:root {
  color-scheme: light;
  --ink: #18212a;
  --muted: #566371;
  --line: #cbd5df;
  --paper: #f4f7f6;
  --panel: #ffffff;
  --green: #1d7f5f;
  --teal: #107481;
  --red: #b8423a;
  --gold: #c69320;
  --blue: #2457a6;
}

* {
  box-sizing: border-box;
}

[hidden] {
  display: none !important;
}

body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: Arial, Helvetica, sans-serif;
}

button {
  font: inherit;
}

.app {
  min-height: 100vh;
}

.topbar {
  display: flex;
  justify-content: space-between;
  gap: 24px;
  padding: 24px clamp(16px, 4vw, 48px) 16px;
  background: #ffffff;
  border-bottom: 1px solid var(--line);
}

.topbar h1,
.progress-panel h2,
.question-panel h2,
.subject-section h2,
.unit-heading h3,
.topic-card h4,
.unit-card strong,
.unit-page-heading h3,
.unit-topic-card strong {
  margin: 0;
  line-height: 1.08;
}

.topbar h1 {
  font-size: clamp(2rem, 4vw, 4rem);
}

.summary {
  max-width: 560px;
  margin: 8px 0 0;
  color: var(--muted);
  line-height: 1.45;
}

.eyebrow {
  margin: 0 0 8px;
  color: var(--teal);
  font-size: 0.78rem;
  font-weight: 800;
  letter-spacing: 0;
  text-transform: uppercase;
}

.setup,
.review,
.topic-review {
  display: grid;
  gap: 18px;
  padding: 24px clamp(16px, 4vw, 48px) 36px;
}

.setup,
.review {
  grid-template-columns: minmax(0, 1fr) 360px;
}

.setup {
  grid-template-columns: minmax(0, 0.78fr) minmax(420px, 1.22fr);
}

.setup.subject-only {
  display: block;
}

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

.subject-list {
  display: grid;
  gap: 18px;
}

.subject-section,
.subject-card,
.unit-card,
.unit-topic-card,
.topic-card,
.topic-review-panel,
.question-panel,
.progress-panel {
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: 8px;
}

.subject-section {
  padding: 18px;
}

.subject-nav {
  margin-bottom: 18px;
}

.subject-card {
  width: 100%;
  min-height: 116px;
  padding: 22px;
  text-align: left;
  cursor: pointer;
  transition: border-color 160ms ease, box-shadow 160ms ease, transform 160ms ease;
}

.subject-card h2 {
  margin: 0;
  font-size: clamp(1.5rem, 3vw, 2.4rem);
  line-height: 1.08;
}

.subject-card:hover {
  border-color: var(--green);
  box-shadow: 0 0 0 4px rgba(29, 127, 95, 0.14);
  transform: translateY(-2px);
}

.subject-section h2 {
  font-size: clamp(1.5rem, 3vw, 2.2rem);
}

.unit-list {
  display: grid;
  gap: 10px;
  margin-top: 18px;
}

.unit-card {
  display: grid;
  grid-template-columns: 92px minmax(0, 1fr);
  align-items: center;
  gap: 16px;
  min-height: 68px;
  width: 100%;
  padding: 16px 18px;
  text-align: left;
  cursor: pointer;
  transition: border-color 160ms ease, box-shadow 160ms ease, transform 160ms ease;
}

.unit-card:hover,
.unit-topic-card:hover,
.unit-topic-card.selected {
  border-color: var(--green);
  box-shadow: 0 0 0 4px rgba(29, 127, 95, 0.14);
  transform: translateY(-2px);
}

.unit-card span {
  color: var(--muted);
  font-weight: 800;
  text-transform: uppercase;
}

.unit-card strong {
  font-size: clamp(1.05rem, 2vw, 1.45rem);
}

.unit-page-heading {
  margin-top: 18px;
  padding-top: 16px;
  border-top: 1px solid var(--line);
}

