:root {
  --bg: #f3f6fb;
  --paper: #ffffff;
  --ink: #1d2433;
  --muted: #667085;
  --line: #d7dde8;
  --blue: #2557a7;
  --blue-dark: #17386f;
  --green: #1f7a5c;
  --amber: #b55b00;
  --coral: #c43d4b;
  --violet: #7250b5;
  --shadow: 0 18px 45px rgba(39, 45, 61, 0.14);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  min-height: 100vh;
  margin: 0;
  color: var(--ink);
  font-family:
    Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI",
    sans-serif;
  background:
    linear-gradient(135deg, rgba(37, 87, 167, 0.12), transparent 36%),
    linear-gradient(315deg, rgba(31, 122, 92, 0.14), transparent 40%),
    var(--bg);
}

body[data-subject="french"] {
  background:
    linear-gradient(135deg, rgba(20, 76, 142, 0.13), transparent 34%),
    linear-gradient(315deg, rgba(196, 61, 75, 0.1), transparent 38%),
    linear-gradient(180deg, rgba(31, 122, 92, 0.08), transparent 62%),
    var(--bg);
}

body[data-subject="religion"] {
  background:
    linear-gradient(135deg, rgba(31, 122, 92, 0.14), transparent 34%),
    linear-gradient(315deg, rgba(181, 91, 0, 0.12), transparent 38%),
    linear-gradient(180deg, rgba(114, 80, 181, 0.08), transparent 62%),
    var(--bg);
}

body[data-subject="science"] {
  background:
    linear-gradient(135deg, rgba(20, 108, 128, 0.13), transparent 34%),
    linear-gradient(315deg, rgba(31, 122, 92, 0.12), transparent 38%),
    linear-gradient(180deg, rgba(196, 61, 75, 0.07), transparent 62%),
    var(--bg);
}

button,
input {
  font: inherit;
}

button {
  cursor: pointer;
}

.number-field {
  position: fixed;
  inset: 0;
  z-index: -1;
  width: 100vw;
  height: 100vh;
  opacity: 0.38;
}

.subject-switcher {
  position: sticky;
  top: 0;
  z-index: 20;
  display: flex;
  gap: 8px;
  width: min(1180px, calc(100% - 32px));
  margin: 0 auto;
  padding: 12px 0 0;
  backdrop-filter: blur(18px);
}

.subject-panel[hidden] {
  display: none;
}

.site-header {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(260px, 390px);
  gap: 28px;
  align-items: end;
  width: min(1180px, calc(100% - 32px));
  margin: 0 auto;
  padding: 36px 0 24px;
}

.header-copy h1 {
  max-width: 780px;
  margin: 0;
  font-size: clamp(3rem, 8vw, 7rem);
  line-height: 0.9;
  letter-spacing: 0;
}

.header-copy p {
  max-width: 680px;
  margin: 18px 0 0;
  color: #3f4656;
  font-size: 1.12rem;
  line-height: 1.6;
}

.eyebrow,
.topic-kicker {
  margin: 0 0 10px;
  color: var(--amber);
  font-size: 0.82rem;
  font-weight: 800;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.score-panel {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px;
  padding: 16px;
  border: 1px solid rgba(29, 36, 51, 0.12);
  border-radius: 8px;
  background: rgba(255, 255, 255, 0.86);
  box-shadow: var(--shadow);
  backdrop-filter: blur(18px);
}

.score-panel > div {
  min-height: 86px;
  padding: 14px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #f7fbff;
}

.score-value {
  display: block;
  font-size: 2rem;
  font-weight: 900;
  line-height: 1;
}

.score-label {
  display: block;
  margin-top: 8px;
  color: var(--muted);
  font-size: 0.84rem;
  line-height: 1.35;
}

.primary-button,
.ghost-button,
.toggle-button,
.french-toggle-button,
.religion-toggle-button,
.science-toggle-button,
.subject-tab,
.mini-button,
.answer-button {
  min-height: 42px;
  border: 1px solid transparent;
  border-radius: 8px;
  font-weight: 800;
  transition:
    transform 160ms ease,
    box-shadow 160ms ease,
    background 160ms ease,
    border-color 160ms ease;
}

.primary-button:hover,
.ghost-button:hover,
.toggle-button:hover,
.french-toggle-button:hover,
.religion-toggle-button:hover,
.science-toggle-button:hover,
.subject-tab:hover,
.mini-button:hover,
.answer-button:hover {
  transform: translateY(-1px);
}

