:root {
  --ink: #1a1a1a;
  --muted: #6b7280;
  --border: #e5e7eb;
  --accent: #1a56db;
  --bg-soft: #f7f8fa;
  --sidebar-w: 250px;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Arial, sans-serif;
  color: var(--ink);
  line-height: 1.55;
  background: #ffffff;
}

/* ---------- top breadcrumb bar ---------- */
.crumbs {
  background: var(--bg-soft);
  border-bottom: 1px solid var(--border);
  padding: 10px 24px;
  font-size: 0.9rem;
}
.crumbs a { color: var(--accent); text-decoration: none; }
.crumbs a:hover { text-decoration: underline; }
.crumbs .disabled { color: #b5bac2; }

.crumbs-bottom {
  background: var(--bg-soft);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 10px 16px;
  margin-top: 36px;
}

/* ---------- home page (no sidebar) ---------- */
.container {
  max-width: 1100px;
  margin: 0 auto;
  padding: 32px 24px 80px;
}
.container h1 { font-size: 1.9rem; margin-bottom: 4px; }
.site-title-main { color: var(--ink); font-weight: 800; font-style: italic; }
.site-title-accent { color: #dc2626; font-weight: 800; font-style: italic; }
.site-disclaimer {
  font-size: 0.82rem;
  color: var(--muted);
  background: var(--bg-soft);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 10px 14px;
  margin: 8px 0 20px;
  line-height: 1.5;
}
.top-logo-link { display: block; cursor: pointer; }
.subtitle { color: var(--muted); margin-top: 4px; }

.container-narrow { max-width: 780px; }

ul.chapter-list {
  list-style: none;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
  gap: 10px;
  margin-top: 8px;
}
ul.chapter-list li a {
  display: block;
  padding: 12px 16px;
  border: 1px solid var(--border);
  border-radius: 8px;
  text-decoration: none;
  color: var(--ink);
  font-weight: 600;
  font-size: 0.92rem;
  line-height: 1.35;
  height: 100%;
}
ul.chapter-list li a:hover { border-color: var(--accent); background: var(--bg-soft); }

/* ---------- sidebar + content layout ---------- */
.layout { display: flex; align-items: flex-start; }

.sidebar {
  width: var(--sidebar-w);
  flex: 0 0 var(--sidebar-w);
  min-height: 100vh;
  background: var(--bg-soft);
  border-right: 1px solid var(--border);
  padding: 20px 16px;
}
.sidebar .home-link {
  display: block;
  font-weight: 700;
  color: var(--accent);
  text-decoration: none;
  margin-bottom: 18px;
}
.sidebar .home-link:hover { text-decoration: underline; }
.home-logo-img { max-width: 100%; max-height: 176px; display: block; margin: 0 auto 16px; padding-bottom: 12px; border-bottom: 1px solid var(--border); }
.home-logo-img-large { max-height: 180px; margin: 0 auto 12px; }
.container .home-logo-img-large { display: block; }
.sidebar-chapter {
  font-weight: 800;
  font-style: italic;
  font-size: 1.05rem;
  color: var(--ink);
  margin-bottom: 10px;
}

.sidebar-nav { margin-top: 4px; }
.sidebar-nav-summary {
  cursor: pointer;
  list-style: none;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 8px;
}
.sidebar-nav-summary::-webkit-details-marker { display: none; }
.sidebar-nav-summary .sidebar-chapter { margin-bottom: 0; }
.sidebar-nav-chevron { display: none; color: var(--muted); font-size: 0.8rem; }
.sidebar-nav-body { margin-top: 4px; }
.overview-link {
  display: block;
  padding: 8px 10px;
  margin: 4px 0 14px;
  border-radius: 6px;
  background: #e8ecf3;
  color: var(--ink);
  font-weight: 700;
  font-size: 0.95rem;
  text-decoration: none;
  border: 1px solid #d6ddea;
}
.overview-link:hover { background: #dde4f0; }
.overview-link.current { background: var(--accent); color: #fff; border-color: var(--accent); }

ul.sidebar-list { list-style: none; padding: 0; margin: 0; }
ul.sidebar-list li { margin: 2px 0; }
ul.sidebar-list a {
  display: block;
  padding: 4px 8px;
  border-radius: 5px;
  color: var(--accent);
  text-decoration: none;
  font-size: 0.92rem;
}
ul.sidebar-list a:hover { background: #eef1f6; }
ul.sidebar-list li.current a {
  color: var(--ink);
  font-weight: 700;
  background: #e8ecf3;
}

