:root {
  color-scheme: light;
  --paper: #fcfdff;
  --surface: #ffffff;
  --rail: #edf4f7;
  --ink: #17212b;
  --muted: #52606d;
  --faint: #cbd5e1;
  --forest: #008c72;
  --water: #1769e0;
  --vermilion: #e24736;
  --coral: #ff6b4a;
  --gold: #865900;
  --mist: #eaf2ff;
  --mint: #e7f7f3;
  --blush: #fff0ed;
  --serif: "Noto Serif", "Noto Serif CJK SC", "Source Han Serif SC", "Songti SC",
    "Yu Mincho", serif;
  --sans: "Noto Sans", "Noto Sans CJK SC", "Source Han Sans SC", "Hiragino Sans",
    system-ui, sans-serif;
}

* {
  box-sizing: border-box;
  letter-spacing: 0;
}

html {
  scroll-behavior: smooth;
  scroll-padding-top: 88px;
}

body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: var(--sans);
  font-size: 16px;
  line-height: 1.55;
}

button,
select,
input {
  font: inherit;
}

button,
a,
select,
label {
  -webkit-tap-highlight-color: transparent;
}

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

.skip-link {
  position: fixed;
  z-index: 100;
  top: 8px;
  left: 8px;
  padding: 8px 12px;
  background: var(--ink);
  color: white;
  transform: translateY(-160%);
}

.skip-link:focus {
  transform: translateY(0);
}

.app-header {
  position: sticky;
  z-index: 30;
  top: 0;
  display: grid;
  grid-template-columns: 220px minmax(180px, 1fr) auto;
  min-height: 68px;
  border-bottom: 1px solid var(--faint);
  background: var(--surface);
}

.brand,
.destination-mark,
.reader-controls {
  min-width: 0;
  padding: 11px 20px;
}

.brand {
  display: flex;
  flex-direction: column;
  justify-content: center;
  border-right: 1px solid var(--faint);
  color: var(--ink);
  line-height: 1.15;
  text-decoration: none;
}

.brand strong {
  font-size: 18px;
}

.brand span,
.destination-mark span {
  margin-top: 3px;
  color: var(--muted);
  font-size: 11px;
}

.destination-mark {
  display: flex;
  flex-direction: column;
  justify-content: center;
  line-height: 1.2;
}

.destination-picker {
  display: block;
  margin-top: 4px;
}

.destination-picker select {
  width: min(100%, 370px);
  height: 30px;
  border: 1px solid #aebdca;
  border-radius: 4px;
  background: var(--surface);
  color: var(--ink);
  font: inherit;
  font-size: 13px;
  font-weight: 700;
}

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  clip-path: inset(50%);
  white-space: nowrap;
}

.reader-controls {
  display: flex;
  align-items: center;
  justify-content: flex-end;
  gap: 12px;
}

.segmented {
  display: grid;
  grid-template-columns: repeat(4, 42px);
  overflow: hidden;
  border: 1px solid #aebdca;
  border-radius: 6px;
  background: var(--surface);
}

.segmented button {
  width: 42px;
  height: 34px;
  border: 0;
  border-right: 1px solid var(--faint);
  background: transparent;
  color: var(--muted);
  cursor: pointer;
  font-size: 13px;
  font-weight: 700;
}

.segmented button:last-child {
  border-right: 0;
}

.segmented button[aria-pressed="true"] {
  background: var(--water);
  color: white;
}

.segmented button:focus-visible,
.map-tools button:focus-visible,
.utility-link:focus-visible,
.destination-picker select:focus-visible,
.ruby-switch:has(input:focus-visible) {
  outline: 3px solid rgba(23, 105, 224, 0.32);
  outline-offset: 2px;
}

.ruby-switch {
  display: flex;
  align-items: center;
  gap: 7px;
  min-height: 34px;
  color: var(--muted);
  cursor: pointer;
  font-size: 12px;
  font-weight: 700;
}

