:root {
  --bg: #edf4ff;
  --panel: rgba(255, 255, 255, 0.92);
  --panel-strong: #ffffff;
  --ink: #10233f;
  --muted: #526d92;
  --line: #cad9ef;
  --primary: #1d5fd1;
  --primary-strong: #143d8f;
  --danger: #b03f3f;
  --success: #15803d;
  --shadow: 0 18px 48px rgba(16, 35, 63, 0.12);
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  min-height: 100vh;
  font-family: "IBM Plex Sans", "Segoe UI", sans-serif;
  color: var(--ink);
  background:
    radial-gradient(circle at top left, rgba(29, 95, 209, 0.18), transparent 28%),
    radial-gradient(circle at top right, rgba(90, 167, 255, 0.16), transparent 22%),
    linear-gradient(180deg, #f5f9ff 0%, #e7f0ff 100%);
}

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

.shell {
  width: min(1440px, calc(100vw - 40px));
  margin: 0 auto;
  padding: 24px 0 40px;
}

.card {
  background: var(--panel);
  border: 1px solid rgba(255, 255, 255, 0.95);
  border-radius: 28px;
  box-shadow: var(--shadow);
  backdrop-filter: blur(16px);
}

.btn,
.nav-link {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  border-radius: 18px;
  border: 1px solid transparent;
  padding: 14px 22px;
  font: inherit;
  font-weight: 700;
  cursor: pointer;
  transition: transform 140ms ease, background 140ms ease, border-color 140ms ease;
}

.btn:hover,
.nav-link:hover {
  transform: translateY(-1px);
}

.btn-primary {
  background: var(--primary);
  color: #fff;
}

.btn-primary:hover {
  background: var(--primary-strong);
}

.btn-secondary,
.nav-link {
  background: rgba(255, 255, 255, 0.78);
  border-color: var(--line);
  color: var(--ink);
}

.btn-danger {
  background: var(--danger);
  color: #fff;
}

.btn-block {
  width: 100%;
}

.eyebrow {
  margin: 0 0 10px;
  color: var(--primary);
  font-size: 0.78rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  font-weight: 700;
}

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

.hero {
  min-height: 100vh;
  display: grid;
  place-items: center;
  padding: 24px;
  position: relative;
}

.purchase-action {
  position: fixed;
  top: 24px;
  right: 24px;
  z-index: 5;
}

.purchase-action .btn {
  border-color: rgba(29, 95, 209, 0.3);
  background: rgba(255, 255, 255, 0.88);
  box-shadow: 0 12px 30px rgba(16, 35, 63, 0.12);
}

.purchase-action span {
  color: var(--primary);
}

.hero-card {
  width: min(760px, 100%);
  padding: 56px 44px;
  text-align: center;
}

.hero-icon {
  width: 112px;
  height: 112px;
  margin: 0 auto 26px;
  border-radius: 28px;
  display: grid;
  place-items: center;
  background: linear-gradient(135deg, #1d5fd1, #5aa7ff);
  color: #fff;
  font-size: 3rem;
  box-shadow: 0 24px 60px rgba(29, 95, 209, 0.3);
}

.hero h1,
.topbar h1,
.results-card h1 {
  margin: 0;
  line-height: 1.04;
}

.hero h1 {
  font-size: clamp(2.4rem, 5vw, 4.4rem);
}

.hero-copy {
  max-width: 600px;
  margin: 18px auto 0;
  color: var(--muted);
  font-size: 1.05rem;
  line-height: 1.55;
}

.hero-actions,
.topbar-actions,
.results-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  align-items: center;
  justify-content: center;
}

.sample-account-form {
  display: grid;
  gap: 10px;
  max-width: 560px;
  margin: 30px auto 0;
  text-align: left;
}

.sample-account-form label {
  color: var(--muted);
  font-size: 0.82rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
}

.email-entry {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  gap: 10px;
}

.email-entry input,
.access-grid input {
  width: 100%;
  min-height: 52px;
  border: 1px solid var(--line);
  border-radius: 18px;
  padding: 0 16px;
  font: inherit;
  color: var(--ink);
  background: rgba(255, 255, 255, 0.9);
}

.access-gate-form {
  margin-top: 26px;
  padding-top: 24px;
  border-top: 1px solid var(--line);
}