.content { flex: 1 1 auto; padding: 32px 40px 80px; max-width: 900px; }
.content h1 { font-size: 1.9rem; margin-bottom: 10px; color: var(--ink); font-weight: 800; font-style: italic; }
.title-rule { border: none; border-top: 3px solid #1f2a44; margin: 6px 0 24px; }
.content h2 { font-size: 1.35rem; color: var(--ink); margin-top: 4px; }
.content h2.toc-heading { font-size: 1.1rem; color: var(--ink); margin-top: 28px; }
.toc-heading { font-size: 1.1rem; color: var(--ink); font-weight: 700; margin-top: 20px; }
.quick-revision-heading { font-size: 1.4rem; margin-top: 10px; margin-bottom: 4px; }
ul.page-list { padding-left: 20px; }
ul.page-list a { color: var(--accent); text-decoration: none; }
ul.page-list a:hover { text-decoration: underline; }

.intro { margin: 10px 0 20px; color: #374151; }
.subheading-comment {
  margin: 6px 0 20px;
  padding: 10px 14px;
  background: #eff6ff;
  border-left: 3px solid var(--accent);
  border-radius: 4px;
  color: #1e3a5f;
  font-style: italic;
  font-size: 0.92rem;
}

/* ---------- search box ---------- */
.search-box { position: relative; margin: 14px 0 18px; max-width: 420px; }
.sidebar .search-box { max-width: none; margin: 0 0 20px; }
.sidebar #site-search { font-size: 0.88rem; padding: 7px 10px; }
.sidebar .search-results { max-height: 260px; }
#site-search {
  width: 100%;
  padding: 9px 12px;
  border: 1px solid var(--border);
  border-radius: 7px;
  font-size: 0.95rem;
}
#site-search:focus { outline: none; border-color: var(--accent); }
.search-results {
  display: none;
  position: absolute;
  z-index: 20;
  top: 42px;
  left: 0;
  right: 0;
  background: #fff;
  border: 1px solid var(--border);
  border-radius: 8px;
  box-shadow: 0 8px 24px rgba(0,0,0,0.12);
  max-height: 320px;
  overflow-y: auto;
}
.search-results a {
  display: block;
  padding: 9px 12px;
  color: var(--ink);
  text-decoration: none;
  font-size: 0.9rem;
  border-bottom: 1px solid var(--border);
}
.search-results a:last-child { border-bottom: none; }
.search-results a:hover { background: var(--bg-soft); }

/* ---------- standard chapter QA blocks ---------- */
.qa-block {
  margin: 18px 0;
  padding: 16px 18px;
  border: 1px solid var(--border);
  border-radius: 8px;
}
.qa-block .prompt { margin-bottom: 10px; font-weight: 600; }
.qa-block .response { color: #1f2937; }
.qa-block .label {
  display: block;
  font-size: 0.72rem;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--muted);
  font-weight: 700;
  margin-bottom: 4px;
}
.note { margin: 10px 0; color: #374151; }

.qa-block ul, .qa-block ol,
.case-left ul, .case-left ol, .case-right ul, .case-right ol,
.drug-features ul, .drug-features ol, .drug-treatment ul, .drug-treatment ol,
.intro ul, .intro ol {
  margin: 6px 0;
  padding-left: 24px;
}
.qa-block li, .case-left li, .case-right li,
.drug-features li, .drug-treatment li, .intro li {
  margin: 2px 0;
}
.qa-block ul ul, .qa-block ol ol, .qa-block ul ol, .qa-block ol ul,
.case-left ul ul, .case-right ul ul,
.drug-features ul ul, .drug-treatment ul ul {
  margin: 2px 0;
}

/* ---------- case-list pages (Cardiology) ---------- */
.case-left { margin: 16px 0; }
.case-right {
  margin: 16px 0;
  padding-top: 16px;
  border-top: 1px solid var(--border);
  color: #1f2937;
}
.doc-image { max-width: 100%; height: auto; display: block; margin: 10px 0; border: 1px solid var(--border); }
.image-missing {
  display: block;
  margin: 10px 0;
  padding: 10px 14px;
  background: #fff7ed;
  border: 1px solid #fdba74;
  color: #9a3412;
  border-radius: 6px;
  font-size: 0.9rem;
}