.primary-button {
  grid-column: 1 / -1;
  color: #fff;
  background: var(--blue);
  box-shadow: 0 10px 22px rgba(37, 87, 167, 0.24);
}

.primary-button:hover {
  background: var(--blue-dark);
}

.ghost-button,
.toggle-button,
.french-toggle-button,
.religion-toggle-button,
.science-toggle-button,
.subject-tab,
.mini-button,
.answer-button {
  color: var(--ink);
  background: #ffffff;
  border-color: var(--line);
}

.subject-tab {
  min-width: 116px;
  padding: 0 16px;
  background: rgba(255, 255, 255, 0.76);
  box-shadow: 0 10px 26px rgba(39, 45, 61, 0.08);
}

.subject-tab.active {
  color: #ffffff;
  background: var(--blue-dark);
  border-color: var(--blue-dark);
}

.app-shell {
  display: grid;
  grid-template-columns: 290px minmax(0, 1fr);
  gap: 22px;
  width: min(1180px, calc(100% - 32px));
  margin: 0 auto 42px;
  align-items: start;
}

.topic-rail {
  position: sticky;
  top: 14px;
  max-height: calc(100vh - 28px);
  overflow: auto;
  padding: 14px;
  border: 1px solid rgba(29, 36, 51, 0.12);
  border-radius: 8px;
  background: rgba(255, 255, 255, 0.92);
  box-shadow: 0 12px 34px rgba(39, 45, 61, 0.1);
  backdrop-filter: blur(18px);
}

.rail-heading {
  display: flex;
  gap: 10px;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 12px;
  font-weight: 900;
}

.rail-heading .ghost-button {
  min-height: 34px;
  padding: 0 10px;
  font-size: 0.78rem;
}

#topicNav,
#frenchNav,
#religionNav,
#scienceNav {
  display: grid;
  gap: 8px;
}

.topic-nav-button {
  width: 100%;
  min-height: 46px;
  padding: 10px 12px;
  border: 1px solid transparent;
  border-radius: 8px;
  color: var(--ink);
  background: transparent;
  text-align: left;
}

.topic-nav-button:hover,
.topic-nav-button.active {
  border-color: rgba(37, 87, 167, 0.28);
  background: #eef4ff;
}

.topic-nav-button strong {
  display: block;
  line-height: 1.22;
}

.topic-nav-button span {
  display: block;
  margin-top: 3px;
  color: var(--muted);
  font-size: 0.78rem;
}

.content-stage {
  min-width: 0;
}

.toolbar {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  gap: 12px;
  align-items: end;
  margin-bottom: 14px;
}

.search-box {
  display: grid;
  gap: 6px;
  font-size: 0.82rem;
  font-weight: 900;
  color: var(--muted);
}

.search-box input {
  width: 100%;
  min-height: 48px;
  padding: 0 14px;
  border: 1px solid var(--line);
  border-radius: 8px;
  color: var(--ink);
  background: rgba(255, 255, 255, 0.94);
  box-shadow: 0 10px 26px rgba(39, 45, 61, 0.08);
  outline: none;
}

.search-box input:focus {
  border-color: var(--blue);
  box-shadow: 0 0 0 4px rgba(37, 87, 167, 0.16);
}

.view-toggle {
  display: flex;
  gap: 6px;
  padding: 5px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: rgba(255, 255, 255, 0.9);
}

.toggle-button,
.french-toggle-button,
.religion-toggle-button,
.science-toggle-button {
  min-height: 38px;
  padding: 0 14px;
  font-size: 0.88rem;
  background: transparent;
}

.toggle-button.active,
.french-toggle-button.active,
.religion-toggle-button.active,
.science-toggle-button.active {
  color: #fff;
  background: var(--green);
}

.topic-container {
  display: grid;
  gap: 18px;
}

.topic-card {
  overflow: hidden;
  border: 1px solid rgba(29, 36, 51, 0.12);
  border-radius: 8px;
  background: rgba(255, 255, 255, 0.96);
  box-shadow: var(--shadow);
}

.topic-card-header {
  display: flex;
  gap: 18px;
  align-items: start;
  justify-content: space-between;
  padding: 24px;
  background:
    linear-gradient(90deg, rgba(37, 87, 167, 0.12), transparent),
    #f7fbff;
  border-bottom: 1px solid var(--line);
}

.topic-card h2 {
  margin: 0;
  font-size: clamp(1.65rem, 3vw, 2.6rem);
  line-height: 1;
  letter-spacing: 0;
}