.access-gate-form h2 {
  margin: 0;
  font-size: 1.35rem;
  line-height: 1.2;
}

.payment-link-row {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 10px;
}

.payment-link-row .btn {
  min-height: 48px;
  padding-inline: 14px;
}

.access-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1fr) auto;
  gap: 10px;
}

.access-code-grid {
  grid-template-columns: minmax(0, 1fr) auto;
}

.form-status[data-tone="success"] {
  color: var(--success);
}

.access-expiration-panel {
  display: grid;
  gap: 4px;
  padding: 12px 14px;
  border: 1px solid rgba(21, 128, 61, 0.22);
  border-radius: 16px;
  background: rgba(21, 128, 61, 0.08);
  color: var(--muted);
  font-size: 0.92rem;
}

.access-expiration-panel strong {
  color: var(--success);
}

.form-status {
  min-height: 20px;
  margin: 0;
  color: var(--danger);
  font-size: 0.92rem;
}

.form-helper {
  margin: 0;
  color: var(--muted);
  font-size: 0.95rem;
}

.book-setup {
  margin-top: 30px;
  padding-top: 26px;
  border-top: 1px solid var(--line);
  text-align: left;
}

.book-setup-header {
  display: grid;
  gap: 8px;
  margin-bottom: 18px;
}

.book-setup-header h2 {
  margin: 0;
  font-size: 1.35rem;
  line-height: 1.2;
}

.book-setup-list {
  display: grid;
  gap: 10px;
}

.book-setup-row {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  gap: 12px;
  align-items: center;
  padding: 12px 14px;
  border: 1px solid var(--line);
  border-radius: 18px;
  background: rgba(255, 255, 255, 0.72);
}

.book-link-status {
  display: block;
  margin-top: 3px;
  color: var(--muted);
  font-size: 0.88rem;
}

.online-reference-note {
  margin-top: 14px;
  padding: 14px 16px;
  border-radius: 16px;
  background: #edf4ff;
  color: var(--muted);
  line-height: 1.5;
}

.online-reference-note strong {
  color: var(--ink);
}

.topbar {
  display: flex;
  justify-content: space-between;
  gap: 20px;
  align-items: center;
  margin-bottom: 20px;
  padding: 20px 24px;
}

.topbar h1 {
  font-size: 2rem;
}

.question-source-label {
  margin: 8px 0 0;
  color: var(--muted);
  font-size: 0.9rem;
  font-weight: 600;
}

.question-source-label[data-source-type="google-sheet"] {
  color: var(--success);
}

.timer-chip {
  display: flex;
  align-items: center;
  gap: 18px;
  border-radius: 18px;
  padding: 12px 18px;
  background: rgba(255, 255, 255, 0.74);
  border: 1px solid rgba(255, 255, 255, 0.88);
}

.timer-value {
  font-family: "IBM Plex Mono", monospace;
  font-size: 2rem;
  font-weight: 700;
  color: var(--danger);
}

.exam-layout {
  display: grid;
  grid-template-columns: 280px minmax(420px, 1fr);
  gap: 20px;
  min-height: calc(100vh - 152px);
}

.sidebar,
.exam-panel,
.pdf-panel {
  min-height: 0;
}

.sidebar {
  padding: 22px;
  overflow: auto;
}

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

.reference-placeholder-list,
.reference-group {
  display: grid;
  gap: 12px;
}

.reference-group + .reference-group {
  margin-top: 18px;
}

.reference-group-title {
  color: var(--muted);
  font-size: 0.78rem;
  font-weight: 800;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

.book-item {
  width: 100%;
  padding: 14px 16px;
  border-radius: 18px;
  border: 1px solid var(--line);
  background: rgba(255, 255, 255, 0.78);
  text-align: left;
}

.reference-book,
.online-reference {
  color: var(--ink);
  font-weight: 700;
  cursor: pointer;
}

.reference-book:hover,
.online-reference:hover {
  border-color: var(--primary);
  background: #f7fbff;
}

.online-reference {
  background: #edf4ff;
}

.book-title {
  display: block;
  font-weight: 700;
}

.book-meta {
  display: block;
  margin-top: 4px;
  font-size: 0.85rem;
  color: var(--muted);
}

.exam-panel {
  padding: 30px;
}

.pdf-panel {
  display: grid;
  grid-template-rows: auto auto minmax(0, 1fr) auto;
  gap: 14px;
  padding: 22px;
}

