:root {
  color-scheme: light;
  --app-bg: #f7f4ed;
  --app-bg-2: #edf4f0;
  --app-surface: #fffdf7;
  --app-panel: rgba(255, 253, 247, 0.9);
  --app-panel-solid: #fffdf7;
  --app-ink: #14201d;
  --app-ink-2: #42524b;
  --app-ink-warm: #6f4d12;
  --app-muted: #64736d;
  --app-muted-2: #8a9690;
  --app-line: rgba(87, 109, 99, 0.2);
  --app-line-strong: rgba(39, 105, 91, 0.42);
  --app-accent: #27695b;
  --app-accent-2: #a3542e;
  --app-accent-3: #2e638f;
  --app-gold: #9d6217;
  --app-red: #9d3f35;
  --app-accent-soft: rgba(39, 105, 91, 0.105);
  --app-warm-soft: rgba(163, 84, 46, 0.085);
  --app-blue-soft: rgba(46, 99, 143, 0.09);
  --app-focus: rgba(39, 105, 91, 0.28);
  --app-shadow: 0 24px 70px rgba(30, 43, 38, 0.12);
  --app-shadow-soft: 0 10px 30px rgba(30, 43, 38, 0.075);
  --app-radius: 20px;
  --app-radius-sm: 13px;
  --app-radius-xs: 8px;
  --app-gap: 16px;
  --app-left: 312px;
  --app-right: 342px;
  --app-font-ui: ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  --app-font-display: "Iowan Old Style", "Palatino Linotype", "Source Han Serif SC", serif;
}

body {
  color: var(--app-ink);
  background:
    radial-gradient(circle at 14% 8%, rgba(39, 105, 91, 0.13), transparent 34%),
    radial-gradient(circle at 86% 6%, rgba(163, 84, 46, 0.1), transparent 32%),
    linear-gradient(90deg, rgba(190, 204, 195, 0.24) 1px, transparent 1px),
    linear-gradient(0deg, rgba(190, 204, 195, 0.18) 1px, transparent 1px),
    linear-gradient(180deg, #fffdf8 0%, var(--app-bg) 54%, var(--app-bg-2) 100%);
  background-size: 960px 520px, 820px 480px, 56px 56px, 56px 56px, auto;
  background-repeat: no-repeat, no-repeat, repeat, repeat, no-repeat;
  font-family: var(--app-font-ui);
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
}

.app {
  width: min(100%, 1520px);
  margin: 0 auto;
  padding: var(--app-gap);
}

main.app {
  min-height: 100vh;
  display: grid;
  grid-template-columns: var(--app-left) minmax(0, 1fr) var(--app-right);
  gap: var(--app-gap);
}

.app > header.panel + .layout {
  margin-top: var(--app-gap);
  display: grid;
  grid-template-columns: var(--app-left) minmax(0, 1fr);
  gap: var(--app-gap);
  align-items: start;
}

.layout {
  gap: var(--app-gap);
}

.sidebar,
.trainer,
.workspace,
.viewer,
.inspector,
.graph-shell {
  min-width: 0;
}

.sidebar,
.trainer {
  position: sticky;
  top: var(--app-gap);
  max-height: calc(100vh - (var(--app-gap) * 2));
  overflow: auto;
}

.panel,
.mission,
.hero,
.sidebar,
.graph-shell,
.inspector-panel,
header.panel {
  border: 1px solid var(--app-line);
  border-radius: var(--app-radius);
  background: var(--app-panel);
  box-shadow: var(--app-shadow);
}

.panel,
.hero,
header.panel {
  padding: 18px;
}

header.panel {
  padding: 18px;
}

.brand {
  min-height: 154px;
  padding: 22px;
  display: grid;
  align-content: end;
  gap: 8px;
  border: 1px solid var(--app-line);
  border-radius: var(--app-radius);
  background:
    linear-gradient(135deg, rgba(47, 104, 93, 0.12), transparent 52%),
    linear-gradient(180deg, rgba(255, 255, 255, 0.84), var(--app-panel));
  box-shadow: var(--app-shadow);
}

