/* ==========================================================================
   Base
   ========================================================================== */

*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  font-size: 16px;
  -webkit-text-size-adjust: 100%;
}

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
    "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  font-size: 16px;
  line-height: 1.6;
  color: #22262b;
  background-color: #f3f4f6;
}

img {
  max-width: 100%;
  height: auto;
  display: block;
}

a {
  color: #2b7ddb;
  text-decoration: none;
}

a:hover {
  text-decoration: underline;
}

ul,
ol {
  margin: 0;
  padding: 0;
  list-style: none;
}

h1,
h2,
h3,
h4,
h5,
h6 {
  margin: 0;
  font-weight: 700;
  line-height: 1.3;
  color: #1f344d;
}

p {
  margin: 0 0 1em;
}

figure {
  margin: 0;
}

.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0 0 0 0);
  white-space: nowrap;
  border: 0;
}

/* ==========================================================================
   Layout
   ========================================================================== */

.container,
.header-shell,
.footer-shell,
.hero-shell,
.section-shell,
.stats-shell,
.inner-shell,
.layout-shell,
.page-content,
.main-content {
  width: 100%;
  max-width: 1140px;
  margin: 0 auto;
  padding-left: 20px;
  padding-right: 20px;
}

/* ==========================================================================
   Components — Header
   ========================================================================== */

.site-header {
  background-color: #1f344d;
  border-bottom: 3px solid #f6b600;
}

.header-shell {
  display: flex;
  align-items: center;
  justify-content: space-between;
  min-height: 64px;
  padding-top: 8px;
  padding-bottom: 8px;
}

.brand-logo {
  display: inline-flex;
  align-items: baseline;
  gap: 6px;
  color: #ffffff;
  text-decoration: none;
}

.brand-logo:hover {
  text-decoration: none;
}

.brand-name {
  font-size: 24px;
  font-weight: 800;
  color: #f6b600;
  letter-spacing: 0.02em;
}

.brand-sub {
  font-size: 13px;
  color: rgba(255, 255, 255, 0.75);
  letter-spacing: 0.02em;
}

.site-nav {
  display: flex;
  align-items: center;
}

.nav-toggle {
  display: none;
  background: none;
  border: 0;
  padding: 8px;
  cursor: pointer;
  min-width: 44px;
  min-height: 44px;
  align-items: center;
  justify-content: center;
}

.nav-toggle-icon {
  display: block;
  width: 20px;
  height: 2px;
  background: #ffffff;
  position: relative;
}

.nav-toggle-icon::before,
.nav-toggle-icon::after {
  content: "";
  position: absolute;
  left: 0;
  width: 20px;
  height: 2px;
  background: #ffffff;
}

.nav-toggle-icon::before {
  top: -6px;
}

.nav-toggle-icon::after {
  top: 6px;
}

.nav-list {
  display: flex;
  align-items: center;
  gap: 4px;
}

.nav-list li a {
  display: block;
  padding: 8px 14px;
  color: rgba(255, 255, 255, 0.85);
  font-size: 15px;
  font-weight: 500;
  border-radius: 4px;
  transition: background-color 0.2s, color 0.2s;
}

.nav-list li a:hover {
  color: #ffffff;
  background-color: rgba(255, 255, 255, 0.12);
  text-decoration: none;
}

.nav-list li a.is-current {
  color: #1f344d;
  background-color: #f6b600;
  font-weight: 700;
}

/* ==========================================================================
   Components — Footer
   ========================================================================== */

.site-footer {
  background-color: #1f344d;
  color: rgba(255, 255, 255, 0.75);
  margin-top: 60px;
}

.footer-shell {
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr 1.2fr;
  gap: 32px;
  padding-top: 40px;
  padding-bottom: 32px;
}

.footer-col h3 {
  color: #ffffff;
  font-size: 15px;
  font-weight: 700;
  margin-bottom: 12px;
}

.footer-col ul li {
  margin-bottom: 8px;
}

.footer-col ul li a {
  color: rgba(255, 255, 255, 0.75);
  font-size: 14px;
}

.footer-col ul li a:hover {
  color: #f6b600;
  text-decoration: none;
}

.footer-logo {
  display: inline-block;
  font-size: 20px;
  font-weight: 800;
  color: #f6b600;
  margin-bottom: 10px;
}

.brand-col p {
  font-size: 14px;
  line-height: 1.7;
  margin-bottom: 0;
}

.footer-bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.15);
  padding-top: 16px;
  padding-bottom: 16px;
  text-align: center;
}

.footer-bottom p {
  font-size: 13px;
  color: rgba(255, 255, 255, 0.6);
  margin: 0;
}

/* ==========================================================================
   Components — Buttons & Links
   ========================================================================== */

.btn-primary,
.btn-secondary,
.btn-back {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 44px;
  padding: 10px 22px;
  border-radius: 6px;
  font-size: 15px;
  font-weight: 700;
  transition: background-color 0.2s, color 0.2s, border-color 0.2s;
}