/* ---------- drug-table pages (Tox Tables) ---------- */
.sub-label {
  font-size: 1.2rem;
  font-style: italic;
  font-weight: 700;
  color: var(--ink);
  margin: 26px 0 8px;
}

/* ---------- self-rating widget ---------- */
.rating {
  margin-top: 12px;
  padding-top: 10px;
  border-top: 1px dashed var(--border);
  font-size: 0.85rem;
  display: flex;
  align-items: center;
  gap: 6px;
  flex-wrap: wrap;
}
.rating-label { color: var(--muted); margin-right: 4px; }
.rate-btn {
  border: 1px solid var(--border);
  background: #fff;
  border-radius: 6px;
  padding: 4px 12px;
  font-size: 0.85rem;
  cursor: pointer;
  color: var(--ink);
}
.rate-btn:hover { border-color: var(--accent); }
.rate-btn.active { background: var(--accent); color: #fff; border-color: var(--accent); }
.rate-btn[data-rating="poor"].active { background: #dc2626; border-color: #dc2626; }
.rate-btn[data-rating="soso"].active { background: #d97706; border-color: #d97706; }
.rate-btn[data-rating="nailing"].active { background: #16a34a; border-color: #16a34a; }

/* ---------- install app promo ---------- */
.app-promo {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 16px;
  margin: 4px 0 24px;
  padding: 18px 22px;
  background: linear-gradient(135deg, #0f9d58 0%, #0b7a43 100%);
  border-radius: 12px;
  box-shadow: 0 4px 14px rgba(15,157,88,0.25);
}
.app-promo-text {
  display: flex;
  flex-direction: column;
  gap: 2px;
  color: #fff;
}
.app-promo-text strong { font-size: 1.05rem; }
.app-promo-text span { font-size: 0.85rem; opacity: 0.92; max-width: 420px; }
.install-app-btn {
  display: none;
  align-items: center;
  gap: 8px;
  padding: 13px 26px;
  font-size: 1rem;
  font-weight: 800;
  color: #0b7a43;
  background: #fff;
  border: none;
  border-radius: 999px;
  cursor: pointer;
  box-shadow: 0 2px 6px rgba(0,0,0,0.15);
  flex-shrink: 0;
  transition: transform 0.12s ease;
}
.install-app-btn:hover { transform: translateY(-1px); box-shadow: 0 4px 10px rgba(0,0,0,0.2); }
.ios-install-hint {
  display: none;
  font-size: 0.85rem;
  color: #fff;
  background: rgba(255,255,255,0.15);
  border: 1px solid rgba(255,255,255,0.3);
  border-radius: 8px;
  padding: 10px 14px;
  flex-shrink: 0;
}

.flashcard-toggle {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  margin: 10px 0 22px;
  padding: 10px 16px;
  font-size: 0.95rem;
  font-weight: 700;
  color: var(--ink);
  cursor: pointer;
  background: #fff7ed;
  border: 2px solid #fdba74;
  border-radius: 10px;
}
.flashcard-toggle .switch {
  position: relative;
  display: inline-block;
  width: 42px;
  height: 24px;
  flex-shrink: 0;
}
.flashcard-toggle .switch input { opacity: 0; width: 0; height: 0; }
.flashcard-toggle .switch-track {
  position: absolute;
  inset: 0;
  background: #d1d5db;
  border-radius: 999px;
  transition: background 0.15s;
}
.flashcard-toggle .switch-track::before {
  content: "";
  position: absolute;
  height: 18px;
  width: 18px;
  left: 3px;
  bottom: 3px;
  background: #fff;
  border-radius: 50%;
  transition: transform 0.15s;
  box-shadow: 0 1px 3px rgba(0,0,0,0.3);
}
.flashcard-toggle input:checked + .switch-track { background: #ea580c; }
.flashcard-toggle input:checked + .switch-track::before { transform: translateX(18px); }

