:root {
  color-scheme: light;
  --bg: #f4efe7;
  --bg-2: #ede4d8;
  --panel: rgba(255, 250, 243, 0.9);
  --panel-strong: rgba(255, 250, 243, 0.98);
  --line: rgba(22, 33, 43, 0.12);
  --text: #16212b;
  --muted: #63707a;
  --accent: #9b5c37;
  --accent-2: #135b57;
  --good: #20744f;
  --bad: #b42318;
  --shadow: 0 12px 28px rgba(31, 40, 47, 0.08);
  --radius: 24px;
  --radius-sm: 16px;
  --mono: "SFMono-Regular", Consolas, "Liberation Mono", monospace;
  --sans: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  --serif: var(--sans);
}

* {
  box-sizing: border-box;
}

html, body {
  min-height: 100%;
}

body {
  margin: 0;
  font-family: var(--sans);
  font-size: 15px;
  line-height: 1.7;
  padding-top: 56px;
  background:
    radial-gradient(circle at top left, rgba(19, 91, 87, 0.12), transparent 28%),
    radial-gradient(circle at top right, rgba(155, 92, 55, 0.12), transparent 30%),
    linear-gradient(180deg, var(--bg) 0%, var(--bg-2) 100%);
  color: var(--text);
  overflow-x: hidden;
}

body.theme-dark {
  color-scheme: dark;
  --bg: #071015;
  --bg-2: #0d1720;
  --panel: rgba(10, 18, 24, 0.9);
  --panel-strong: rgba(13, 23, 32, 0.96);
  --line: rgba(255, 255, 255, 0.1);
  --text: #ecf1f4;
  --muted: #a2b1bd;
  --accent: #d7a16f;
  --accent-2: #6bd0c2;
  --good: #7bd79a;
  --bad: #ff8f8f;
  --shadow: 0 18px 36px rgba(0, 0, 0, 0.26);
  background:
    radial-gradient(circle at top left, rgba(107, 208, 194, 0.12), transparent 28%),
    radial-gradient(circle at top right, rgba(215, 161, 111, 0.12), transparent 30%),
    linear-gradient(180deg, var(--bg) 0%, var(--bg-2) 100%);
}

button, input {
  font: inherit;
}

button {
  border: 0;
}

.shell {
  position: relative;
  z-index: 1;
  width: min(1360px, calc(100vw - 32px));
  margin: 0 auto;
  padding: 28px 0 48px;
}

.hero {
  display: grid;
  grid-template-columns: minmax(0, 1.6fr) minmax(260px, 0.9fr);
  gap: 24px;
  align-items: stretch;
  margin-bottom: 22px;
}

.hero-topbar {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: 16px;
}

.site-alert {
  position: fixed;
  inset: 0 0 auto 0;
  z-index: 40;
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 12px 18px;
  border-bottom: 1px solid var(--line);
  background: rgba(255, 250, 243, 0.94);
  backdrop-filter: blur(12px);
  box-shadow: 0 6px 18px rgba(31, 40, 47, 0.06);
}

.site-alert-label {
  flex: 0 0 auto;
  padding: 6px 10px;
  border-radius: 999px;
  background: rgba(19, 91, 87, 0.1);
  color: var(--accent-2);
  font-size: 0.72rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.12em;
}

.site-alert-text {
  color: var(--text);
  font-size: 0.88rem;
  line-height: 1.4;
}

.site-alert-text a {
  color: inherit;
  font-weight: 700;
  text-decoration: underline;
  text-decoration-color: rgba(19, 91, 87, 0.45);
  text-underline-offset: 2px;
}

body.theme-dark .site-alert-text a {
  text-decoration-color: rgba(107, 208, 194, 0.55);
}

body.theme-dark .site-alert {
  background: rgba(10, 18, 24, 0.96);
}

body.theme-dark .site-alert-label {
  background: rgba(107, 208, 194, 0.12);
  color: #90e4d8;
}

.theme-toggle {
  flex: 0 0 auto;
  padding: 10px 14px;
  border-radius: 999px;
  border: 1px solid rgba(22, 33, 43, 0.1);
  background: rgba(255, 255, 255, 0.62);
  color: var(--text);
  cursor: pointer;
  transition: transform 0.18s ease, background 0.18s ease, border-color 0.18s ease;
}