.btn-primary {
  background-color: #f6b600;
  color: #1f344d;
  border: 2px solid #f6b600;
}

.btn-primary:hover {
  background-color: #e0a800;
  border-color: #e0a800;
  text-decoration: none;
}

.btn-secondary {
  background-color: transparent;
  color: #1f344d;
  border: 2px solid #1f344d;
}

.btn-secondary:hover {
  background-color: #1f344d;
  color: #ffffff;
  text-decoration: none;
}

.btn-back {
  background-color: #f6b600;
  color: #1f344d;
  border: 2px solid #f6b600;
}

.btn-back:hover {
  background-color: #e0a800;
  border-color: #e0a800;
  text-decoration: none;
}

.text-link {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  font-weight: 600;
  font-size: 15px;
  color: #2b7ddb;
}

.text-link::after {
  content: "→";
  transition: transform 0.2s;
}

.text-link:hover {
  text-decoration: none;
}

.text-link:hover::after {
  transform: translateX(3px);
}

/* ==========================================================================
   Components — Breadcrumb
   ========================================================================== */

.breadcrumb {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 6px;
  font-size: 14px;
  color: #6b7280;
  margin-bottom: 20px;
}

.breadcrumb a {
  color: #2b7ddb;
}

.breadcrumb a:hover {
  text-decoration: underline;
}

.breadcrumb-sep {
  color: #9ca3af;
}

.breadcrumb-current {
  color: #6b7280;
}

/* ==========================================================================
   Components — Page Header
   ========================================================================== */

.page-header {
  margin-bottom: 28px;
}

.page-title {
  font-size: 32px;
  font-weight: 800;
  color: #1f344d;
  line-height: 1.25;
  margin-bottom: 10px;
}

.page-description {
  font-size: 16px;
  color: #4b5563;
  line-height: 1.7;
  max-width: 720px;
  margin-bottom: 0;
}

/* ==========================================================================
   Components — Sidebar Layout
   ========================================================================== */

.layout-shell,
.inner-shell .page-layout {
  display: grid;
  grid-template-columns: 220px minmax(0, 1fr);
  gap: 32px;
  align-items: start;
  padding-top: 32px;
  padding-bottom: 32px;
}

.sidebar-left .layout-shell,
.sidebar-left .page-layout {
  grid-template-columns: 220px minmax(0, 1fr);
}

.sidebar {
  position: sticky;
  top: 20px;
}

.sidebar-nav h2 {
  font-size: 15px;
  font-weight: 700;
  color: #1f344d;
  margin-bottom: 12px;
  padding-bottom: 8px;
  border-bottom: 2px solid #f6b600;
}

.sidebar-nav ul li {
  margin-bottom: 2px;
}

.sidebar-nav ul li a {
  display: block;
  padding: 8px 10px;
  font-size: 14px;
  color: #4b5563;
  border-left: 3px solid transparent;
  border-radius: 0 4px 4px 0;
  transition: background-color 0.2s, border-color 0.2s, color 0.2s;
}

.sidebar-nav ul li a:hover {
  color: #1f344d;
  background-color: rgba(246, 182, 0, 0.12);
  border-left-color: #f6b600;
  text-decoration: none;
}

.sidebar-nav ul li a.is-current {
  color: #1f344d;
  background-color: rgba(246, 182, 0, 0.18);
  border-left-color: #f6b600;
  font-weight: 600;
}

/* ==========================================================================
   Components — Section Title
   ========================================================================== */

.section-title {
  font-size: 24px;
  font-weight: 800;
  color: #1f344d;
  margin-bottom: 20px;
  position: relative;
  padding-bottom: 10px;
}

.section-title::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: 0;
  width: 36px;
  height: 3px;
  background-color: #f6b600;
  border-radius: 2px;
}

/* ==========================================================================
   Components — Content Media
   ========================================================================== */

.content-media {
  margin: 20px 0;
}

.content-media img {
  width: 100%;
  height: auto;
  border-radius: 8px;
}

.content-media-inline {
  max-width: 560px;
}

.content-media figcaption {
  font-size: 13px;
  color: #6b7280;
  margin-top: 8px;
  text-align: center;
}

/* ==========================================================================
   Components — FAQ
   ========================================================================== */

.faq-group {
  display: grid;
  gap: 10px;
}

.faq-item {
  background-color: #ffffff;
  border: 1px solid #e5e7eb;
  border-radius: 8px;
  overflow: hidden;
}

.faq-item summary {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 16px 18px;
  cursor: pointer;
  font-weight: 600;
  font-size: 15px;
  color: #1f344d;
  list-style: none;
  min-height: 48px;
  transition: background-color 0.2s;
}

.faq-item summary::-webkit-details-marker {
  display: none;
}

.faq-item summary::after {
  content: "+";
  font-size: 20px;
  font-weight: 400;
  color: #f6b600;
  transition: transform 0.2s;
}