.pdf-panel-header {
  display: flex;
  justify-content: space-between;
  gap: 12px;
  align-items: start;
}

.pdf-panel h2 {
  margin: 0;
  font-size: 1.25rem;
  line-height: 1.2;
}

.pdf-upload {
  display: grid;
  gap: 8px;
  padding: 12px 14px;
  border: 1px solid var(--line);
  border-radius: 18px;
  background: rgba(255, 255, 255, 0.72);
  color: var(--muted);
  font-size: 0.9rem;
  font-weight: 700;
}

.pdf-upload input {
  width: 100%;
  color: var(--ink);
  font: inherit;
}

.pdf-open-link {
  width: fit-content;
  color: var(--primary);
  font-size: 0.92rem;
  font-weight: 800;
  text-decoration: underline;
}

.pdf-open-link[hidden] {
  display: none;
}

.pdf-js-viewer {
  min-height: 0;
  overflow: auto;
  border: 1px solid var(--line);
  border-radius: 18px;
  background: #f8fbff;
}

.pdf-js-viewer[hidden] {
  display: none;
}

.pdf-js-toolbar {
  position: sticky;
  top: 0;
  z-index: 1;
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  align-items: center;
  justify-content: space-between;
  padding: 10px;
  border-bottom: 1px solid var(--line);
  background: rgba(255, 255, 255, 0.96);
}

.pdf-js-toolbar .btn {
  padding: 10px 12px;
  border-radius: 14px;
  font-size: 0.85rem;
}

#pdf-page-status {
  color: var(--muted);
  font-size: 0.9rem;
  font-weight: 800;
}

#pdf-canvas {
  display: block;
  width: 100%;
  height: auto;
  background: #fff;
}

#pdf-viewer {
  width: 100%;
  min-height: 560px;
  height: 100%;
  border: 1px solid var(--line);
  border-radius: 18px;
  background: #fff;
}

.pdf-status {
  margin: 0;
  color: var(--muted);
  font-size: 0.9rem;
  line-height: 1.4;
}

.viewer-shell {
  width: min(1100px, calc(100vw - 32px));
  margin: 0 auto;
  padding: 20px 0 32px;
}

.standalone-pdf-panel {
  display: grid;
  gap: 12px;
  min-height: calc(100vh - 150px);
  padding: 18px;
}

.standalone-pdf-panel .pdf-js-viewer {
  min-height: calc(100vh - 220px);
}

.question-meta {
  display: flex;
  justify-content: space-between;
  gap: 12px;
  align-items: baseline;
  margin-bottom: 24px;
}

.submit-warning {
  display: grid;
  gap: 8px;
  margin-bottom: 18px;
  padding: 16px 18px;
  border: 1px solid #f0b4b4;
  border-radius: 18px;
  background: #fff1f1;
  color: #7f1d1d;
}

.submit-warning[hidden] {
  display: none;
}

.submit-warning a {
  width: fit-content;
  font-weight: 800;
  color: var(--danger);
  text-decoration: underline;
}

.question-card {
  padding: 32px;
  border-radius: 24px;
  border: 1px solid var(--line);
  background: rgba(255, 255, 255, 0.84);
}

.question-card p {
  margin-top: 0;
}

.answer-list {
  display: grid;
  gap: 14px;
}

.answer-option {
  display: flex;
  gap: 14px;
  align-items: center;
  padding: 16px 18px;
  border-radius: 18px;
  border: 1px solid transparent;
  transition: border-color 140ms ease, background 140ms ease;
}

.answer-option:hover {
  border-color: #b4caf1;
  background: #f7fbff;
}

.answer-option input {
  width: 18px;
  height: 18px;
  accent-color: var(--primary);
}

.nav-row {
  display: flex;
  justify-content: space-between;
  gap: 12px;
  margin-top: 20px;
}

.review-panel {
  margin-top: 24px;
  padding-top: 22px;
  border-top: 1px solid var(--line);
}

.review-panel-header {
  display: flex;
  justify-content: space-between;
  gap: 12px;
  align-items: end;
  margin-bottom: 14px;
}

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

.review-list-page {
  display: grid;
  gap: 16px;
  max-height: 70vh;
  overflow-y: auto;
  padding-right: 6px;
}