.mini-button {
  flex: 0 0 auto;
  padding: 0 14px;
}

.info-grid {
  display: grid;
  grid-template-columns: 1.15fr 0.9fr 0.9fr;
  gap: 1px;
  background: var(--line);
}

.info-block,
.example-block,
.practice-block {
  background: var(--paper);
}

.info-block {
  padding: 22px;
}

.info-block h3,
.example-block h3,
.practice-block h3 {
  margin: 0 0 10px;
  font-size: 1rem;
  letter-spacing: 0;
}

.info-block p,
.example-block p,
.practice-heading p {
  margin: 0;
  color: #3f4656;
  line-height: 1.58;
}

.info-block ul,
.worked-example ol {
  margin: 0;
  padding-left: 20px;
}

.info-block li,
.worked-example li {
  margin: 8px 0;
  color: #3f4656;
  line-height: 1.45;
}

.catches h3 {
  color: var(--coral);
}

.hacks h3 {
  color: var(--green);
}

.visual-block {
  display: grid;
  grid-template-columns: minmax(170px, 0.42fr) minmax(0, 1fr);
  gap: 20px;
  align-items: center;
  padding: 24px;
  border-top: 1px solid var(--line);
  background:
    linear-gradient(135deg, rgba(114, 80, 181, 0.08), transparent 48%),
    #f7fbff;
}

.visual-copy {
  display: grid;
  gap: 8px;
}

.visual-label {
  margin: 0;
  color: var(--violet);
  font-size: 0.78rem;
  font-weight: 900;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.visual-copy h3 {
  margin: 0;
  font-size: 1.24rem;
  line-height: 1.12;
}

.visual-copy p:last-child {
  margin: 0;
  color: #3f4656;
  line-height: 1.5;
}

.visual-stage {
  min-height: 230px;
  padding: 16px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #ffffff;
  overflow: hidden;
}

.visual-stage svg {
  display: block;
  width: 100%;
  height: auto;
  max-height: 270px;
}

.visual-stage text {
  font-family:
    Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI",
    sans-serif;
  letter-spacing: 0;
}

.visual-grid {
  display: grid;
  gap: 12px;
  height: 100%;
}

.chip-row,
.formula-row,
.percent-row,
.sequence-row,
.algebra-row {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  align-items: center;
}

.math-chip,
.formula-chip,
.percent-chip,
.sequence-chip,
.algebra-chip,
.table-cell {
  display: inline-flex;
  min-height: 40px;
  min-width: 46px;
  align-items: center;
  justify-content: center;
  padding: 8px 10px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #f8fafc;
  font-weight: 900;
  line-height: 1.2;
  text-align: center;
}

.math-chip.hot,
.formula-chip.hot,
.percent-chip.hot,
.sequence-chip.hot,
.algebra-chip.hot,
.table-cell.hot {
  color: #ffffff;
  background: var(--blue);
  border-color: var(--blue);
}

.math-chip.warn,
.formula-chip.warn,
.percent-chip.warn,
.sequence-chip.warn,
.algebra-chip.warn,
.table-cell.warn {
  color: #ffffff;
  background: var(--amber);
  border-color: var(--amber);
}

.diagram-note {
  margin: 0;
  padding: 10px 12px;
  border-left: 4px solid var(--green);
  border-radius: 8px;
  color: #174a38;
  background: #e7f7ef;
  font-weight: 800;
  line-height: 1.35;
}

.bar-model {
  display: grid;
  grid-template-columns: repeat(var(--parts), minmax(0, 1fr));
  overflow: hidden;
  min-height: 74px;
  border: 2px solid #17386f;
  border-radius: 8px;
}

.bar-part {
  display: grid;
  place-items: center;
  min-width: 0;
  border-right: 1px solid rgba(23, 56, 111, 0.34);
  color: #17386f;
  background: #eef4ff;
  font-weight: 900;
}

.bar-part:last-child {
  border-right: 0;
}

.bar-part.fill {
  color: #ffffff;
  background: var(--green);
}

.mini-table {
  display: grid;
  grid-template-columns: repeat(4, minmax(54px, 1fr));
  gap: 6px;
}

.table-cell {
  min-height: 52px;
}

.table-cell.head {
  color: var(--blue-dark);
  background: #eef4ff;
}

.conversion-strip {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 8px;
}

.conversion-box {
  min-height: 86px;
  padding: 12px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #f8fafc;
}