.theme-toggle:hover {
  transform: translateY(-1px);
  border-color: rgba(19, 91, 87, 0.28);
}

body.theme-dark .theme-toggle {
  background: rgba(255, 255, 255, 0.06);
  border-color: rgba(255, 255, 255, 0.1);
}

.hero-copy, .mode-card, .panel, .question-card, .rail, .stat-card {
  background: linear-gradient(180deg, rgba(255, 250, 243, 0.94), rgba(247, 240, 230, 0.92));
  border: 1px solid var(--line);
  box-shadow: var(--shadow);
  backdrop-filter: blur(18px);
}

.hero-copy {
  border-radius: 24px;
  padding: 26px;
  position: relative;
  overflow: hidden;
}

.hero-copy::after {
  content: '';
  position: absolute;
  inset: auto -18% -45% auto;
  width: 340px;
  height: 340px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(19, 91, 87, 0.12), transparent 64%);
  pointer-events: none;
}

.eyebrow, .section-kicker, .mode-label {
  margin: 0 0 10px;
  text-transform: uppercase;
  letter-spacing: 0.18em;
  color: var(--accent-2);
  font-size: 0.72rem;
}

h1, h2, h3 {
  margin: 0;
  font-family: var(--sans);
  font-weight: 700;
  line-height: 1.12;
  letter-spacing: -0.01em;
}

h1 {
  font-size: clamp(2rem, 3.2vw, 3.4rem);
  max-width: 14ch;
}

h2 {
  font-size: clamp(1.2rem, 1.8vw, 1.65rem);
}

h3 {
  font-size: 1rem;
}

.lede, .panel-note, .mode-card p, .question-meta, .toolbar-stats, .results-subtitle, .muted {
  color: var(--muted);
  line-height: 1.75;
}

.lede {
  max-width: 66ch;
  font-size: 1rem;
  margin: 16px 0 0;
}

.hero-stat-grid {
  display: grid;
  gap: 14px;
}

.stat-card {
  border-radius: 20px;
  padding: 16px 16px 14px;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  min-height: 100px;
}

.stat-card span {
  color: var(--muted);
  font-size: 0.78rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
}

.stat-card strong {
  font-family: var(--sans);
  font-size: 1.55rem;
  margin-top: 8px;
}

.panel {
  border-radius: 24px;
  padding: 22px;
}

.panel-head, .toolbar {
  display: flex;
  justify-content: space-between;
  gap: 16px;
  align-items: end;
  margin-bottom: 20px;
}

.mode-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 18px;
}

.references-card {
  margin-top: 18px;
  border-radius: 20px;
  padding: 18px;
  background: rgba(255, 255, 255, 0.45);
  border: 1px solid rgba(22, 33, 43, 0.08);
}

.references-head {
  display: flex;
  justify-content: space-between;
  gap: 16px;
  align-items: end;
  margin-bottom: 14px;
}

.references-list {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 10px 14px;
}

.references-list a {
  color: var(--text);
  text-decoration: none;
  padding: 10px 12px;
  border-radius: 12px;
  background: rgba(22, 33, 43, 0.03);
  border: 1px solid rgba(22, 33, 43, 0.08);
  line-height: 1.4;
}

.references-list a:hover {
  border-color: rgba(19, 91, 87, 0.28);
  background: rgba(19, 91, 87, 0.06);
}

body.theme-dark .references-card {
  background: rgba(255, 255, 255, 0.04);
  border-color: rgba(255, 255, 255, 0.08);
}

body.theme-dark .references-list a {
  background: rgba(255, 255, 255, 0.03);
  border-color: rgba(255, 255, 255, 0.08);
}

body.theme-dark .references-list a:hover {
  background: rgba(107, 208, 194, 0.08);
  border-color: rgba(107, 208, 194, 0.22);
}

.mode-card {
  border-radius: 20px;
  padding: 20px;
  min-height: 280px;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  gap: 18px;
}

.mode-card-primary {
  background: linear-gradient(180deg, rgba(255, 250, 243, 0.98), rgba(241, 231, 216, 0.96));
  border-color: rgba(19, 91, 87, 0.22);
}

.exam-picker {
  display: grid;
  grid-template-columns: repeat(7, minmax(0, 1fr));
  gap: 8px;
}

.exam-pill {
  padding: 12px 0;
  border-radius: 14px;
  background: rgba(22, 33, 43, 0.03);
  border: 1px solid rgba(22, 33, 43, 0.08);
  color: var(--text);
  cursor: pointer;
  transition: transform 0.18s ease, border-color 0.18s ease, background 0.18s ease;
}