.ruby-switch input {
  position: absolute;
  width: 1px;
  height: 1px;
  opacity: 0;
}

.switch-track {
  position: relative;
  display: inline-block;
  width: 34px;
  height: 20px;
  border: 1px solid #aab4ae;
  border-radius: 10px;
  background: #c9d0cc;
}

.switch-track span {
  position: absolute;
  top: 2px;
  left: 2px;
  width: 14px;
  height: 14px;
  border-radius: 50%;
  background: white;
  transition: transform 140ms ease;
}

.ruby-switch input:checked + .switch-track {
  border-color: var(--forest);
  background: var(--forest);
}

.ruby-switch input:checked + .switch-track span {
  transform: translateX(14px);
}

.utility-link {
  display: inline-flex;
  align-items: center;
  min-height: 34px;
  color: var(--ink);
  font-size: 12px;
  font-weight: 700;
  text-decoration: none;
}

.app-shell {
  display: grid;
  grid-template-columns: 260px minmax(0, 1fr);
  min-height: calc(100vh - 68px);
}

.book-rail {
  position: sticky;
  top: 68px;
  align-self: start;
  height: calc(100vh - 68px);
  overflow-y: auto;
  border-right: 1px solid var(--faint);
  background: var(--rail);
  padding: 30px 24px 24px;
}

.rail-heading span,
.rail-label,
.rail-edition span,
.chapter-kicker,
.block-index,
.block-category,
.time-label,
.source-number,
.map-label {
  color: var(--muted);
  font-size: 11px;
  font-weight: 700;
}

.rail-heading h1 {
  margin: 12px 0 0;
  font-family: var(--serif);
  font-size: 38px;
  line-height: 1.1;
}

.rail-heading p {
  margin: 5px 0 0;
  color: var(--forest);
  font-family: var(--serif);
  font-size: 15px;
}

.chapter-outline,
.section-outline {
  margin: 28px 0 0;
  padding: 0;
  list-style: none;
}

.chapter-outline li {
  border-top: 1px solid rgba(23, 105, 224, 0.14);
}

.chapter-outline {
  margin-top: 8px;
}

.chapter-outline a,
.chapter-outline span {
  display: grid;
  grid-template-columns: 28px minmax(0, 1fr);
  gap: 8px;
  padding: 9px 0;
  color: var(--ink);
  font-size: 12px;
  line-height: 1.35;
  text-decoration: none;
}

.chapter-outline .future {
  color: #7c847f;
}

.chapter-outline .available a:hover,
.chapter-outline .available a:focus-visible {
  color: var(--forest);
}

.chapter-outline .active a {
  color: var(--vermilion);
  font-weight: 700;
}

.outline-title [data-lang] {
  display: block;
}

.rail-label {
  margin: 30px 0 0;
}

.section-outline {
  margin-top: 8px;
}

.section-outline a {
  display: grid;
  grid-template-columns: 24px minmax(0, 1fr);
  gap: 8px;
  padding: 5px 0;
  color: var(--muted);
  font-size: 12px;
  text-decoration: none;
}

.section-outline a:hover,
.section-outline a:focus-visible {
  color: var(--ink);
}

.rail-edition {
  margin-top: 30px;
  padding-top: 16px;
  border-top: 1px solid rgba(0, 140, 114, 0.22);
}

.rail-edition p {
  margin: 4px 0 0;
  color: var(--muted);
  font-size: 11px;
}

.mobile-jump {
  display: none;
}

main {
  min-width: 0;
}

.loading,
.noscript {
  padding: 80px 7vw;
  color: var(--muted);
  font-family: var(--serif);
  font-size: 18px;
}

.chapter-masthead,
.reading-block,
.sources,
.book-footer {
  width: min(1120px, calc(100% - 80px));
  margin: 0 auto;
}

