/* ---------------------------------------------------------
   HSC Standard Maths — Band 6 Revision Checklist
   Calm, minimal, clear.
--------------------------------------------------------- */

:root {
  --paper:      #F7F6F2;
  --paper-raised: #FFFFFF;
  --ink:        #23272B;
  --ink-soft:   #666C71;
  --ink-faint:  #9CA1A5;
  --line:       #E4E1DA;

  --algebra:     #5C7A99;
  --measurement: #6E8F6B;
  --financial:   #C08A4E;
  --statistical: #8C6A9C;
  --networks:    #3E7C82;

  --level1:      #3B7DC4;
  --level1-bg:   #E3EFFB;
  --level2:      #C0703E;
  --level2-bg:   #F7EAE0;
  --level3:      #7A5C9E;
  --level3-bg:   #EFE7F5;

  --radius: 14px;
  --radius-sm: 8px;

  --font-display: "Fraunces", Georgia, serif;
  --font-body: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  --font-mono: "IBM Plex Mono", ui-monospace, SFMono-Regular, monospace;
}

* { box-sizing: border-box; }

html { -webkit-font-smoothing: antialiased; }

body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: var(--font-body);
  line-height: 1.55;
}

a { color: inherit; }

.wrap {
  max-width: 1320px;
  margin: 0 auto;
  padding: 0 32px;
}

.wrap-narrow {
  max-width: 760px;
}

/* ---------- Header ---------- */

.site-header {
  padding: 56px 0 40px;
  border-bottom: 1px solid var(--line);
}

.hero-center {
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
}

.site-header .eyebrow {
  display: inline-block;
  align-self: flex-start;
  font-family: var(--font-body);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.09em;
  text-transform: uppercase;
  color: #3B5BD6;
  background: #E8ECFB;
  padding: 6px 15px;
  border-radius: 999px;
  margin: 0 0 18px;
}

.site-header h1 {
  font-family: var(--font-body);
  font-weight: 800;
  font-size: clamp(34px, 6vw, 56px);
  line-height: 1.08;
  margin: 0 0 16px;
  letter-spacing: -0.02em;
}

.site-header p.lede {
  color: var(--ink-soft);
  font-size: 16px;
  max-width: 56ch;
  margin: 0 auto 28px;
}

/* ---------- Overall progress dashboard ---------- */

.dashboard {
  display: flex;
  align-items: center;
  gap: 28px;
  flex-wrap: wrap;
}

.ring-big {
  flex-shrink: 0;
}

.ring-big .ring-label {
  font-family: var(--font-display);
  font-size: 26px;
  font-weight: 600;
}

.ring-big .ring-sub {
  font-family: var(--font-mono);
  font-size: 11px;
  fill: var(--ink-faint);
}

.dashboard-note {
  font-size: 14px;
  color: var(--ink-soft);
  max-width: 42ch;
}

.dashboard-note strong { color: var(--ink); font-weight: 600; }

/* ---------- Year / strand sections ---------- */

.year-section { padding: 40px 0 8px; }

.year-heading {
  font-family: var(--font-mono);
  font-size: 13px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--ink-soft);
  margin: 0 0 20px;
  display: flex;
  align-items: baseline;
  gap: 10px;
}

.year-heading-rule {
  flex: 1;
  border-bottom: 1px solid var(--line);
}

.year-count {
  font-variant-numeric: tabular-nums;
  color: var(--ink-faint);
}

.strand-title {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 13px;
  color: var(--ink-soft);
  margin: 0 0 12px;
}

.strand-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  flex-shrink: 0;
}

.topic-list {
  display: flex;
  flex-direction: column;
  gap: 10px;
  margin-bottom: 32px;
}

.topic-row {
  display: flex;
  align-items: center;
  gap: 16px;
  background: var(--paper-raised);
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
  padding: 16px 20px;
  text-decoration: none;
  color: inherit;
  transition: border-color 120ms ease, transform 120ms ease, box-shadow 120ms ease;
}

.topic-row:hover {
  border-color: var(--accent, var(--ink-faint));
  box-shadow: 0 4px 16px rgba(35, 39, 43, 0.06);
  transform: translateY(-1px);
}