.brand h1,
h1 {
  margin: 0;
  color: var(--app-ink);
  font-size: 30px;
  line-height: 1.04;
  letter-spacing: -0.03em;
}

.brand p,
.summary,
.subtitle,
.meta,
.muted,
.caption {
  color: var(--app-muted);
}

.panel-head {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 12px;
  margin-bottom: 12px;
}

.panel-head h2,
.panel-head h3 {
  margin: 0;
  font-size: 18px;
  line-height: 1.15;
  letter-spacing: -0.02em;
}

.quick-links,
.header-nav,
.route-actions,
.context-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.header-nav {
  margin-bottom: 12px;
  padding-bottom: 12px;
  border-bottom: 1px solid var(--app-line);
}

.quick-links a,
.app-nav a,
.link-btn,
.route-link,
.route-chip,
.header-nav a,
.action-btn,
.icon-btn {
  min-height: 38px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  padding: 8px 12px;
  border: 1px solid var(--app-line);
  border-radius: var(--app-radius-sm);
  background: rgba(255, 255, 255, 0.76);
  color: var(--app-muted);
  text-decoration: none;
  font: inherit;
  font-size: 13px;
  line-height: 1.1;
  cursor: pointer;
  transition: border-color 160ms ease, background 160ms ease, color 160ms ease, box-shadow 160ms ease, transform 160ms ease;
}

.app-nav {
  padding: 8px;
  border: 1px solid var(--app-line);
  border-radius: var(--app-radius);
  background: rgba(255, 255, 255, 0.48);
  box-shadow: var(--app-shadow-soft);
}

.app-nav a {
  flex: 1 1 104px;
  color: var(--app-ink);
}

.app-nav a.active,
.header-nav a.active {
  border-color: rgba(47, 104, 93, 0.35);
  background: var(--app-accent-soft);
  color: var(--app-accent);
  font-weight: 700;
}

.route-chip.primary,
.route-link.primary,
.link-btn.primary {
  border-color: rgba(47, 104, 93, 0.45);
  background: var(--app-accent-soft);
  color: var(--app-accent);
  font-weight: 700;
}

.mobile-app-nav {
  grid-column: 1 / -1;
  display: none;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 8px;
  position: sticky;
  top: 8px;
  z-index: 20;
  margin-bottom: 0;
  background: rgba(255, 255, 252, 0.94);
}

.mobile-app-nav a {
  min-width: 0;
  width: 100%;
}

.return-home-nav {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.return-home-nav .route-link {
  width: fit-content;
}

.mobile-return-home-nav {
  grid-column: 1 / -1;
  display: none;
  position: sticky;
  top: 8px;
  z-index: 20;
  margin-bottom: 0;
  background: rgba(255, 255, 252, 0.94);
}

.quick-links a:hover,
.app-nav a:hover,
.link-btn:hover,
.route-link:hover,
.route-chip:hover,
.header-nav a:hover,
.action-btn:hover,
.icon-btn:hover,
.quick-links a:focus-visible,
.app-nav a:focus-visible,
.link-btn:focus-visible,
.route-link:focus-visible,
.route-chip:focus-visible,
.header-nav a:focus-visible,
.action-btn:focus-visible,
.icon-btn:focus-visible {
  border-color: var(--app-accent);
  background: var(--app-accent-soft);
  color: var(--app-ink);
  outline: none;
  box-shadow: 0 0 0 3px var(--app-focus);
  transform: translateY(-1px);
}

.action-btn.primary,
.mode-btn.active,
.chip-btn.active,
.choice-btn.correct {
  border-color: rgba(47, 104, 93, 0.45);
  background: var(--app-accent-soft);
  color: var(--app-accent);
}