.chapter-masthead {
  min-height: 440px;
  padding: 72px 0 64px;
  border-bottom: 1px solid var(--faint);
}

.chapter-kicker {
  display: inline-flex;
  align-items: center;
  gap: 9px;
  color: var(--vermilion);
}

.chapter-kicker::before {
  width: 10px;
  height: 10px;
  flex: 0 0 10px;
  border-radius: 50%;
  background: var(--vermilion);
  content: "";
}

.chapter-title {
  margin: 44px 0 0;
}

.chapter-title [data-lang] {
  display: block;
}

.chapter-title [data-lang="zh"] {
  font-family: var(--serif);
  font-size: 48px;
  line-height: 1.15;
}

.chapter-title [data-lang="ja"] {
  margin-top: 16px;
  color: var(--forest);
  font-family: var(--serif);
  font-size: 27px;
  font-weight: 500;
}

.chapter-title [data-lang="en"] {
  margin-top: 12px;
  color: var(--water);
  font-family: var(--serif);
  font-size: 25px;
  font-weight: 500;
}

.chapter-deck {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 18px;
  margin-top: 46px;
  color: var(--muted);
  font-size: 12px;
}

.chapter-deck span:not(:last-child)::after {
  margin-left: 18px;
  color: var(--coral);
  content: "·";
}

.reading-block {
  padding: 54px 0 58px;
  border-bottom: 1px solid var(--faint);
}

.block-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  margin-bottom: 28px;
}

.block-meta {
  display: flex;
  align-items: center;
  gap: 14px;
}

.block-index {
  display: grid;
  width: 34px;
  height: 34px;
  flex: 0 0 34px;
  place-items: center;
  border-radius: 50%;
  background: var(--vermilion);
  color: white;
  font-size: 12px;
}

.reading-block[data-category="maps"] .block-index,
.reading-block[data-category="itineraries"] .block-index {
  background: var(--water);
}

.reading-block[data-category="cultural-context"] .block-index {
  background: var(--forest);
}

.reading-block.kind-callout {
  width: min(1168px, calc(100% - 48px));
  padding-right: 24px;
  padding-left: 30px;
  border-left: 6px solid var(--coral);
  background: var(--blush);
}

.reading-block.kind-callout .block-index {
  width: 42px;
  height: 42px;
  flex-basis: 42px;
  background: var(--coral);
  box-shadow: 0 0 0 7px rgba(255, 107, 74, 0.16);
}

.block-category {
  color: var(--forest);
}

.block-heading {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 36px;
  margin: -10px 0 26px;
  color: var(--ink);
  font-family: var(--serif);
  font-size: 15px;
  font-weight: 700;
  line-height: 1.4;
}

.block-heading span {
  min-width: 0;
}

.time-label {
  color: var(--gold);
  text-align: right;
}

.language-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 36px;
}

.language-panel {
  min-width: 0;
}

.language-label {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 16px;
  color: var(--language-color, var(--muted));
  font-size: 11px;
  font-weight: 800;
}

.language-label::before {
  width: 8px;
  height: 8px;
  flex: 0 0 8px;
  border-radius: 50%;
  background: currentColor;
  content: "";
}

.language-panel[data-lang="zh"] {
  --language-color: var(--vermilion);
}

.language-panel[data-lang="ja"] {
  --language-color: var(--forest);
}

.language-panel[data-lang="en"] {
  --language-color: var(--water);
}

.language-panel p {
  margin: 0;
  font-family: var(--serif);
  font-size: 17px;
  line-height: 2.05;
  text-wrap: pretty;
}

.language-panel[data-lang="en"] p {
  font-size: 16px;
  line-height: 1.72;
}

ruby {
  ruby-align: center;
  ruby-position: over;
}

rt {
  color: #5b6875;
  font-family: var(--sans);
  font-size: 0.52em;
  font-weight: 500;
  line-height: 1;
}