.topic-row:focus-visible {
  outline: 2px solid var(--accent, var(--ink));
  outline-offset: 2px;
}

.topic-row-dot {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: var(--accent, var(--ink-faint));
  flex-shrink: 0;
}

.topic-row-info {
  flex: 1;
  min-width: 0;
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.topic-row-eyebrow {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  color: var(--accent, var(--ink-soft));
}

.topic-row-title {
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 17px;
  line-height: 1.3;
}

.topic-row-progress {
  display: flex;
  align-items: center;
  gap: 10px;
  flex-shrink: 0;
  width: 200px;
}

.topic-row-bar {
  flex: 1;
  height: 6px;
  background: var(--line);
  border-radius: 3px;
  overflow: hidden;
}

.topic-row-bar > span {
  display: block;
  height: 100%;
  background: var(--accent, var(--ink-faint));
  border-radius: 3px;
  transition: width 200ms ease;
}

.topic-row-count {
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--ink-faint);
  white-space: nowrap;
  min-width: 46px;
  text-align: right;
  font-variant-numeric: tabular-nums;
}

.topic-row-chevron {
  flex-shrink: 0;
  color: var(--ink-faint);
  transition: transform 120ms ease, color 120ms ease;
}
.topic-row-chevron svg { width: 14px; height: 14px; }
.topic-row:hover .topic-row-chevron { color: var(--accent, var(--ink-soft)); transform: translateX(2px); }

@media (max-width: 640px) {
  .topic-row { flex-wrap: wrap; }
  .topic-row-progress { width: 100%; order: 3; }
}

.site-footer {
  padding: 48px 0 64px;
  color: var(--ink-faint);
  font-size: 13px;
  border-top: 1px solid var(--line);
  margin-top: 40px;
}

.reset-link {
  background: none;
  border: none;
  padding: 0;
  font: inherit;
  color: var(--ink-faint);
  text-decoration: underline;
  cursor: pointer;
}
.reset-link:hover { color: var(--ink-soft); }

/* ---------- Topic (landing) page ---------- */

.breadcrumb {
  padding: 28px 0 0;
  font-size: 13px;
}

.quick-nav {
  display: flex;
  flex-direction: row;
  gap: 10px;
  padding: 10px 0 4px;
}

.quick-nav-group {
  flex: 1;
  min-width: 0;
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
  padding: 8px 10px 9px;
  background: var(--paper-raised);
}

.quick-nav-group-label {
  margin: 0 0 6px;
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--ink-faint);
}

.quick-nav-grid {
  display: flex;
  gap: 6px;
}

.quick-nav-item {
  flex: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 4px;
  padding: 5px 6px 5px;
  border: 1px solid var(--line);
  border-radius: 6px;
  text-decoration: none;
  background: var(--paper);
  transition: border-color 120ms ease, transform 120ms ease, box-shadow 120ms ease;
}
.quick-nav-item:hover {
  border-color: var(--accent, var(--ink-faint));
  transform: translateY(-1px);
}
.quick-nav-item.is-current {
  border-color: var(--accent);
  box-shadow: inset 0 0 0 1px var(--accent);
  background: var(--paper-raised);
}

.quick-nav-code {
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 600;
  color: var(--accent, var(--ink-soft));
}
.quick-nav-item.is-current .quick-nav-code { color: var(--ink); }

.quick-nav-bar {
  width: 100%;
  height: 3px;
  background: var(--line);
  border-radius: 2px;
  overflow: hidden;
}
.quick-nav-bar > span {
  display: block;
  height: 100%;
  background: var(--accent, var(--ink-faint));
  border-radius: 2px;
  transition: width 200ms ease;
}

@media (max-width: 760px) {
  .quick-nav { flex-direction: column; }
  .quick-nav-grid { flex-wrap: wrap; }
  .quick-nav-item { flex: 1 1 70px; }
}

.breadcrumb a {
  text-decoration: none;
  color: var(--ink-soft);
}
.breadcrumb a:hover { color: var(--ink); }