.flashcard-hidden {
  position: relative;
  color: transparent !important;
  background: #f1f3f6;
  border-radius: 6px;
  cursor: pointer;
  user-select: none;
  min-height: 2.6em;
}
.flashcard-hidden * { color: transparent !important; }
.flashcard-hidden::after {
  content: "🔒 Click to reveal";
  position: absolute;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--muted) !important;
  font-size: 0.85rem;
  font-weight: 600;
}
/* Images are part of the answer - hide them along with the text until
   revealed, same as everything else in the block. */
.flashcard-hidden .doc-image {
  visibility: hidden;
}
.drug-features, .drug-treatment { color: #1f2937; }

a { color: var(--accent); }

.site-footer {
  text-align: center;
  padding: 24px 16px 40px;
  font-size: 0.85rem;
  color: var(--muted);
}
.site-footer a { color: var(--accent); text-decoration: none; }
.site-footer a:hover { text-decoration: underline; }
.footer-disclaimer {
  margin: 0 auto 14px;
  max-width: 520px;
  font-size: 0.8rem;
  color: var(--muted);
  line-height: 1.5;
}
.footer-donation {
  margin: 10px auto 0;
  max-width: 480px;
  font-size: 0.82rem;
  color: var(--muted);
  line-height: 1.5;
}
.footer-donation a { font-weight: 600; }
.footer-updated { margin-top: 10px; font-size: 0.78rem; color: var(--muted); opacity: 0.85; }
.footer-image { max-width: 100%; max-height: 110px; display: block; margin: 0 auto 12px; }

/* ---------- progress dashboard ---------- */
.back-link {
  display: inline-block;
  margin-bottom: 14px;
  color: var(--accent);
  text-decoration: none;
  font-size: 0.9rem;
}
.back-link:hover { text-decoration: underline; }

.progress-summary { margin: 20px 0 32px; }
.summary-card {
  display: flex;
  gap: 24px;
  flex-wrap: wrap;
  background: var(--bg-soft);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 20px 24px;
}
.summary-stat { display: flex; flex-direction: column; }
.summary-num { font-size: 1.8rem; font-weight: 800; color: var(--ink); }
.summary-label { font-size: 0.82rem; color: var(--muted); margin-top: 2px; }

.chapter-progress-row {
  margin-bottom: 16px;
  padding: 14px 16px;
  border: 1px solid var(--border);
  border-radius: 8px;
}
.chapter-progress-head {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  flex-wrap: wrap;
  gap: 6px;
  margin-bottom: 8px;
}
.chapter-progress-head a { font-weight: 700; color: var(--ink); text-decoration: none; font-size: 1.05rem; }
.chapter-progress-head a:hover { color: var(--accent); }
.chapter-progress-figures { font-size: 0.82rem; color: var(--muted); }

.progress-bar-track {
  background: #e5e7eb;
  border-radius: 999px;
  height: 10px;
  overflow: hidden;
}
.progress-bar-fill {
  background: var(--accent);
  height: 100%;
  border-radius: 999px;
}

/* ---------- nav link to the dashboard, in sidebar + home page ---------- */
.progress-link {
  display: block;
  padding: 8px 10px;
  margin: 0 0 14px;
  border-radius: 6px;
  background: #eef2f8;
  color: var(--ink);
  font-weight: 600;
  font-size: 0.9rem;
  text-decoration: none;
  border: 1px solid #d6ddea;
  text-align: center;
}
.progress-link:hover { background: #e2e8f4; }

.info-link {
  display: block;
  padding: 6px 10px;
  margin: 0 0 10px;
  border-radius: 6px;
  color: #6d28d9;
  font-weight: 600;
  font-size: 0.85rem;
  text-decoration: none;
  border: 1px solid #ddd6fe;
  background: #f5f3ff;
  text-align: center;
}
.info-link:hover { background: #ede9fe; }

.info-chip-row { display: flex; gap: 8px; flex-wrap: wrap; margin: 10px 0 6px; }
.info-chip {
  display: inline-block;
  padding: 6px 14px;
  border-radius: 999px;
  color: #6d28d9;
  font-weight: 600;
  font-size: 0.85rem;
  text-decoration: none;
  border: 1px solid #ddd6fe;
  background: #f5f3ff;
}
.info-chip:hover { background: #ede9fe; }