.exam-pill:hover, .exam-pill.is-active {
  transform: translateY(-1px);
  border-color: rgba(19, 91, 87, 0.38);
  background: rgba(19, 91, 87, 0.09);
}

.action-button {
  width: 100%;
  padding: 14px 16px;
  border-radius: 12px;
  background: #35504d;
  color: #fffefc;
  font-weight: 700;
  letter-spacing: 0.02em;
  cursor: pointer;
  transition: transform 0.18s ease, filter 0.18s ease;
}

.action-button:hover {
  transform: translateY(-1px);
  filter: brightness(1.04);
}

.action-button.secondary {
  background: rgba(22, 33, 43, 0.03);
  color: var(--text);
  border: 1px solid rgba(19, 91, 87, 0.22);
}

body.theme-dark .hero-copy,
body.theme-dark .mode-card,
body.theme-dark .panel,
body.theme-dark .question-card,
body.theme-dark .rail,
body.theme-dark .stat-card,
body.theme-dark .results-summary,
body.theme-dark .results-side,
body.theme-dark .review-item {
  background: linear-gradient(180deg, rgba(10, 18, 24, 0.94), rgba(13, 23, 32, 0.92));
  border-color: rgba(255, 255, 255, 0.1);
}

body.theme-dark .mode-card-primary {
  background: linear-gradient(180deg, rgba(12, 24, 27, 0.96), rgba(8, 15, 20, 0.94));
  border-color: rgba(107, 208, 194, 0.2);
}

body.theme-dark .pill,
body.theme-dark .meta-chip,
body.theme-dark .theme-toggle,
body.theme-dark .ghost-button,
body.theme-dark .summary-mini,
body.theme-dark .review-option {
  background: rgba(255, 255, 255, 0.04);
  border-color: rgba(255, 255, 255, 0.08);
}

body.theme-dark .ghost-button.primary,
body.theme-dark .action-button.secondary {
  background: rgba(107, 208, 194, 0.1);
  border-color: rgba(107, 208, 194, 0.22);
}

body.theme-dark .action-button {
  background: linear-gradient(135deg, #6bd0c2, #2a7a71);
  color: #071015;
}

body.theme-dark .option {
  background: rgba(255, 255, 255, 0.03);
  border-color: rgba(255, 255, 255, 0.08);
}

body.theme-dark .option.is-selected,
body.theme-dark .exam-pill:hover,
body.theme-dark .exam-pill.is-active,
body.theme-dark .rail-button.is-current {
  background: rgba(107, 208, 194, 0.12);
  border-color: rgba(107, 208, 194, 0.28);
}

body.theme-dark .option-letter {
  background: rgba(107, 208, 194, 0.14);
  color: #90e4d8;
}

body.theme-dark .feedback {
  background: rgba(107, 208, 194, 0.08);
  border-color: rgba(107, 208, 194, 0.18);
}

.hidden { display: none !important; }

.toolbar-stats {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  justify-content: flex-end;
  text-align: right;
}

.pill {
  padding: 7px 11px;
  border-radius: 999px;
  background: rgba(22, 33, 43, 0.04);
  border: 1px solid rgba(22, 33, 43, 0.08);
  color: var(--text);
  font-size: 0.82rem;
}

.play-layout {
  display: grid;
  grid-template-columns: 210px minmax(0, 1fr);
  gap: 18px;
}

.play-layout.practice-mode {
  grid-template-columns: minmax(0, 1fr);
  width: min(100%, 980px);
  margin: 0 auto;
}

.play-layout.practice-mode .question-card {
  width: 100%;
  justify-self: center;
}

.rail {
  border-radius: 22px;
  padding: 14px;
  align-self: start;
  position: sticky;
  top: 20px;
  max-height: calc(100vh - 40px);
  overflow: auto;
  display: grid;
  grid-template-columns: repeat(5, minmax(0, 1fr));
  gap: 8px;
}

.rail-button {
  aspect-ratio: 1;
  border-radius: 12px;
  background: rgba(22, 33, 43, 0.03);
  color: var(--text);
  border: 1px solid rgba(22, 33, 43, 0.08);
  cursor: pointer;
  font-size: 0.82rem;
}

.rail-button.is-current {
  background: rgba(19, 91, 87, 0.14);
  border-color: rgba(19, 91, 87, 0.4);
}

.rail-button.is-answered {
  background: rgba(155, 92, 55, 0.1);
  border-color: rgba(155, 92, 55, 0.26);
}