.unit-page-heading h3 {
  font-size: clamp(1.35rem, 3vw, 2rem);
}

.coming-soon {
  margin: 18px 0 0;
  padding: 16px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #f7faf9;
  color: var(--muted);
  font-weight: 800;
}

.unit-topic-list {
  display: grid;
  gap: 10px;
  margin-top: 18px;
}

.unit-topic-card {
  display: grid;
  grid-template-columns: 72px minmax(0, 1fr) auto;
  align-items: center;
  gap: 14px;
  min-height: 64px;
  padding: 14px 16px;
  text-align: left;
  cursor: pointer;
  transition: border-color 160ms ease, box-shadow 160ms ease, transform 160ms ease;
}

.unit-topic-card span {
  color: var(--teal);
  font-weight: 800;
}

.unit-topic-card strong {
  font-size: 1.05rem;
}

.unit-topic-card em {
  color: var(--muted);
  font-style: normal;
  font-weight: 800;
}

.unit-block {
  margin-top: 18px;
  padding-top: 16px;
  border-top: 1px solid var(--line);
}

.unit-heading {
  max-width: 720px;
}

.unit-heading h3 {
  font-size: 1.15rem;
}

.unit-heading p,
.topic-card p {
  color: var(--muted);
  line-height: 1.45;
}

.topic-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 12px;
  margin-top: 12px;
}

.topic-card {
  min-height: 168px;
  padding: 18px;
  text-align: left;
  cursor: pointer;
  transition: border-color 160ms ease, box-shadow 160ms ease, transform 160ms ease;
}

.topic-card:hover,
.topic-card.selected {
  border-color: var(--green);
  box-shadow: 0 0 0 4px rgba(29, 127, 95, 0.14);
  transform: translateY(-2px);
}

.progress-panel p {
  color: var(--muted);
  line-height: 1.45;
}

.topic-card h4 {
  font-size: 1.1rem;
}

.tag-row {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 16px;
}

.tag {
  padding: 6px 8px;
  border-radius: 8px;
  background: #e9f4f1;
  color: #1b5d4a;
  font-size: 0.86rem;
  font-weight: 800;
}

.question-panel,
.topic-review-panel,
.progress-panel {
  padding: 18px;
}

.topic-review-panel h2 {
  margin: 0;
  font-size: clamp(1.6rem, 3vw, 2.6rem);
  line-height: 1.08;
}

.topic-review-content {
  display: grid;
  gap: 4px;
  margin-top: 18px;
}

.progress-panel .btn {
  margin: 4px 8px 4px 0;
}

.metadata-section {
  margin: 16px 0;
}

.metadata-section h3 {
  margin: 0 0 8px;
  color: var(--teal);
  font-size: 0.78rem;
  font-weight: 800;
  letter-spacing: 0;
  text-transform: uppercase;
}

.metadata-section ul {
  display: grid;
  gap: 8px;
  margin: 0;
  padding-left: 18px;
}

.metadata-section li {
  color: var(--muted);
  line-height: 1.35;
}

.summary-block,
.summary-one-sentence {
  margin-top: 14px;
}

.summary-block h4,
.summary-one-sentence h4 {
  margin: 0 0 8px;
  color: var(--ink);
  font-size: 1rem;
  line-height: 1.2;
}

.summary-one-sentence p {
  margin: 0;
  color: var(--muted);
  line-height: 1.4;
}

.env-review-sheet {
  display: grid;
  gap: 14px;
  margin: 0;
}

.env-review-hero {
  display: grid;
  gap: 8px;
  padding: 16px;
  border: 1px solid var(--line);
  border-radius: 10px;
  background: linear-gradient(140deg, #e5f6ed 0%, #eef6ff 100%);
}

.env-review-hero h3 {
  margin: 0;
  font-size: clamp(1.2rem, 2.6vw, 1.9rem);
  line-height: 1.12;
}

.env-review-hero p {
  margin: 0;
  color: var(--muted);
  line-height: 1.4;
}

.env-review-gallery {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
  gap: 10px;
}