.action-btn.danger {
  border-color: rgba(168, 77, 42, 0.35);
  background: var(--app-warm-soft);
  color: var(--app-accent-2);
}

.action-btn.hard {
  border-color: rgba(167, 135, 97, 0.45);
  background: rgba(167, 135, 97, 0.12);
  color: #8a5f1e;
}

.action-btn.easy {
  border-color: rgba(49, 95, 140, 0.32);
  background: rgba(49, 95, 140, 0.1);
  color: #315f8c;
}

.action-btn.ghost {
  min-height: 34px;
  padding-inline: 10px;
  background: transparent;
}

.mission-tools {
  margin-left: auto;
  display: inline-flex;
  gap: 8px;
  flex-wrap: wrap;
}

.control-disclosure {
  display: block;
}

.control-disclosure summary {
  min-height: 38px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 10px;
  color: var(--app-ink);
  cursor: pointer;
  list-style: none;
  font-size: 15px;
  font-weight: 700;
}

.control-disclosure summary::-webkit-details-marker {
  display: none;
}

.control-disclosure summary::after {
  content: "+";
  width: 26px;
  height: 26px;
  display: inline-grid;
  place-items: center;
  border: 1px solid var(--app-line);
  border-radius: var(--app-radius);
  color: var(--app-muted);
  background: rgba(255, 255, 255, 0.72);
}

.control-disclosure[open] summary::after {
  content: "-";
}

.control-disclosure summary .icon-btn {
  margin-left: auto;
}

.control-disclosure summary:has(.icon-btn)::after {
  display: none;
}

.control-body {
  margin-top: 12px;
  display: grid;
  gap: 12px;
}

.handoff-card {
  display: grid;
  gap: 9px;
  align-content: start;
}

.handoff-card strong,
.handoff-card span {
  display: block;
}

.handoff-card span {
  color: var(--app-muted);
  font-size: 13px;
  line-height: 1.55;
}

.handoff-card .link-btn {
  width: fit-content;
}

.practice-handoff {
  margin-top: 12px;
  padding-top: 12px;
  border-top: 1px solid var(--app-line);
}

body .control-disclosure:not([open]) {
  padding-block: 10px;
}

button,
input,
select {
  font: inherit;
}

input,
select {
  border-color: var(--app-line);
  border-radius: var(--app-radius);
}

.graph-shell,
.inspector-panel {
  min-height: 0;
  overflow: hidden;
}

.context-card,
#contextPanel {
  border: 1px solid var(--app-line);
  border-radius: var(--app-radius);
  background: rgba(255, 255, 255, 0.7);
}

.context-card,
.context-copy,
.roadmap-block {
  color: var(--app-ink);
}

.roadmap-block {
  display: grid;
  gap: 8px;
}

.roadmap-block + .roadmap-block,
.system-strip + .roadmap-block,
.system-strip + .context-actions,
.roadmap-block + .context-actions {
  margin-top: 12px;
}

.roadmap-block strong,
.roadmap-block span {
  display: block;
}

.search-box input,
.select-stack select {
  min-height: 38px;
}

/* Late shell overrides keep older prototype CSS from pulling pages apart. */
body .app {
  width: min(100%, 1520px);
  margin: 0 auto;
  padding: var(--app-gap);
}

body main.app {
  height: auto;
  min-height: 100vh;
  grid-template-columns: var(--app-left) minmax(0, 1fr) var(--app-right);
}

body.app-layout-two main.app {
  grid-template-columns: var(--app-left) minmax(0, 1fr);
}

body .sidebar,
body .trainer {
  height: auto;
  max-height: calc(100vh - (var(--app-gap) * 2));
}

body .sidebar {
  grid-template-rows: none;
  align-content: start;
  gap: var(--app-gap);
}

body .brand h1,
body h1 {
  font-size: 30px;
  line-height: 1.04;
}

body .panel,
body .hero,
body .mission,
body .sidebar,
body .graph-shell,
body .inspector-panel,
body header.panel {
  border-color: var(--app-line);
  background: var(--app-panel);
  box-shadow: var(--app-shadow);
}