.topic-header {
  padding: 20px 0 32px;
  border-bottom: 1px solid var(--line);
}

.topic-header .strand-title { margin-bottom: 10px; }

.topic-header h1 {
  font-family: var(--font-display);
  font-weight: 600;
  font-size: clamp(26px, 4.5vw, 36px);
  line-height: 1.18;
  margin: 0 0 18px;
}

.topic-header h1 .code-tag {
  font-family: var(--font-mono);
  font-size: 0.5em;
  font-weight: 500;
  color: var(--accent);
  vertical-align: middle;
  margin-right: 10px;
  border: 1px solid var(--accent);
  border-radius: 6px;
  padding: 3px 7px;
}

.progress-row {
  display: flex;
  align-items: center;
  gap: 14px;
}

.progress-row .bar {
  flex: 1;
  height: 8px;
  background: var(--line);
  border-radius: 4px;
  overflow: hidden;
}

.progress-row .bar > span {
  display: block;
  height: 100%;
  background: var(--accent);
  border-radius: 4px;
  width: 0%;
  transition: width 250ms ease;
}

.progress-row .stat {
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--ink-soft);
  white-space: nowrap;
  min-width: 64px;
  text-align: right;
}

/* ---------- Checklist ---------- */

.practice-hint {
  margin: 0;
  font-size: 13px;
  color: var(--ink-faint);
}
.practice-hint strong { color: var(--ink-soft); font-weight: 600; }

.stats-badge {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  margin: 0 0 20px;
  padding: 7px 16px;
  background: var(--level1-bg);
  border: 1px solid transparent;
  border-radius: 999px;
  font-family: var(--font-mono);
  font-size: 12.5px;
  color: var(--level1);
}
.stats-badge strong {
  color: var(--ink);
  font-weight: 600;
}

.how-box {
  margin: 0 0 28px;
  padding: 16px 20px;
  background: var(--level1-bg);
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
}
.how-label {
  margin: 0 0 7px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  font-weight: 600;
  color: var(--level1);
}
.how-text {
  margin: 0;
  font-size: 14px;
  line-height: 1.6;
  color: var(--ink-soft);
}
.how-text strong { color: var(--ink); font-weight: 600; }

.toolbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 24px;
  padding-top: 20px;
  border-top: 1px solid var(--line);
}

.year-tabs {
  display: flex;
  gap: 4px;
  background: var(--paper-raised);
  border: 1px solid var(--line);
  border-radius: 999px;
  padding: 3px;
}

.year-tab {
  background: none;
  border: none;
  border-radius: 999px;
  padding: 6px 14px;
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--ink-soft);
  cursor: pointer;
  transition: background 120ms ease, color 120ms ease;
}
.year-tab:hover { color: var(--ink); }
.year-tab.active {
  background: var(--level1);
  color: white;
}

.toolbar-right {
  display: flex;
  align-items: center;
  gap: 14px;
}

.hide-ticked-toggle {
  display: flex;
  align-items: center;
  gap: 8px;
  cursor: pointer;
  user-select: none;
}
.hide-ticked-toggle input {
  position: absolute;
  opacity: 0;
  width: 1px;
  height: 1px;
}
.toggle-track {
  width: 34px;
  height: 20px;
  border-radius: 999px;
  background: var(--line);
  position: relative;
  transition: background 150ms ease;
  flex-shrink: 0;
}
.toggle-thumb {
  position: absolute;
  top: 2px;
  left: 2px;
  width: 16px;
  height: 16px;
  border-radius: 50%;
  background: white;
  box-shadow: 0 1px 2px rgba(0,0,0,0.15);
  transition: transform 150ms ease;
}
.hide-ticked-toggle input:checked + .toggle-track {
  background: var(--ink);
}
.hide-ticked-toggle input:checked + .toggle-track .toggle-thumb {
  transform: translateX(14px);
}
.toggle-label {
  font-size: 13px;
  color: var(--ink-soft);
}

.chip-btn {
  background: none;
  border: 1px solid var(--line);
  border-radius: 999px;
  padding: 6px 14px;
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--ink-soft);
  cursor: pointer;
  transition: border-color 120ms ease, color 120ms ease;
  white-space: nowrap;
}
.chip-btn:hover {
  border-color: var(--accent, var(--ink-faint));
  color: var(--ink);
}