.rail-button.is-correct {
  background: rgba(32, 116, 79, 0.12);
  border-color: rgba(32, 116, 79, 0.3);
}

.rail-button.is-wrong {
  background: rgba(180, 35, 24, 0.12);
  border-color: rgba(180, 35, 24, 0.32);
}

.question-card {
  border-radius: 24px;
  padding: 22px;
}

.question-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: 14px;
}

.meta-chip {
  padding: 7px 11px;
  border-radius: 999px;
  background: rgba(22, 33, 43, 0.04);
  border: 1px solid rgba(22, 33, 43, 0.08);
  font-size: 0.8rem;
}

#questionText {
  max-width: 78ch;
  margin-bottom: 16px;
  line-height: 1.75;
}

.options-list {
  display: grid;
  gap: 10px;
  margin-bottom: 16px;
}

.option {
  border-radius: 14px;
  border: 1px solid rgba(22, 33, 43, 0.1);
  background: rgba(255, 255, 255, 0.55);
  padding: 12px 14px;
  display: flex;
  align-items: flex-start;
  gap: 12px;
  cursor: pointer;
  transition: transform 0.16s ease, border-color 0.16s ease, background 0.16s ease;
}

.option:hover {
  transform: translateY(-1px);
  border-color: rgba(19, 91, 87, 0.34);
}

.option input {
  margin-top: 3px;
}

.option-letter {
  flex: 0 0 auto;
  width: 28px;
  height: 28px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border-radius: 10px;
  background: rgba(19, 91, 87, 0.12);
  color: var(--accent-2);
  font-weight: 700;
}

.option-text {
  color: var(--text);
  line-height: 1.7;
}

.option.is-selected {
  border-color: rgba(19, 91, 87, 0.42);
  background: rgba(19, 91, 87, 0.08);
}

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

.ghost-button {
  padding: 12px 14px;
  border-radius: 12px;
  border: 1px solid rgba(22, 33, 43, 0.1);
  background: rgba(255, 255, 255, 0.4);
  color: var(--text);
  cursor: pointer;
}

.ghost-button.primary {
  background: rgba(19, 91, 87, 0.14);
  border-color: rgba(19, 91, 87, 0.28);
}

.ghost-button.warn {
  background: rgba(180, 35, 24, 0.08);
  border-color: rgba(180, 35, 24, 0.24);
}

.feedback {
  border-radius: 14px;
  padding: 14px;
  margin-bottom: 16px;
  border: 1px solid rgba(19, 91, 87, 0.2);
  background: rgba(19, 91, 87, 0.06);
}

.feedback.feedback-correct {
  border-color: rgba(32, 116, 79, 0.28);
  background: rgba(32, 116, 79, 0.1);
}

.feedback.feedback-incorrect {
  border-color: rgba(180, 35, 24, 0.26);
  background: rgba(180, 35, 24, 0.08);
}

body.theme-dark .feedback.feedback-correct {
  border-color: rgba(123, 215, 154, 0.3);
  background: rgba(123, 215, 154, 0.12);
}

body.theme-dark .feedback.feedback-incorrect {
  border-color: rgba(255, 143, 143, 0.3);
  background: rgba(255, 143, 143, 0.12);
}

.feedback strong {
  display: block;
  margin-bottom: 8px;
}

.results-head {
  display: grid;
  grid-template-columns: minmax(0, 1.2fr) minmax(260px, 0.8fr);
  gap: 16px;
  margin-bottom: 16px;
}

.results-summary, .results-side {
  border-radius: 20px;
  padding: 20px;
  background: linear-gradient(180deg, rgba(255, 250, 243, 0.96), rgba(247, 240, 230, 0.94));
  border: 1px solid var(--line);
}

.score-big {
  font-family: var(--serif);
  font-size: clamp(2.6rem, 6vw, 4.8rem);
  margin: 6px 0;
}

.summary-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 12px;
  margin-top: 18px;
}

.summary-mini {
  padding: 14px;
  border-radius: 16px;
  background: rgba(22, 33, 43, 0.03);
  border: 1px solid rgba(22, 33, 43, 0.08);
}

.summary-mini span {
  display: block;
  color: var(--muted);
  font-size: 0.78rem;
  margin-bottom: 6px;
}