.hide-ruby rt {
  display: none;
}

.block-citations {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 7px;
  margin-top: 22px;
  color: var(--muted);
  font-size: 11px;
}

.block-citations a {
  color: var(--water);
  font-weight: 700;
  text-decoration: none;
}

.map-figure {
  margin: 46px 0 0;
  border-top: 1px solid var(--faint);
  border-bottom: 1px solid var(--faint);
  background: var(--surface);
}

.map-bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  min-height: 48px;
  padding: 7px 12px 7px 18px;
  border-bottom: 1px solid var(--faint);
}

.map-label {
  color: var(--water);
}

.map-tools {
  display: grid;
  grid-template-columns: repeat(3, 34px);
  gap: 4px;
}

.map-tools button {
  width: 34px;
  height: 34px;
  border: 1px solid #c4ccc7;
  border-radius: 4px;
  background: white;
  color: var(--ink);
  cursor: pointer;
  font-size: 18px;
  line-height: 1;
}

.map-tools button:disabled {
  color: #aab1ad;
  cursor: default;
}

.map-viewport {
  overflow: auto;
  background: var(--paper);
  overscroll-behavior: contain;
}

.map-stage {
  width: 100%;
  min-width: 720px;
}

.map-stage img {
  display: block;
  width: 100%;
  height: auto;
}

.map-caption,
.figure-caption {
  padding: 18px;
}

.caption-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 24px;
}

.caption-grid p,
.visual-rights {
  margin: 0;
  color: var(--muted);
  font-size: 14px;
  line-height: 1.65;
}

.visual-rights {
  margin-top: 14px;
  padding-top: 12px;
  border-top: 1px solid var(--faint);
  font-size: 10px;
}

.editorial-figure {
  margin: 46px 0 0;
  border-top: 1px solid var(--faint);
  border-bottom: 1px solid var(--faint);
  background: var(--surface);
}

.figure-bar {
  min-height: 48px;
  padding: 14px 18px;
  border-bottom: 1px solid var(--faint);
}

.figure-label {
  color: var(--coral);
  font-size: 11px;
  font-weight: 700;
}

.figure-image {
  display: block;
  width: 100%;
  height: auto;
  max-height: 78vh;
  object-fit: contain;
  background: var(--paper);
}

.sources {
  padding: 72px 0;
}

.sources h2 {
  margin: 0;
  font-family: var(--serif);
  font-size: 30px;
  font-weight: 600;
}

.sources-note {
  margin: 10px 0 30px;
  color: var(--muted);
  font-size: 12px;
}

.source-list {
  margin: 0;
  padding: 0;
  list-style: none;
}

.source-item {
  display: grid;
  grid-template-columns: 42px minmax(0, 1fr);
  gap: 12px;
  padding: 18px 0;
  border-top: 1px solid var(--faint);
}

.source-number {
  color: var(--vermilion);
}

.source-title {
  margin: 0;
  font-family: var(--serif);
  font-size: 15px;
  font-weight: 700;
}

.source-title a {
  overflow-wrap: anywhere;
  text-decoration-thickness: 1px;
  text-underline-offset: 3px;
}

.source-detail {
  margin: 5px 0 0;
  color: var(--muted);
  font-size: 12px;
  line-height: 1.55;
}

.book-footer {
  display: flex;
  align-items: flex-end;
  justify-content: space-between;
  min-height: 220px;
  padding: 50px 0;
  border-top: 1px solid var(--faint);
}

.book-footer strong {
  font-size: 19px;
}

.book-footer p {
  margin: 3px 0 0;
  color: var(--muted);
  font-size: 11px;
}

.book-footer a {
  font-size: 12px;
  font-weight: 700;
}

html[data-mode="zh"] [data-lang]:not([data-lang="zh"]),
html[data-mode="ja"] [data-lang]:not([data-lang="ja"]),
html[data-mode="en"] [data-lang]:not([data-lang="en"]) {
  display: none;
}

html:not([data-mode="parallel"]) .language-grid,
html:not([data-mode="parallel"]) .caption-grid,
html:not([data-mode="parallel"]) .block-heading {
  grid-template-columns: minmax(0, 780px);
}

html[data-mode="parallel"] .outline-title [data-lang]:not([data-lang="en"]),
html[data-mode="parallel"] .block-category [data-lang]:not([data-lang="en"]) {
  display: none;
}