.review-question-card {
  padding: 24px;
  border-radius: 22px;
  border: 1px solid var(--line);
  background: rgba(255, 255, 255, 0.82);
}

.review-question-card h3 {
  margin: 0 0 10px;
  font-size: 1.15rem;
}

.review-question-card .answer-list {
  margin-top: 18px;
}

.review-empty {
  padding: 28px;
  border-radius: 22px;
  border: 1px dashed var(--line);
  background: rgba(255, 255, 255, 0.62);
  text-align: center;
}

.review-tile {
  min-height: 44px;
  border-radius: 14px;
  border: 1px solid var(--line);
  background: #e8eef9;
  color: var(--muted);
  font-weight: 700;
}

.review-tile.answered {
  background: #fff;
  color: var(--ink);
}

.review-tile.review {
  background: #111827;
  border-color: #111827;
  color: #fff;
}

.review-tile.current {
  box-shadow: inset 0 0 0 3px var(--primary);
}

.results-wrap {
  min-height: 100vh;
  display: grid;
  place-items: center;
  padding: 24px;
}

.results-detail-wrap {
  width: min(1100px, calc(100vw - 32px));
  margin: 0 auto;
  place-items: stretch;
  align-content: start;
  gap: 20px;
}

.results-card {
  width: min(620px, 100%);
  justify-self: center;
  padding: 44px;
  text-align: center;
}

.results-review-panel {
  padding: 28px;
}

.results-review-panel h2 {
  margin: 0;
}

.answer-review-list {
  display: grid;
  gap: 16px;
}

.answer-review-card {
  padding: 22px;
  border: 1px solid var(--line);
  border-left: 6px solid var(--danger);
  border-radius: 20px;
  background: rgba(255, 255, 255, 0.82);
}

.answer-review-card.correct {
  border-left-color: var(--success);
}

.answer-review-card h3 {
  margin: 14px 0 16px;
  line-height: 1.35;
}

.answer-review-topline {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  align-items: center;
  justify-content: space-between;
}

.badge {
  border-radius: 999px;
  padding: 6px 10px;
  font-size: 0.85rem;
  font-weight: 700;
  background: #edf3fd;
  color: var(--muted);
}

.badge.good {
  background: #e4f7e9;
  color: var(--success);
}

.badge.warn {
  background: #ffe8e8;
  color: var(--danger);
}

.answer-review-answers,
.answer-reference,
.answer-explanation {
  display: grid;
  gap: 8px;
  margin-top: 12px;
  padding-top: 12px;
  border-top: 1px solid var(--line);
}

.answer-review-answers p {
  margin: 0;
}

.answer-reference,
.answer-explanation {
  color: var(--muted);
  line-height: 1.55;
}

.score-circle {
  width: 192px;
  height: 192px;
  margin: 0 auto 28px;
  border-radius: 50%;
  border: 10px solid #bfe5c8;
  display: grid;
  place-items: center;
}

.score-main {
  font-size: 4rem;
  font-weight: 800;
}

.score-sub {
  color: var(--muted);
  font-size: 0.95rem;
}

@media (max-width: 1100px) {
  .exam-layout {
    grid-template-columns: 1fr;
  }

  #pdf-viewer {
    min-height: 70vh;
  }
}

@media (max-width: 720px) {
  .shell {
    width: min(100vw - 24px, 100%);
    padding-top: 12px;
  }

  .hero-card,
  .exam-panel,
  .pdf-panel,
  .results-card {
    padding: 28px 20px;
  }

  .topbar,
  .question-meta,
  .nav-row,
  .email-entry,
  .payment-link-row,
  .access-grid,
  .book-setup-row {
    grid-template-columns: 1fr;
    display: grid;
  }

  .topbar-actions,
  .results-actions {
    justify-content: stretch;
  }

  .topbar-actions > *,
  .results-actions > * {
    width: 100%;
  }

  .purchase-action {
    position: static;
    width: 100%;
    margin-bottom: 14px;
  }

  .purchase-action .btn {
    width: 100%;
  }

  .pdf-toolbar,
  .pdf-search-form {
    flex-direction: column;
    align-items: stretch;
  }


  .pdf-search-input {
    width: 100%;
  }

  .review-grid {
    grid-template-columns: repeat(5, minmax(0, 1fr));
  }
}