.conversion-box strong,
.chunk-box strong {
  display: block;
  margin-bottom: 6px;
  color: var(--blue-dark);
}

.chunk-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 8px;
}

.chunk-box {
  min-height: 92px;
  padding: 10px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #f8fafc;
  text-align: center;
}

.chunk-box.hot {
  color: #ffffff;
  background: var(--green);
  border-color: var(--green);
}

.chunk-box.hot strong {
  color: #ffffff;
}

.balance {
  display: grid;
  gap: 10px;
}

.balance-bar {
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  gap: 12px;
  align-items: center;
}

.pan {
  min-height: 86px;
  padding: 12px;
  border: 2px solid var(--blue);
  border-radius: 8px;
  background: #eef4ff;
  text-align: center;
  font-weight: 900;
}

.pivot {
  color: var(--amber);
  font-size: 2rem;
  font-weight: 900;
}

.example-block {
  padding: 24px;
  border-top: 1px solid var(--line);
}

.worked-example {
  display: grid;
  gap: 10px;
}

.example-question {
  display: inline-flex;
  width: fit-content;
  max-width: 100%;
  padding: 10px 12px;
  border: 1px solid rgba(181, 91, 0, 0.28);
  border-radius: 8px;
  color: #612f00;
  background: #fff5df;
  font-weight: 900;
}

.practice-block {
  padding: 24px;
  border-top: 1px solid var(--line);
}

.practice-heading {
  display: flex;
  gap: 16px;
  align-items: start;
  justify-content: space-between;
  margin-bottom: 16px;
}

.practice-heading .primary-button {
  grid-column: auto;
  min-width: 150px;
  padding: 0 14px;
}

.questions-list {
  display: grid;
  gap: 12px;
  margin: 0;
  padding-left: 22px;
}

.question-card {
  padding: 14px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #ffffff;
}

.question-card p {
  margin: 0;
  line-height: 1.5;
}

.question-text {
  font-weight: 850;
}

.answer-button {
  min-height: 34px;
  margin-top: 10px;
  padding: 0 10px;
  font-size: 0.84rem;
}

.answer-text {
  display: none;
  margin-top: 10px;
  padding: 10px;
  border-radius: 8px;
  color: #174a38;
  background: #e7f7ef;
  font-weight: 750;
}

.question-card.revealed .answer-text {
  display: block;
}

.answer-fact {
  display: none;
  margin-top: 8px;
  padding: 10px;
  border-radius: 8px;
  color: #53310a;
  background: #fff5df;
  line-height: 1.45;
}

.question-card.revealed .answer-fact {
  display: block;
}

.empty-state {
  padding: 28px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--paper);
  color: var(--muted);
  font-weight: 800;
}

.french-side-panel {
  display: grid;
  gap: 12px;
}

.french-hero-image {
  display: block;
  width: 100%;
  aspect-ratio: 16 / 9;
  object-fit: cover;
  border: 1px solid rgba(29, 36, 51, 0.12);
  border-radius: 8px;
  box-shadow: var(--shadow);
}

.french-topic-card .topic-card-header {
  background:
    linear-gradient(90deg, rgba(196, 61, 75, 0.1), transparent),
    linear-gradient(135deg, rgba(31, 122, 92, 0.1), transparent 62%),
    #f7fbff;
}

.french-info-grid {
  grid-template-columns: 1.1fr 0.95fr 0.95fr;
}

.french-fact h3,
.french-remember h3 {
  color: var(--blue);
}

.french-visual-stage {
  display: grid;
  gap: 14px;
}

.vocab-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(135px, 1fr));
  gap: 10px;
}

.vocab-tile,
.phrase-tile,
.verb-tile,
.pattern-card,
.reading-card {
  min-width: 0;
  padding: 12px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #f8fafc;
}

.vocab-tile strong,
.phrase-tile strong,
.verb-tile strong,
.pattern-card strong,
.reading-card strong {
  display: block;
  color: var(--blue-dark);
  line-height: 1.25;
}

.vocab-tile span,
.phrase-tile span,
.verb-tile span,
.pattern-card span {
  display: block;
  margin-top: 5px;
  color: #3f4656;
  line-height: 1.35;
}

.phrase-grid,
.verb-grid,
.pattern-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(170px, 1fr));
  gap: 10px;
}

.pattern-card.hot {
  color: #ffffff;
  background: var(--blue);
  border-color: var(--blue);
}