.topic-toolbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  margin-top: 16px;
}

.topic-card.is-hidden { display: none; }
.year-section.is-hidden { display: none; }

.checklist {
  list-style: none;
  margin: 32px 0;
  padding: 0;
}

.checklist li {
  border-bottom: 1px solid var(--line);
}

.checklist li:first-child { border-top: 1px solid var(--line); }

.item-row {
  display: flex;
  align-items: center;
  gap: 12px;
}

.item-text-btn {
  flex: 1;
  min-width: 0;
  display: flex;
  align-items: center;
  gap: 14px;
  text-align: left;
  background: none;
  border: none;
  padding: 13px 4px;
  font: inherit;
  color: inherit;
  cursor: pointer;
}

.item-text-btn .check-text {
  flex: 1;
  font-size: 15px;
  line-height: 1.5;
}

.practice-pill {
  flex-shrink: 0;
  display: inline-flex;
  align-items: center;
  gap: 6px;
  background: var(--level1-bg);
  color: var(--level1);
  padding: 7px 14px;
  border-radius: 999px;
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  transition: background 120ms ease, color 120ms ease;
}
.practice-pill svg {
  width: 11px;
  height: 11px;
  transition: transform 150ms ease;
}
.item-text-btn:hover .practice-pill { background: var(--level1); color: white; }
.item-text-btn[aria-expanded="true"] .practice-pill { background: var(--level1); color: white; }
.item-text-btn[aria-expanded="true"] .practice-pill svg { transform: rotate(180deg); }

.item-checkbox {
  flex-shrink: 0;
  display: flex;
  align-items: center;
  padding: 15px 4px;
  cursor: pointer;
}

.item-checkbox input[type="checkbox"] {
  position: absolute;
  opacity: 0;
  width: 1px;
  height: 1px;
}

.item-checkbox .check-box {
  width: 24px;
  height: 24px;
  border-radius: 7px;
  border: 2px solid var(--ink-faint);
  display: flex;
  align-items: center;
  justify-content: center;
  transition: background 120ms ease, border-color 120ms ease;
}
.item-checkbox .check-box svg {
  width: 14px;
  height: 14px;
  opacity: 0;
  transform: scale(0.6);
  transition: opacity 120ms ease, transform 120ms ease;
}
.item-checkbox input:checked + .check-box {
  background: var(--ink);
  border-color: var(--ink);
  box-shadow: 0 1px 3px rgba(35, 39, 43, 0.25);
}
.item-checkbox input:checked + .check-box svg { opacity: 1; transform: scale(1); }
.item-checkbox input:hover + .check-box {
  border-color: var(--accent, var(--ink-soft));
}
.item-checkbox input:focus-visible + .check-box {
  outline: 2px solid var(--accent, var(--ink));
  outline-offset: 2px;
}

.item-formula {
  margin-top: 8px;
  padding: 10px 4px 4px;
  overflow-x: auto;
}

.question-panel {
  display: flex;
  flex-direction: column;
  gap: 10px;
  margin: 4px 4px 20px;
}

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

.q-block {
  background: var(--paper-raised);
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
  padding: 16px 18px;
  box-shadow: 0 1px 3px rgba(35, 39, 43, 0.04);
}

.q-block--fluency { border-left: 3px solid var(--level1); }
.q-block--challenge { border-left: 3px solid var(--level2); }
.q-block--extension { border-left: 3px solid var(--level3); }

.q-level {
  margin: 0 0 7px;
  font-family: var(--font-mono);
  font-size: 10.5px;
  font-weight: 600;
  letter-spacing: 0.06em;
  text-transform: uppercase;
}

.q-block--fluency .q-level { color: var(--level1); }
.q-block--challenge .q-level { color: var(--level2); }
.q-block--extension .q-level { color: var(--level3); }

.q-text {
  margin: 0;
  font-size: 14.5px;
  line-height: 1.55;
  color: var(--ink-soft);
}

