.study-resume-card {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  margin: 0 0 34px;
  padding: 18px 20px;
  background: color-mix(in srgb, var(--accent) 8%, var(--panel));
  border: 1px solid color-mix(in srgb, var(--accent) 34%, var(--border));
  border-left: 4px solid var(--accent);
  border-radius: var(--r-panel);
}
.study-resume-card .section-label { margin-bottom: 4px; }
.study-resume-card h2 { margin: 0; font-size: 21px; }
.study-resume-card p:not(.section-label) { margin: 5px 0 0; color: var(--text-dim); font-size: 13px; }
.study-resume-card .btn { flex: none; text-decoration: none; }

.study-hub-filters {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 7px;
  margin: -4px 0 20px;
}
.study-hub-filter {
  min-height: 34px;
  padding: 6px 11px;
  color: var(--text-muted);
  background: transparent;
  border: 1px solid var(--border);
  border-radius: 999px;
  cursor: pointer;
  font-size: 12px;
}
.study-hub-filter:hover { color: var(--text); border-color: var(--border-strong); }
.study-hub-filter[aria-pressed="true"] { color: var(--accent-bright); background: var(--panel); border-color: var(--accent); }
.study-hub-filter:focus-visible { outline: none; box-shadow: var(--focus); }
.study-module-progress { height: 3px; margin-top: 12px; overflow: hidden; background: var(--border); border-radius: 99px; }
.study-module-progress span { display: block; height: 100%; background: var(--accent); border-radius: inherit; }

.study-chapter-compass {
  width: 100%;
  position: sticky;
  top: 0;
  z-index: 24;
  display: flex;
  align-items: center;
  gap: 6px;
  margin: -38px 0 58px;
  padding: 4px;
  background: color-mix(in srgb, var(--bg-alt) 94%, transparent);
  border: 1px solid var(--border);
  border-radius: var(--r-control);
  box-shadow: 0 8px 20px color-mix(in srgb, var(--bg) 42%, transparent);
  backdrop-filter: blur(10px);
}
.study-full-page.study-chapter-view .site-head {
  position: relative;
  top: auto;
}
.study-reading-position {
  flex: none;
  min-width: 72px;
  padding: 0 5px;
  color: var(--accent-bright);
  font: 700 8.5px/1.3 "SFMono-Regular", Consolas, monospace;
  letter-spacing: .08em;
  text-transform: uppercase;
}
.study-compass-links {
  min-width: 0;
  display: flex;
  flex: 1;
  gap: 4px;
  overflow-x: auto;
  scrollbar-width: thin;
}
.study-compass-links a {
  flex: 1 0 auto;
  min-height: 28px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 3px 8px;
  color: var(--text-muted);
  text-decoration: none;
  border: 1px solid transparent;
  border-radius: var(--r-control);
  font-size: 10px;
}
.study-compass-links a:hover { color: var(--text); background: var(--panel); }
.study-compass-links a[aria-current="location"] { color: var(--accent-bright); background: var(--panel-2); border-color: var(--border-strong); }
.study-compass-links a:focus-visible { outline: none; box-shadow: var(--focus); }

.study-resume-inline {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  margin-top: 18px;
  padding: 8px 11px;
  color: var(--accent-bright);
  text-decoration: none;
  background: var(--panel);
  border: 1px solid color-mix(in srgb, var(--accent) 38%, var(--border));
  border-radius: var(--r-control);
  font-size: 12.5px;
}
.study-resume-inline:hover { border-color: var(--accent); }
.study-resume-inline:focus-visible { outline: none; box-shadow: var(--focus); }

.study-node-roadmap {
  margin-top: 18px;
  padding-top: 16px;
  border-top: 1px solid var(--border);
}
.study-node-roadmap > header {
  display: flex;
  align-items: end;
  justify-content: space-between;
  gap: 12px;
  margin-bottom: 10px;
}
.study-node-roadmap h3 { margin: 0; font-size: 16px; }
.study-node-roadmap > header span { color: var(--text-muted); font: 600 10px/1.4 "SFMono-Regular", Consolas, monospace; }
.study-node-roadmap-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 7px; }
.study-node-route {
  min-width: 0;
  min-height: 54px;
  display: block;
  padding: 9px 11px;
  color: var(--text);
  text-decoration: none;
  background: var(--bg-alt);
  border: 1px solid var(--border);
  border-radius: var(--r-control);
  font-size: 12.5px;
  line-height: 1.45;
}
.study-node-route span { display: block; margin-bottom: 3px; color: var(--accent); font: 650 9.5px/1.3 "SFMono-Regular", Consolas, monospace; letter-spacing: .08em; text-transform: uppercase; }
.study-node-route:hover { border-color: var(--accent); background: var(--panel-2); }
.study-node-route.is-current { border-color: var(--accent); background: color-mix(in srgb, var(--accent) 7%, var(--bg-alt)); }
.study-node-route:focus-visible { outline: none; box-shadow: var(--focus); }