.env-review-figure {
  margin: 0;
  border: 1px solid var(--line);
  border-radius: 10px;
  overflow: hidden;
  background: #ffffff;
}

.env-review-figure img {
  display: block;
  width: 100%;
  aspect-ratio: 16 / 10;
  object-fit: cover;
  background: #edf2f2;
}

.env-review-figure figcaption {
  display: grid;
  gap: 4px;
  padding: 10px;
  color: var(--muted);
  font-size: 0.82rem;
  line-height: 1.35;
}

.env-review-figure figcaption strong {
  color: var(--ink);
}

.env-review-figure a {
  color: var(--blue);
  font-weight: 800;
  text-decoration: none;
}

.env-review-figure a:hover {
  text-decoration: underline;
}

.env-review-card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 10px;
}

.env-review-card {
  display: grid;
  gap: 10px;
  padding: 14px;
  border: 1px solid var(--line);
  border-radius: 10px;
  background: #ffffff;
}

.env-review-card h4 {
  margin: 0;
  font-size: 1.03rem;
  line-height: 1.25;
}

.env-review-card ul {
  display: grid;
  gap: 7px;
  margin: 0;
  padding-left: 18px;
}

.env-review-card li {
  color: var(--muted);
  line-height: 1.35;
}

.env-review-callout {
  margin: 0;
  padding: 10px;
  border-left: 4px solid var(--green);
  border-radius: 7px;
  background: #f2faf6;
  color: #245448;
  line-height: 1.35;
}

.env-review-compare {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 8px;
}

.env-review-compare-card {
  display: grid;
  gap: 8px;
  padding: 10px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #f8fbfc;
}

.env-review-compare-card h5 {
  margin: 0;
  font-size: 0.9rem;
  line-height: 1.2;
}

.env-review-compare-card ul {
  display: grid;
  gap: 6px;
  margin: 0;
  padding-left: 16px;
}

.env-review-keytakeaways {
  display: grid;
  gap: 10px;
  padding: 14px;
  border: 1px solid var(--line);
  border-radius: 10px;
  background: linear-gradient(180deg, #ffffff 0%, #f6faf9 100%);
}

.env-review-keytakeaways h4 {
  margin: 0;
  font-size: 1rem;
  line-height: 1.25;
}

.env-review-keytakeaways ul {
  display: grid;
  gap: 7px;
  margin: 0;
  padding-left: 18px;
}

.env-review-keytakeaways li {
  color: var(--muted);
  line-height: 1.35;
}

.question-meta,
.button-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 10px;
}

.score {
  margin: 0;
  color: var(--blue);
  font-weight: 800;
}

.question-panel h2 {
  margin-top: 8px;
  font-size: clamp(1.45rem, 3vw, 2.35rem);
}

.answers {
  display: grid;
  gap: 10px;
  margin-top: 18px;
}

.short-answer-hint {
  margin: 0;
  color: var(--muted);
  line-height: 1.4;
}

.short-answer-input {
  width: 100%;
  min-height: 140px;
  padding: 12px;
  border: 1px solid var(--line);
  border-radius: 8px;
  color: var(--ink);
  font: inherit;
  line-height: 1.35;
  resize: vertical;
}

.short-rubric {
  display: grid;
  gap: 8px;
  padding: 12px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #f7faf9;
}

.short-rubric h3 {
  margin: 0;
  color: var(--teal);
  font-size: 0.95rem;
  line-height: 1.2;
}

.short-rubric ul {
  display: grid;
  gap: 6px;
  margin: 0;
  padding-left: 18px;
}

.short-rubric li {
  color: var(--muted);
  line-height: 1.35;
}

.short-assess-row {
  justify-content: flex-start;
}

.btn,
.answer {
  min-height: 42px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #ffffff;
  color: var(--ink);
  cursor: pointer;
  font-weight: 800;
}

.btn {
  padding: 10px 14px;
}

.answer {
  padding: 13px;
  text-align: left;
}

.btn.primary,
.answer:hover {
  background: var(--green);
  border-color: var(--green);
  color: #ffffff;
}