.q-text .katex { font-size: 1.02em; }
.item-formula .katex-display { margin: 0.3em 0; }

.cartesian-plane {
  display: block;
  margin: 10px 0 4px;
  background: var(--paper-raised);
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
}

.network-diagram {
  display: block;
  margin: 10px 0 4px;
  max-width: 100%;
  height: auto;
  background: var(--paper-raised);
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
}

.reveal-buttons {
  display: flex;
  gap: 8px;
  margin-top: 10px;
}

.reveal-btn {
  background: none;
  border: 1px solid var(--line);
  border-radius: 999px;
  padding: 4px 12px;
  font-family: var(--font-body);
  font-size: 12px;
  font-weight: 500;
  color: var(--ink-soft);
  cursor: pointer;
  transition: border-color 120ms ease, color 120ms ease, background 120ms ease;
}
.reveal-btn:hover {
  border-color: var(--accent, var(--ink-faint));
  color: var(--ink);
}
.reveal-btn[aria-expanded="true"] {
  background: var(--accent, var(--ink-faint));
  border-color: var(--accent, var(--ink-faint));
  color: white;
}

.reveal-panel {
  margin-top: 8px;
  padding: 10px 12px;
  background: var(--paper);
  border-left: 2px solid var(--accent, var(--ink-faint));
  border-radius: 4px;
}

.q-block--fluency .reveal-btn:hover { border-color: var(--level1); color: var(--ink); }
.q-block--fluency .reveal-btn[aria-expanded="true"] { background: var(--level1); border-color: var(--level1); }
.q-block--fluency .reveal-panel { border-left-color: var(--level1); }

.q-block--challenge .reveal-btn:hover { border-color: var(--level2); color: var(--ink); }
.q-block--challenge .reveal-btn[aria-expanded="true"] { background: var(--level2); border-color: var(--level2); }
.q-block--challenge .reveal-panel { border-left-color: var(--level2); }

.q-block--extension .reveal-btn:hover { border-color: var(--level3); color: var(--ink); }
.q-block--extension .reveal-btn[aria-expanded="true"] { background: var(--level3); border-color: var(--level3); }
.q-block--extension .reveal-panel { border-left-color: var(--level3); }

.ans-text {
  margin: 0;
  font-size: 14px;
  font-weight: 600;
  color: var(--ink);
}

.sol-text {
  margin: 0;
  font-size: 13.5px;
  line-height: 1.5;
  color: var(--ink-soft);
  font-family: var(--font-mono);
}

.check-text {
  font-size: 15px;
  line-height: 1.5;
  padding-top: 1px;
  transition: color 150ms ease;
}

.item-row:has(input:checked) .check-text {
  color: var(--ink-faint);
  text-decoration: line-through;
  text-decoration-color: var(--line);
  text-decoration-thickness: 1.5px;
}

.topic-footer-nav {
  display: flex;
  justify-content: space-between;
  gap: 16px;
  padding: 24px 0 56px;
}

.nav-link {
  display: flex;
  flex-direction: column;
  text-decoration: none;
  color: inherit;
  max-width: 45%;
  padding: 14px 16px;
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
  transition: border-color 120ms ease;
}
.nav-link:hover { border-color: var(--accent); }
.nav-link.next { text-align: right; margin-left: auto; }

.nav-link .nav-label {
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--ink-faint);
  text-transform: uppercase;
  letter-spacing: 0.06em;
}
.nav-link .nav-title {
  font-size: 14px;
  font-weight: 600;
  margin-top: 3px;
}

@media (max-width: 560px) {
  .site-header { padding: 40px 0 28px; }
  .dashboard { gap: 18px; }
  .card-grid { grid-template-columns: 1fr; }
}