body .quick-links {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

body .quick-links a {
  flex: 1 1 auto;
  min-width: 86px;
}

body .mission-actions {
  align-items: center;
}

body .graph-toolbar {
  min-height: 58px;
  padding: 10px 14px;
}

body .toolbar-controls,
body .edge-filter {
  gap: 6px;
}

body .edge-filter {
  padding: 8px 14px;
}

body #edgeFilter,
body #globalFilter {
  padding-block: 6px;
}

body .toolbar-controls button,
body .edge-filter button,
body .type-filter button {
  min-height: 34px;
  padding: 7px 10px;
  font-size: 12px;
  white-space: normal;
}

body .type-filter {
  margin-top: 10px;
}

body .search-box + .control-disclosure {
  margin-top: 10px;
}

body .search-box + .control-disclosure:not([open]) {
  padding-block: 4px;
}

body .search-results {
  scrollbar-width: thin;
}

body .search-results {
  max-height: 44vh;
}

body .summary {
  gap: 8px;
}

body .stat {
  min-height: 68px;
  padding: 10px;
}

body .stat-value {
  font-size: 24px;
}

.system-strip {
  display: grid;
  gap: 10px;
}

.system-step {
  position: relative;
  display: grid;
  grid-template-columns: 28px minmax(0, 1fr);
  gap: 10px;
  align-items: start;
  padding: 11px;
  border: 1px solid var(--app-line);
  border-radius: var(--app-radius-sm);
  background: rgba(255, 255, 255, 0.64);
  transition: border-color 160ms ease, background 160ms ease, box-shadow 160ms ease, transform 160ms ease;
}

button.system-step {
  width: 100%;
  color: inherit;
  font: inherit;
  text-align: left;
  cursor: pointer;
  appearance: none;
  -webkit-appearance: none;
}

.system-step b {
  width: 28px;
  height: 28px;
  display: grid;
  place-items: center;
  border-radius: 999px;
  background: var(--app-accent-soft);
  color: var(--app-accent);
  font-size: 12px;
}

.system-step strong,
.system-step span {
  display: block;
}

.system-step span {
  margin-top: 3px;
  color: var(--app-muted);
  font-size: 12px;
  line-height: 1.45;
}

.system-step.active {
  border-color: var(--app-line-strong);
  background: var(--app-accent-soft);
  box-shadow: inset 4px 0 0 var(--app-accent), 0 8px 24px rgba(39, 105, 91, 0.08);
}

.system-step:hover {
  border-color: var(--app-line-strong);
  background: rgba(255, 255, 255, 0.82);
  transform: translateY(-1px);
}

button.system-step:focus-visible {
  outline: 3px solid var(--app-focus);
  outline-offset: 2px;
}

.system-note {
  padding: 12px 14px;
  border: 1px solid rgba(49, 95, 140, 0.16);
  border-radius: var(--app-radius-sm);
  background: var(--app-blue-soft);
  color: var(--app-muted);
  line-height: 1.6;
}

.section-kicker,
.mission-kicker,
.context-kicker {
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

body .panel,
body .hero,
body .mission,
body .sidebar,
body .graph-shell,
body .inspector-panel,
body header.panel,
body .brand {
  backdrop-filter: blur(14px);
}

body .empty {
  border-radius: var(--app-radius-sm);
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    scroll-behavior: auto !important;
    transition-duration: 0.01ms !important;
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
  }
}

/* 全局焦点兜底（零特异性，页面已有样式优先） */
:where(button, a, input, select, textarea, summary, [tabindex]):focus-visible {
  outline: none;
  border-color: var(--app-accent);
  box-shadow: 0 0 0 3px var(--app-focus);
}

/* 屏幕阅读器通告区（视觉隐藏） */
.sr-live {
  position: absolute;
  width: 1px;
  height: 1px;
  margin: -1px;
  padding: 0;
  overflow: hidden;
  clip: rect(0 0 0 0);
  white-space: nowrap;
  border: 0;
}