.study-key-term-rail {
  display: grid;
  grid-template-columns: 94px minmax(0, 1fr);
  gap: 12px;
  align-items: start;
  margin: -5px 0 18px;
  padding: 12px 14px;
  background: color-mix(in srgb, var(--accent) 5%, var(--bg-alt));
  border: 1px solid color-mix(in srgb, var(--accent) 24%, var(--border));
  border-radius: var(--r-control);
}
.study-key-term-label { padding-top: 5px; color: var(--accent); font: 700 9.5px/1.4 "SFMono-Regular", Consolas, monospace; letter-spacing: .12em; text-transform: uppercase; }
.study-key-term-rail ul { display: flex; flex-wrap: wrap; gap: 7px; margin: 0; padding: 0; list-style: none; }
.study-key-term-rail li { margin: 0; padding: 5px 9px; color: var(--text); background: color-mix(in srgb, var(--accent) 11%, var(--panel)); border: 1px solid color-mix(in srgb, var(--accent) 30%, var(--border)); border-radius: 999px; font-size: 12.5px; font-weight: 650; line-height: 1.45; }

.study-node-body .body-lead { padding: 12px 14px; color: var(--text); background: var(--bg-alt); border-radius: var(--r-control); font-weight: 560; }
.study-node-body .body-caution,
.study-node-body .body-reasoning { position: relative; margin-top: 14px; padding: 28px 14px 12px; border-radius: var(--r-control); }
.study-node-body .body-caution { background: color-mix(in srgb, var(--warn) 8%, var(--bg-alt)); border-left: 3px solid var(--warn); }
.study-node-body .body-reasoning { background: color-mix(in srgb, var(--good) 7%, var(--bg-alt)); border-left: 3px solid var(--good); }
.study-node-body .body-caution::before,
.study-node-body .body-reasoning::before { position: absolute; top: 8px; left: 14px; font: 700 9px/1.2 "SFMono-Regular", Consolas, monospace; letter-spacing: .1em; text-transform: uppercase; }
.study-node-body .body-caution::before { content: "易混邊界"; color: var(--warn); }
.study-node-body .body-reasoning::before { content: "推導結果"; color: var(--good); }
.study-node-body :is(p, li) > strong { color: var(--text); text-decoration-line: underline; text-decoration-color: color-mix(in srgb, var(--accent) 58%, transparent); text-decoration-thickness: 2px; text-underline-offset: 3px; }
.study-node-body .body-caution > strong { color: var(--warn); text-decoration-color: color-mix(in srgb, var(--warn) 58%, transparent); }
.study-node-body .body-reasoning > strong { color: var(--good); text-decoration-color: color-mix(in srgb, var(--good) 58%, transparent); }
.study-full-node[data-digest-tag*="陷阱"] .study-node-core { border-left-color: var(--warn); }
.study-full-node[data-digest-tag*="陷阱"] .study-node-core span { color: var(--warn); }
.study-full-node[data-digest-tag*="影像"] .study-node-core,
.study-full-node[data-digest-tag*="計算"] .study-node-core { border-left-color: var(--good); }
.study-full-node[data-digest-tag*="影像"] .study-node-core span,
.study-full-node[data-digest-tag*="計算"] .study-node-core span { color: var(--good); }

.study-full-page .trend-arrow,
.study-full-page .trend-flat-term { display: inline-flex; align-items: center; justify-content: center; min-width: 1em; font-weight: 800; }
.study-full-page .trend-up { color: var(--trend-up); }
.study-full-page .trend-down { color: var(--trend-down); }
.study-full-page .trend-flat { color: var(--trend-flat); }
.study-full-page tbody tr:nth-child(n) td.trend-up-cell { background: color-mix(in srgb, var(--trend-up) 8%, var(--bg-alt)); }
.study-full-page tbody tr:nth-child(n) td.trend-down-cell { background: color-mix(in srgb, var(--trend-down) 8%, var(--bg-alt)); }
.study-full-page tbody tr:nth-child(n) td.trend-flat-cell { background: color-mix(in srgb, var(--trend-flat) 7%, var(--bg-alt)); }

.study-scope-reference { margin-top: 58px; }
.study-scope-reference-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 12px; }
.study-scope-group { padding: 15px 16px; background: var(--panel); border: 1px solid var(--border); border-radius: var(--r-control); }
.study-scope-group h3 { color: var(--accent-bright); font-size: 15px; }
.study-scope-group ul { display: grid; gap: 7px; margin: 0; padding: 0; list-style: none; }
.study-scope-group li { display: grid; grid-template-columns: 42px minmax(0, 1fr); gap: 9px; color: var(--text-dim); font-size: 13px; }
.study-scope-group b { color: var(--accent); font-family: "SFMono-Regular", Consolas, monospace; }

.study-full-node,
.chapter-section,
.study-digest,
.study-netter,
.study-optional-images,
.study-scope-reference { scroll-margin-top: 72px; }
html { scroll-padding-top: 72px; }

.study-real-media img,
.study-full-dialog-stage img { height: auto; }

@media (max-width: 680px) {
  .study-resume-card { display: grid; gap: 12px; padding: 16px; }
  .study-resume-card .btn { width: 100%; text-align: center; }
  .study-chapter-compass { gap: 4px; margin-top: -42px; padding: 6px; border-radius: var(--r-control); }
  .study-reading-position { min-width: 78px; padding: 0 4px; font-size: 9px; }
  .study-compass-links a { min-height: 36px; padding: 5px 9px; }
  .study-node-roadmap-grid,
  .study-scope-reference-grid { grid-template-columns: 1fr; }
  .study-key-term-rail { grid-template-columns: 1fr; gap: 6px; }
  .study-key-term-label { padding-top: 0; }
}

@media (prefers-reduced-motion: reduce) {
  .study-chapter-compass *,
  .study-resume-card * { scroll-behavior: auto !important; transition: none !important; }
}

@media print {
  .study-chapter-compass,
  .study-resume-card,
  .study-resume-inline,
  .study-hub-filters { display: none !important; }
}