@media (prefers-reduced-motion: reduce) {
  * { transition: none !important; }
}

/* --- Topic header redesign (pilot, scoped to .header-v2) --- */
.header-v2 .topic-header { padding: 6px 0 22px; border-bottom: none; }
.header-v2 .strand-title {
  font-family: var(--font-body);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: #3B5BD6;
  margin-bottom: 14px;
}
.header-v2 .strand-dot { display: none; }
.header-v2 .topic-header h1 {
  font-family: var(--font-body);
  font-weight: 800;
  font-size: clamp(30px, 5vw, 46px);
  line-height: 1.05;
  letter-spacing: -0.02em;
  margin: 0;
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 14px;
}
.header-v2 .topic-header h1 .code-tag {
  font-family: var(--font-body);
  font-size: 0.42em;
  font-weight: 700;
  color: #3B5BD6;
  background: #E8ECFB;
  border: none;
  border-radius: 10px;
  padding: 6px 12px;
  margin-right: 0;
}
.header-v2 .head-count {
  font-family: var(--font-mono);
  font-size: 0.4em;
  font-weight: 500;
  letter-spacing: 0;
  color: var(--ink-faint);
}
.header-v2 .topic-toolbar { margin-top: 16px; border-top: none; padding-top: 0; }
.header-v2 .quick-nav { flex-direction: column; gap: 9px; padding: 4px 0 22px; }
.header-v2 .quick-nav-group {
  display: flex;
  align-items: center;
  gap: 12px;
  border: none;
  background: none;
  padding: 0;
}
.header-v2 .quick-nav-group-label {
  margin: 0;
  flex-shrink: 0;
  width: 40px;
  font-size: 11px;
  color: var(--ink-faint);
}
.header-v2 .quick-nav-grid { flex-wrap: wrap; gap: 8px; }
.header-v2 .quick-nav-item {
  flex: 0 0 auto;
  flex-direction: row;
  min-width: 46px;
  justify-content: center;
  padding: 7px 15px;
  border-radius: 10px;
  background: var(--paper-raised);
  border: 1px solid var(--line);
}
.header-v2 .quick-nav-item:hover { transform: none; border-color: #3B5BD6; }
.header-v2 .quick-nav-item.is-current {
  background: #3B5BD6;
  border-color: #3B5BD6;
  box-shadow: none;
}
.header-v2 .quick-nav-item.is-current .quick-nav-code { color: #fff; }
.header-v2 .quick-nav-code {
  font-family: var(--font-body);
  font-size: 13px;
  font-weight: 700;
  color: var(--ink);
}
.header-v2 .quick-nav-bar { display: none; }

/* --- "More examples" cycler on a question level --- */
.q-block-head {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 12px;
}
.q-block-head .q-level { margin: 0; }
.more-btn {
  flex-shrink: 0;
  display: inline-flex;
  align-items: center;
  gap: 5px;
  background: none;
  border: 1px solid var(--line);
  border-radius: 999px;
  padding: 3px 11px;
  font-family: var(--font-body);
  font-size: 11px;
  font-weight: 500;
  color: var(--ink-soft);
  cursor: pointer;
  transition: border-color 120ms ease, color 120ms ease, background 120ms ease;
}
.more-btn:hover { border-color: var(--ink-faint); color: var(--ink); }
.q-block--fluency .more-btn:hover { border-color: var(--level1); color: var(--level1); }
.q-block--challenge .more-btn:hover { border-color: var(--level2); color: var(--level2); }
.q-block--extension .more-btn:hover { border-color: var(--level3); color: var(--level3); }
.more-count { opacity: 0.65; font-variant-numeric: tabular-nums; }

/* --- Topic intro: quick tips + summary notes --- */
.tips-box {
  margin: 0 0 18px;
  padding: 17px 22px 18px;
  background: #FDFAF0;
  border: 1px solid #F0E4C0;
  border-left: 4px solid #E4AE38;
  border-radius: 16px;
}
.tips-label {
  display: flex;
  align-items: center;
  gap: 8px;
  margin: 0 0 12px;
  font-family: var(--font-body);
  font-size: 13px;
  letter-spacing: 0.07em;
  text-transform: uppercase;
  font-weight: 700;
  color: #B08519;
}
.tips-label .tips-icon { font-size: 15px; }
.tips-sub {
  text-transform: none;
  letter-spacing: 0;
  font-weight: 500;
  color: #C29A4C;
}
.tips-grid {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  gap: 9px 34px;
}
.tips-grid li {
  position: relative;
  padding-left: 22px;
  margin: 3px 0;
  font-size: 14px;
  line-height: 1.6;
  color: #47536B;
}
.tips-grid li::before {
  content: "\2192";
  position: absolute;
  left: 0;
  color: #E0A430;
  font-weight: 600;
}
.tips-grid li strong { color: #2A3340; font-weight: 600; }
.tips-grid ul.tips-subs {
  list-style: none;
  margin: 4px 0 0;
  padding-left: 18px;
}
.tips-grid ul.tips-subs li {
  padding-left: 16px;
  font-size: 13px;
  margin: 2px 0;
}
.tips-grid ul.tips-subs li::before {
  content: "\2013";
  color: #9AA6BC;
  font-weight: 600;
}