.answer.correct {
  border-color: var(--green);
  background: #e4f5ef;
  color: var(--ink);
}

.answer.incorrect {
  border-color: var(--red);
  background: #ffe9e7;
  color: var(--ink);
}

.answer:disabled {
  cursor: default;
}

.feedback {
  min-height: 54px;
  color: var(--muted);
  line-height: 1.45;
}

.feedback.good {
  color: var(--green);
  font-weight: 800;
}

.feedback.warn {
  color: var(--red);
  font-weight: 800;
}

.button-row {
  justify-content: flex-start;
  flex-wrap: wrap;
  margin-top: 14px;
}

.question-count-dialog {
  width: min(480px, calc(100vw - 32px));
  padding: 0;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #ffffff;
  color: var(--ink);
  box-shadow: 0 24px 60px rgba(24, 33, 42, 0.22);
}

.question-count-dialog::backdrop {
  background: rgba(24, 33, 42, 0.42);
}

.question-count-form {
  display: grid;
  gap: 18px;
  padding: 20px;
}

.results-download-dialog {
  width: min(440px, calc(100vw - 32px));
}

.results-download-content {
  gap: 14px;
}

.results-download-actions .btn {
  min-width: 120px;
}

.question-count-form h2 {
  margin: 0;
  font-size: 1.6rem;
  line-height: 1.1;
}

.question-count-summary {
  margin: 8px 0 0;
  color: var(--muted);
  line-height: 1.4;
}

.question-count-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 12px;
}

.count-field {
  display: grid;
  gap: 8px;
  color: var(--muted);
  font-weight: 800;
}

.count-field input {
  width: 100%;
  min-height: 42px;
  padding: 8px 10px;
  border: 1px solid var(--line);
  border-radius: 8px;
  color: var(--ink);
  font: inherit;
  font-weight: 800;
}

.count-field input:disabled {
  background: #eef2f3;
  color: var(--muted);
}

.question-count-error {
  min-height: 20px;
  margin: 0;
  color: var(--red);
  font-weight: 800;
  line-height: 1.35;
}

.meter {
  height: 16px;
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #eef2f3;
}

.meter span {
  display: block;
  width: 0;
  height: 100%;
  background: var(--gold);
  transition: width 180ms ease;
}

.missed-list {
  display: grid;
  gap: 8px;
  margin-top: 14px;
}

.missed-item {
  padding: 10px;
  border-left: 5px solid var(--red);
  border-radius: 8px;
  background: #fff4f3;
  color: var(--ink);
  line-height: 1.35;
}

.result-summary {
  display: grid;
  gap: 12px;
}

.result-score {
  margin: 0;
  color: var(--blue);
  font-size: 2.4rem;
  font-weight: 800;
}

.result-meta {
  display: grid;
  gap: 4px;
  padding: 12px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #f8fbfc;
}

.result-meta p {
  margin: 0;
  color: var(--muted);
  line-height: 1.35;
}

.result-meta .result-meta-title {
  color: var(--ink);
  font-weight: 800;
}

.review-item {
  display: grid;
  gap: 6px;
  padding: 12px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #ffffff;
  line-height: 1.35;
}

.review-item span {
  color: var(--muted);
}

.review-item.correct {
  border-left: 5px solid var(--green);
  background: #f3faf7;
}

.review-item.needs-review {
  border-left: 5px solid var(--red);
  background: #fff4f3;
}

@media (max-width: 980px) {
  .setup,
  .review,
  .topic-review {
    grid-template-columns: 1fr;
  }

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

@media (max-width: 640px) {
  .topbar {
    display: block;
  }

  .unit-card {
    grid-template-columns: 1fr;
    gap: 6px;
  }

  .unit-topic-card {
    grid-template-columns: 1fr;
    gap: 6px;
  }

  .question-count-grid {
    grid-template-columns: 1fr;
  }

  .env-review-compare {
    grid-template-columns: 1fr;
  }
}