.pattern-card.hot strong,
.pattern-card.hot span {
  color: #ffffff;
}

.french-rule {
  margin: 0;
  padding: 12px 14px;
  border-left: 4px solid var(--coral);
  border-radius: 8px;
  color: #6c1c25;
  background: #fff0f1;
  font-weight: 850;
  line-height: 1.42;
}

.future-line {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  align-items: center;
}

.future-chip {
  display: inline-flex;
  min-height: 42px;
  align-items: center;
  justify-content: center;
  padding: 8px 12px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #ffffff;
  font-weight: 900;
}

.future-chip.hot {
  color: #ffffff;
  background: var(--green);
  border-color: var(--green);
}

.future-chip.warn {
  color: #ffffff;
  background: var(--amber);
  border-color: var(--amber);
}

.reading-card {
  color: #273142;
  background:
    linear-gradient(90deg, rgba(37, 87, 167, 0.08), transparent),
    #ffffff;
  line-height: 1.62;
}

.reading-card p {
  margin: 8px 0 0;
}

.religion-topic-card .topic-card-header {
  background:
    linear-gradient(90deg, rgba(31, 122, 92, 0.12), transparent),
    linear-gradient(135deg, rgba(181, 91, 0, 0.12), transparent 62%),
    #f7fbff;
}

.religion-info-grid {
  grid-template-columns: 1.05fr 1fr 0.95fr;
}

.religion-core h3,
.religion-remember h3 {
  color: var(--green);
}

.religion-activity h3 {
  color: var(--amber);
}

.religion-story-block {
  display: grid;
  grid-template-columns: minmax(260px, 0.95fr) minmax(0, 1fr);
  gap: 22px;
  align-items: center;
  padding: 24px;
  border-top: 1px solid var(--line);
  background:
    linear-gradient(135deg, rgba(114, 80, 181, 0.08), transparent 46%),
    #fbfcff;
}

.religion-story-block img {
  display: block;
  width: 100%;
  aspect-ratio: 4 / 3;
  object-fit: cover;
  border: 1px solid rgba(29, 36, 51, 0.12);
  border-radius: 8px;
  box-shadow: 0 14px 34px rgba(39, 45, 61, 0.13);
}

.religion-story-copy {
  display: grid;
  gap: 10px;
}

.religion-narrative {
  margin: 0;
  color: #303849;
  font-size: 1.06rem;
  line-height: 1.72;
}

.religion-decision-block,
.religion-writing-block {
  padding: 24px;
  border-top: 1px solid var(--line);
  background:
    linear-gradient(90deg, rgba(31, 122, 92, 0.08), transparent),
    #ffffff;
}

.religion-decision-block h3,
.religion-writing-block h3 {
  margin: 0 0 16px;
  font-size: 1.18rem;
  line-height: 1.2;
}

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

.decision-card {
  min-width: 0;
  padding: 14px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #f8fafc;
}

.decision-card h4 {
  margin: 0 0 10px;
  color: var(--blue-dark);
  font-size: 0.98rem;
  line-height: 1.25;
}

.decision-card p,
.religion-writing-block li {
  color: #3f4656;
  line-height: 1.48;
}

.decision-card p {
  margin: 8px 0 0;
}

.decision-card strong {
  color: var(--ink);
}

.decision-reason {
  padding: 10px;
  border-left: 4px solid var(--green);
  border-radius: 8px;
  color: #174a38;
  background: #e7f7ef;
  font-weight: 750;
}

.religion-writing-block ol {
  display: grid;
  gap: 10px;
  margin: 0;
  padding-left: 22px;
}

.religion-question-card .answer-text {
  color: #174a38;
}

.science-topic-card .topic-card-header {
  background:
    linear-gradient(90deg, rgba(20, 108, 128, 0.12), transparent),
    linear-gradient(135deg, rgba(31, 122, 92, 0.1), transparent 62%),
    #f7fbff;
}

.science-exam-strip {
  display: grid;
  grid-template-columns: 0.7fr 1.45fr 1fr;
  gap: 1px;
  border-top: 1px solid var(--line);
  background: var(--line);
}

.science-fact-card {
  min-width: 0;
  padding: 16px;
  background: #ffffff;
}

.science-fact-card strong {
  display: block;
  margin-bottom: 6px;
  color: #146c80;
  font-size: 0.8rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.science-fact-card span {
  color: #3f4656;
  line-height: 1.45;
}

.science-visual-block {
  grid-template-columns: 1fr;
  background:
    linear-gradient(135deg, rgba(20, 108, 128, 0.08), transparent 48%),
    #f7fbff;
}