@media (max-width: 1180px) {
  body main.app {
    grid-template-columns: minmax(240px, 0.36fr) minmax(0, 1fr);
  }

  body .trainer,
  body .inspector {
    grid-column: 1 / -1;
  }
}

@media (max-width: 860px) {
  .mobile-app-nav {
    display: grid;
  }

  body main.app {
    grid-template-columns: 1fr;
    padding: 10px;
  }

  body .sidebar,
  body .trainer {
    position: static;
    max-height: none;
  }

  body .sidebar .quick-links {
    display: none;
  }

  body .brand {
    min-height: 120px;
  }
}

body .graph-mode-filter {
  border-top: 1px solid rgba(216, 222, 213, 0.7);
}

@media (min-width: 821px) {
  body #edgeFilter,
  body #globalFilter {
    position: absolute;
    width: 1px;
    height: 1px;
    overflow: hidden;
    clip: rect(0 0 0 0);
    white-space: nowrap;
  }

  body .graph-shell {
    position: relative;
  }
}

@media (max-width: 1180px) {
  main.app,
  body main.app {
    grid-template-columns: var(--app-left) minmax(0, 1fr);
  }

  .trainer,
  .inspector {
    position: static;
    max-height: none;
    grid-column: 1 / -1;
  }
}

@media (max-width: 820px) {
  .app,
  main.app,
  body .app,
  body main.app {
    width: 100%;
    padding: 10px;
  }

  main.app,
  body main.app,
  body.app-layout-two main.app,
  .layout,
  body .layout {
    grid-template-columns: 1fr;
  }

  .app > header.panel + .layout,
  body .app > header.panel + .layout {
    grid-template-columns: 1fr;
  }

  .sidebar,
  .trainer {
    position: static;
    max-height: none;
  }

  .brand {
    min-height: auto;
  }

  body .workspace,
  body .graph-shell,
  body .viewer {
    order: 1;
  }

  body .sidebar {
    order: 2;
  }

  body .trainer,
  body .inspector {
    order: 3;
  }

  body .brand {
    display: none;
  }

  body .app-nav {
    position: sticky;
    top: 8px;
    z-index: 20;
    margin-bottom: 10px;
    padding-inline: 8px 14px;
    overflow: visible;
    flex-wrap: wrap;
    background: rgba(255, 255, 252, 0.94);
    scroll-padding-inline: 8px 14px;
  }

  body .sidebar > .app-nav {
    display: none;
  }

  body .sidebar > .return-home-nav {
    display: none;
  }

  body .mobile-app-nav {
    order: 0;
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  body .mobile-return-home-nav {
    order: 0;
    display: flex;
  }

  body .mobile-app-nav::before {
    content: none;
  }

  body .app-nav a {
    min-width: 0;
    white-space: nowrap;
  }

  body.memory-page .workspace {
    order: 1;
  }

  body.memory-page .trainer {
    order: 2;
  }

  body.memory-page .sidebar {
    order: 3;
  }

  body.knowledge-graph-page .graph-shell {
    order: 1;
  }

  body.knowledge-graph-page .inspector {
    order: 2;
  }

  body.knowledge-graph-page .sidebar {
    order: 3;
  }

  body.knowledge-graph-page .inspector-panel {
    height: auto;
  }

  body.knowledge-graph-page .three-stage,
  body.knowledge-graph-page .knowledge-svg,
  body.knowledge-graph-page .learning-route-wrap {
    min-height: 430px;
  }

  body .mission {
    min-height: 320px;
  }

  body .mission-word {
    font-size: 64px;
  }

  body .mission-tools {
    width: 100%;
    margin-left: 0;
  }

  body .choices {
    gap: 8px;
  }

  body .choice-btn {
    min-height: 58px;
    padding: 10px 12px;
  }
}