.summary-mini strong {
  font-size: 1.35rem;
}

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

.review-item {
  border-radius: 16px;
  overflow: hidden;
  border: 1px solid rgba(22, 33, 43, 0.1);
  background: rgba(255, 255, 255, 0.55);
}

.review-item summary {
  cursor: pointer;
  list-style: none;
  padding: 14px 16px;
  display: flex;
  justify-content: space-between;
  gap: 14px;
  align-items: flex-start;
}

.review-item summary > div {
  flex: 1;
}

.review-item summary .muted {
  display: block;
  margin-top: 6px;
}

.review-item summary::-webkit-details-marker {
  display: none;
}

.review-status {
  padding: 6px 10px;
  border-radius: 999px;
  font-size: 0.8rem;
}

.review-status.good {
  background: rgba(126, 240, 165, 0.12);
  color: var(--good);
}

.review-status.bad {
  background: rgba(255, 125, 125, 0.12);
  color: var(--bad);
}

.review-body {
  padding: 0 16px 16px;
  color: var(--muted);
  line-height: 1.75;
}

.review-body .answer-line {
  color: var(--text);
  margin: 10px 0 0;
}

.review-question-block {
  margin-top: 16px;
}

.review-question-block h4 {
  margin: 0 0 8px;
  font-family: var(--serif);
  font-size: 1rem;
}

.review-question-text,
.review-explanation {
  margin: 0;
  color: var(--text);
  line-height: 1.7;
}

.review-options {
  display: grid;
  gap: 10px;
}

.review-option {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 10px;
  padding: 12px 14px;
  border-radius: 14px;
  background: rgba(22, 33, 43, 0.03);
  border: 1px solid rgba(22, 33, 43, 0.08);
}

.timer {
  font-variant-numeric: tabular-nums;
}

.ambient {
  position: fixed;
  inset: auto;
  pointer-events: none;
  filter: blur(40px);
  opacity: 0.7;
}

.ambient-a {
  top: -120px;
  left: -80px;
  width: 380px;
  height: 380px;
  background: rgba(19, 91, 87, 0.12);
}

.ambient-b {
  right: -140px;
  top: 120px;
  width: 420px;
  height: 420px;
  background: rgba(155, 92, 55, 0.1);
}

.grain {
  position: fixed;
  inset: 0;
  pointer-events: none;
  opacity: 0.05;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='180' height='180' viewBox='0 0 180 180'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.8' numOctaves='2' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='180' height='180' filter='url(%23n)' opacity='0.6'/%3E%3C/svg%3E");
}

.confirm-dialog {
  position: fixed;
  inset: 0;
  z-index: 50;
  display: grid;
  place-items: center;
}

.confirm-backdrop {
  position: absolute;
  inset: 0;
  background: rgba(6, 10, 14, 0.42);
  backdrop-filter: blur(8px);
}

.confirm-panel {
  position: relative;
  z-index: 1;
  width: min(520px, calc(100vw - 28px));
  padding: 24px;
  border-radius: 24px;
  background: linear-gradient(180deg, rgba(255, 250, 243, 0.98), rgba(247, 240, 230, 0.96));
  border: 1px solid var(--line);
  box-shadow: var(--shadow);
}

.confirm-message {
  margin: 10px 0 0;
  line-height: 1.65;
  color: var(--muted);
}

.confirm-actions {
  display: flex;
  gap: 12px;
  justify-content: flex-end;
  margin-top: 22px;
}

body.theme-dark .confirm-panel {
  background: linear-gradient(180deg, rgba(10, 18, 24, 0.98), rgba(13, 23, 32, 0.96));
}

@media (max-width: 1080px) {
  .hero, .results-head, .mode-grid, .play-layout {
    grid-template-columns: 1fr;
  }

  .rail {
    position: static;
    max-height: none;
  }

  .toolbar, .panel-head {
    align-items: start;
    flex-direction: column;
  }
}

@media (max-width: 720px) {
  body {
    padding-top: 72px;
  }

  .site-alert {
    padding: 10px 14px;
    align-items: flex-start;
    gap: 10px;
  }

  .site-alert-text {
    font-size: 0.8rem;
  }

  .shell {
    width: min(100vw - 18px, 1360px);
    padding-top: 12px;
  }

  .panel, .hero-copy, .question-card, .mode-card, .results-summary, .results-side {
    border-radius: 20px;
  }

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

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

  .references-head,
  .references-list {
    grid-template-columns: 1fr;
    display: grid;
  }

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

  .confirm-actions {
    flex-direction: column;
  }
}