.science-visual-block .visual-copy {
  max-width: 760px;
}

.science-visual-stage {
  display: grid;
  align-content: center;
}

.science-diagram {
  display: grid;
  gap: 12px;
}

.science-diagram-heading {
  display: grid;
  gap: 4px;
}

.science-diagram-heading strong {
  color: #17386f;
  font-size: 1.02rem;
  line-height: 1.2;
}

.science-diagram-heading span {
  color: #3f4656;
  font-size: 0.9rem;
  line-height: 1.4;
}

.science-diagram-artwork {
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #ffffff;
}

.science-diagram-svg {
  display: block;
  width: 100%;
  height: auto;
}

.science-diagram-labels {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 8px;
}

.science-diagram-label {
  min-width: 0;
  padding: 9px 10px;
  border: 1px solid rgba(20, 108, 128, 0.2);
  border-radius: 8px;
  color: #174a38;
  background: #e7f7ef;
  font-size: 0.82rem;
  font-weight: 850;
  line-height: 1.28;
  text-align: center;
}

.science-diagram-tile {
  min-width: 0;
  min-height: 104px;
  display: grid;
  align-content: center;
  gap: 8px;
  padding: 12px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #f8fafc;
  text-align: center;
}

.science-diagram-tile strong {
  color: var(--blue-dark);
  font-size: 1rem;
  line-height: 1.15;
}

.science-diagram-tile span {
  color: #3f4656;
  font-size: 0.88rem;
  line-height: 1.25;
}

.science-diagram-tile.hot {
  color: #ffffff;
  background: #146c80;
  border-color: #146c80;
}

.science-diagram-tile.hot strong,
.science-diagram-tile.hot span {
  color: #ffffff;
}

.science-info-grid {
  grid-template-columns: 1fr 0.95fr 0.95fr;
}

.science-remember h3 {
  color: #146c80;
}

.science-traps h3 {
  color: var(--coral);
}

.science-command h3 {
  color: var(--green);
}

.science-question-meta {
  display: inline-flex;
  width: fit-content;
  margin-bottom: 8px;
  padding: 5px 8px;
  border-radius: 8px;
  color: #ffffff;
  background: #146c80;
  font-size: 0.78rem;
  font-weight: 900;
}

.science-mark-scheme {
  color: #174a38;
}

.science-mark-scheme ul {
  margin: 8px 0 0;
  padding-left: 20px;
}

.science-mark-scheme li {
  margin: 6px 0;
  line-height: 1.4;
}

@media (max-width: 940px) {
  .site-header,
  .app-shell {
    grid-template-columns: 1fr;
  }

  .topic-rail {
    position: relative;
    top: auto;
    max-height: none;
  }

  #topicNav {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

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

  .visual-block {
    grid-template-columns: 1fr;
  }

  .french-info-grid {
    grid-template-columns: 1fr;
  }

  .religion-info-grid,
  .religion-story-block,
  .decision-grid,
  .science-exam-strip,
  .science-info-grid {
    grid-template-columns: 1fr;
  }

  .science-diagram-labels {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (max-width: 640px) {
  .subject-switcher,
  .site-header,
  .app-shell {
    width: min(100% - 20px, 1180px);
  }

  .subject-switcher {
    gap: 6px;
  }

  .subject-tab {
    flex: 1 1 0;
    min-width: 0;
    padding: 0 10px;
  }

  .site-header {
    padding-top: 22px;
  }

  .score-panel,
  .toolbar,
  #topicNav,
  #frenchNav,
  #religionNav,
  #scienceNav {
    grid-template-columns: 1fr;
  }

  .header-copy h1 {
    font-size: clamp(2.8rem, 16vw, 4.7rem);
  }

  .topic-card-header,
  .practice-heading {
    flex-direction: column;
  }

  .mini-button,
  .practice-heading .primary-button {
    width: 100%;
  }

  .topic-card-header,
  .info-block,
  .visual-block,
  .example-block,
  .practice-block {
    padding: 18px;
  }

  .visual-stage {
    padding: 12px;
  }

  .conversion-strip,
  .chunk-grid,
  .phrase-grid,
  .verb-grid,
  .pattern-grid,
  .decision-grid,
  .science-diagram-labels {
    grid-template-columns: 1fr;
  }

  .religion-story-block,
  .religion-decision-block,
  .religion-writing-block,
  .science-fact-card {
    padding: 18px;
  }

  .mini-table {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}