.notes-box {
  margin: 0 0 24px;
  background: #F2F5FC;
  border: 1px solid #E3EAF6;
  border-radius: 16px;
  overflow: hidden;
}
.notes-head {
  width: 100%;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 12px;
  padding: 16px 22px;
  background: none;
  border: none;
  cursor: pointer;
  font-family: var(--font-body);
  text-align: left;
}
.notes-title {
  display: flex;
  align-items: center;
  gap: 8px;
  font-family: var(--font-body);
  font-size: 13px;
  letter-spacing: 0.07em;
  text-transform: uppercase;
  font-weight: 700;
  color: #3B5BD6;
}
.notes-title .notes-icon { color: #4C63D8; font-size: 15px; }
.notes-sub { text-transform: none; letter-spacing: 0; font-weight: 500; color: #8590C9; }
.notes-chevron {
  flex-shrink: 0;
  width: 15px;
  height: 15px;
  color: #9AA5B8;
  transition: transform 150ms ease;
}
.notes-head[aria-expanded="true"] .notes-chevron { transform: rotate(180deg); }
.notes-body { padding: 2px 22px 22px; }
.notes-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(270px, 1fr));
  gap: 16px;
}
/* Two-per-row layout for topics whose formulas need more width */
.notes-grid--cols2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
@media (max-width: 620px) {
  .notes-grid--cols2 { grid-template-columns: 1fr; }
}
.note-card {
  background: #FFFFFF;
  border: 1px solid #E7ECF6;
  border-radius: 12px;
  padding: 16px 18px 17px;
  box-shadow: 0 1px 2px rgba(30, 42, 68, 0.03);
}
.note-card-title {
  margin: 0 0 9px;
  font-family: var(--font-body);
  font-size: 12px;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  font-weight: 700;
  color: #3B5BD6;
}
.note-card ul { margin: 0; padding-left: 20px; }
.note-card li {
  margin: 7px 0;
  font-size: 14px;
  line-height: 1.65;
  color: #47536B;
}
.note-card li strong { color: #2A3340; font-weight: 600; }

/* --- Question-bank content: tables, part lists and network diagrams --- */
.q-block .net {
  display: block;
  margin: 10px 0 4px;
  max-width: 100%;
  height: auto;
  background: var(--paper-raised);
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
}
.q-block .svgcap {
  margin: 2px 0 8px;
  font-size: 12px;
  color: var(--ink-faint);
}
.qtable {
  margin: 8px 0 4px;
  border-collapse: collapse;
  width: 100%;
  font-size: 13px;
  color: var(--ink-soft);
}
.qtable th,
.qtable td {
  border: 1px solid var(--line);
  padding: 5px 8px;
  text-align: left;
  vertical-align: top;
}
.qtable th {
  background: var(--paper-raised);
  color: var(--ink);
  font-weight: 600;
}
ol.parts {
  margin: 8px 0 0;
  padding-left: 0;
  list-style: none;
  font-size: 14.5px;
  line-height: 1.55;
  color: var(--ink-soft);
}
ol.parts li { margin: 4px 0; }
ol.parts .plabel {
  font-weight: 600;
  color: var(--ink);
  margin-right: 4px;
}
ol.parts .marks {
  color: var(--ink-faint);
  font-size: 12px;
}
.reveal-panel .qtable,
.reveal-panel .net { margin-top: 6px; }