5) var(--space-4) var(--space-7); }
  .question-card { padding: var(--space-4); }
  .q-text { font-size: 1.06rem; }
  .quiz-foot { gap: var(--space-2); }
  .btn { flex: 1; justify-content: center; }
  .foot-nav { width: 100%; }
  .quiz-head .timer { order: 3; }
  .result-hero { padding: var(--space-5) var(--space-4); }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: .01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: .01ms !important;
    scroll-behavior: auto !important;
  }
}