/* ---------- revision controls (progress.html) ---------- */
.revision-controls {
  background: var(--bg-soft);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 18px 20px;
  margin: 12px 0 28px;
}
.revision-count-label {
  display: block;
  font-size: 0.88rem;
  color: var(--ink);
  margin-bottom: 12px;
}
.revision-count-label input {
  width: 80px;
  margin-left: 8px;
  padding: 5px 8px;
  border: 1px solid var(--border);
  border-radius: 5px;
  font-size: 0.9rem;
}
.revision-buttons { display: flex; gap: 10px; flex-wrap: wrap; }
.revision-btn {
  border: none;
  border-radius: 7px;
  padding: 10px 18px;
  font-size: 0.9rem;
  font-weight: 600;
  cursor: pointer;
  color: #fff;
}
.revision-btn-weak { background: #dc2626; }
.revision-btn-weak:hover { background: #b91c1c; }
.revision-btn-new { background: var(--accent); }
.revision-btn-new:hover { background: #1544b0; }
.revision-btn-random { background: #6b7280; }
.revision-btn-random:hover { background: #4b5563; }
.revision-status { margin: 12px 0 0; font-size: 0.85rem; color: var(--muted); }

/* ---------- quiz.html ---------- */
.quiz-progress { color: var(--muted); font-size: 0.85rem; margin: 10px 0 2px; }
.quiz-location { color: var(--ink); font-size: 1.05rem; font-weight: 700; margin-bottom: 14px; }
.quiz-nav {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-top: 18px;
  gap: 12px;
  flex-wrap: wrap;
}
.quiz-nav button {
  border: 1px solid var(--border);
  background: #fff;
  border-radius: 7px;
  padding: 9px 18px;
  font-size: 0.9rem;
  cursor: pointer;
  color: var(--ink);
}
.quiz-nav button:hover:not(:disabled) { border-color: var(--accent); color: var(--accent); }
.quiz-nav button:disabled { opacity: 0.4; cursor: default; }
.quiz-source-link { font-size: 0.85rem; color: var(--accent); text-decoration: none; }
.quiz-source-link:hover { text-decoration: underline; }
.quiz-done { text-align: center; padding: 40px 20px; }

/* ---------- reset progress ---------- */
.reset-progress-block { margin-top: 32px; text-align: center; }
.progress-explainer {
  font-size: 0.82rem;
  color: var(--muted);
  background: var(--bg-soft);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 12px 16px;
  margin-top: 28px;
  line-height: 1.5;
}
.reset-progress-link {
  color: #b91c1c;
  font-size: 0.85rem;
  text-decoration: none;
}
.reset-progress-link:hover { text-decoration: underline; }

.danger-box {
  border: 1px solid #fca5a5;
  background: #fef2f2;
  border-radius: 10px;
  padding: 22px 24px;
  margin-top: 16px;
}
.danger-box p { color: #7f1d1d; margin-top: 0; }
.danger-actions { display: flex; gap: 14px; align-items: center; margin-top: 14px; }
.danger-btn {
  background: #dc2626;
  color: #fff;
  border: none;
  border-radius: 7px;
  padding: 10px 20px;
  font-size: 0.9rem;
  font-weight: 700;
  cursor: pointer;
}
.danger-btn:hover { background: #b91c1c; }
.cancel-link { color: var(--muted); font-size: 0.9rem; text-decoration: none; }
.cancel-link:hover { text-decoration: underline; }
.reset-status { margin-top: 14px; font-size: 0.88rem; color: #7f1d1d; font-weight: 600; }

/* ---------- responsive ---------- */
@media (min-width: 721px) {
  .sidebar-nav-body { display: block !important; }
}
@media (max-width: 720px) {
  .layout { flex-direction: column; }
  .sidebar {
    width: 100%;
    flex: 0 0 auto;
    min-height: auto;
    border-right: none;
    border-bottom: 1px solid var(--border);
    padding: 14px 16px;
  }
  .home-logo-img { max-height: 64px; margin-bottom: 10px; padding-bottom: 8px; }
  .sidebar-nav-chevron { display: inline-block; }
  .sidebar-nav-body { display: none; padding-top: 10px; }
  .sidebar-nav[open] .sidebar-nav-body { display: block; }
  .content { padding: 24px 18px 60px; }
  .container { padding: 24px 16px 60px; }
  ul.chapter-list { grid-template-columns: 1fr; }
  .qa-block { padding: 14px 16px; }
  .summary-card { gap: 16px; padding: 16px 18px; }
}