@media (max-width: 1180px) {
  .language-grid,
  .caption-grid,
  .block-heading {
    grid-template-columns: minmax(0, 1fr);
    gap: 30px;
  }

  .block-heading {
    gap: 7px;
  }

  .language-panel p {
    max-width: 760px;
  }
}

@media (max-width: 840px) {
  html {
    scroll-padding-top: 132px;
  }

  .app-header {
    grid-template-columns: minmax(125px, 0.8fr) minmax(165px, 1.2fr);
  }

  .brand,
  .destination-mark {
    padding: 9px 14px;
  }

  .reader-controls {
    grid-column: 1 / -1;
    justify-content: flex-start;
    overflow-x: auto;
    padding: 8px 14px;
    border-top: 1px solid var(--faint);
  }

  .app-shell {
    display: block;
  }

  .book-rail {
    display: none;
  }

  .mobile-jump {
    display: grid;
    grid-template-columns: auto minmax(0, 0.8fr) auto minmax(0, 1.2fr);
    align-items: center;
    gap: 10px;
    padding: 9px 14px;
    border-bottom: 1px solid var(--faint);
    background: var(--rail);
  }

  .mobile-jump label {
    color: var(--muted);
    font-size: 11px;
    font-weight: 700;
  }

  .mobile-jump select {
    width: 100%;
    min-width: 0;
    height: 34px;
    border: 1px solid #bdc6c0;
    border-radius: 4px;
    background: white;
    color: var(--ink);
    padding: 0 8px;
    font-size: 13px;
  }

  .chapter-masthead,
  .reading-block,
  .sources,
  .book-footer {
    width: min(100% - 32px, 720px);
  }

  .chapter-masthead {
    min-height: 380px;
    padding: 52px 0;
  }

  .chapter-title [data-lang="zh"] {
    font-size: 38px;
  }

  .chapter-title [data-lang="ja"] {
    font-size: 23px;
  }

  .chapter-title [data-lang="en"] {
    font-size: 21px;
  }

  .reading-block {
    padding: 42px 0 46px;
  }

  .reading-block,
  .map-figure,
  .editorial-figure {
    scroll-margin-top: 132px;
  }

  .reading-block.kind-callout {
    width: min(100% - 16px, 752px);
    padding-right: 16px;
    padding-left: 20px;
  }

  .language-panel p {
    font-size: 17px;
    line-height: 2.08;
  }

  .language-panel[data-lang="en"] p {
    line-height: 1.72;
  }

  .map-figure,
  .editorial-figure {
    margin-right: -16px;
    margin-left: -16px;
  }

  .sources {
    padding: 56px 0;
  }
}

@media (max-width: 480px) {
  .mobile-jump {
    grid-template-columns: auto minmax(0, 1fr);
  }

  .destination-picker select {
    font-size: 12px;
  }

  .destination-mark span,
  .brand span {
    font-size: 10px;
  }

  .utility-link {
    margin-left: auto;
  }

  .chapter-title {
    margin-top: 34px;
  }

  .chapter-title [data-lang="zh"] {
    font-size: 33px;
  }

  .block-header {
    align-items: flex-start;
  }

  .block-meta {
    gap: 9px;
  }

  .language-panel p {
    font-size: 16px;
  }

  .map-stage {
    min-width: 760px;
  }

  .book-footer {
    align-items: flex-start;
    flex-direction: column;
    justify-content: flex-end;
    gap: 18px;
  }
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  .switch-track span {
    transition: none;
  }
}