.faq-item[open] summary {
  background-color: rgba(246, 182, 0, 0.08);
}

.faq-item[open] summary::after {
  content: "−";
}

.faq-item p {
  padding: 0 18px 16px;
  margin: 0;
  font-size: 15px;
  color: #4b5563;
  line-height: 1.7;
}

/* ==========================================================================
   Components — Tags
   ========================================================================== */

.tag {
  display: inline-block;
  padding: 3px 10px;
  border-radius: 12px;
  font-size: 12px;
  font-weight: 600;
  line-height: 1.5;
}

.tag-line {
  background-color: rgba(43, 125, 219, 0.12);
  color: #2b7ddb;
}

.tag-collection {
  background-color: rgba(232, 131, 58, 0.12);
  color: #e8833a;
}

.tag-guide {
  background-color: rgba(38, 166, 91, 0.12);
  color: #26a65b;
}

.tag-site {
  background-color: rgba(122, 77, 165, 0.12);
  color: #7a4da5;
}

/* ==========================================================================
   Pages — Home
   ========================================================================== */

/* Hero Info Screen */

.hero-info-screen {
  background-color: #1f344d;
  color: #ffffff;
}

.hero-shell {
  display: grid;
  grid-template-columns: 1.1fr 0.9fr;
  gap: 40px;
  align-items: center;
  padding-top: 56px;
  padding-bottom: 56px;
}

.hero-eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-size: 14px;
  font-weight: 600;
  color: #f6b600;
  margin-bottom: 16px;
  text-transform: uppercase;
  letter-spacing: 0.04em;
}

.hero-copy h1 {
  font-size: 32px;
  font-weight: 800;
  color: #ffffff;
  line-height: 1.25;
  margin-bottom: 16px;
}

.hero-lead {
  font-size: 16px;
  line-height: 1.7;
  color: rgba(255, 255, 255, 0.8);
  margin-bottom: 24px;
}

.hero-cta {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.hero-cta .btn-primary {
  border-color: #f6b600;
}

.hero-cta .btn-secondary {
  border-color: rgba(255, 255, 255, 0.6);
  color: #ffffff;
}

.hero-cta .btn-secondary:hover {
  background-color: rgba(255, 255, 255, 0.15);
  border-color: #ffffff;
}

.hero-visual {
  position: relative;
}

.hero-figure {
  border-radius: 8px;
  overflow: hidden;
}

.hero-figure img {
  width: 100%;
  height: auto;
  aspect-ratio: 4 / 3;
  object-fit: cover;
}

.arrival-card {
  position: absolute;
  left: 16px;
  right: 16px;
  bottom: 16px;
  background-color: rgba(255, 255, 255, 0.95);
  border-radius: 8px;
  padding: 14px 16px;
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.18);
}

.arrival-title {
  font-size: 13px;
  font-weight: 700;
  color: #1f344d;
  margin-bottom: 8px;
  display: flex;
  align-items: center;
  gap: 6px;
}

.arrival-title::before {
  content: "";
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background-color: #26a65b;
}

.arrival-list li {
  display: flex;
  align-items: baseline;
  gap: 8px;
  font-size: 13px;
  color: #374151;
  padding: 3px 0;
}

.arrival-date {
  font-weight: 600;
  color: #1f344d;
  font-variant-numeric: tabular-nums;
  white-space: nowrap;
}

.arrival-link {
  display: inline-block;
  margin-top: 6px;
  font-size: 13px;
  font-weight: 600;
  color: #2b7ddb;
}

/* Route Overview */

.route-overview {
  padding: 48px 0 8px;
}

.route-list {
  display: grid;
  gap: 12px;
}

.route-item {
  display: flex;
  align-items: center;
  gap: 16px;
  background-color: #ffffff;
  border-radius: 8px;
  padding: 16px 18px;
  border-left: 5px solid;
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.06);
  transition: box-shadow 0.2s, transform 0.2s;
}

.route-item:hover {
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
  transform: translateY(-2px);
}

.route-red {
  border-left-color: #d94344;
}

.route-blue {
  border-left-color: #2b7ddb;
}

.route-green {
  border-left-color: #26a65b;
}

.route-orange {
  border-left-color: #e8833a;
}

.route-purple {
  border-left-color: #7a4da5;
}

.route-teal {
  border-left-color: #2aa3a3;
}

.route-code {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  border-radius: 6px;
  background-color: #1f344d;
  color: #f6b600;
  font-size: 14px;
  font-weight: 700;
  font-variant-numeric: tabular-nums;
  flex-shrink: 0;
}

.route-info {
  flex: 1;
  min-width: 0;
}

.route-info h3 {
  font-size: 17px;
  font-weight: 700;
  color: #1f344d;
  margin-bottom: 4px;
}

.route-stations {
  font-size: 14px;
  color: #6b7280;
  margin: 0;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.route-link {
  flex-shrink: 0;
}

/* Site Stats */

.site-stats {
  padding: 40px 0;
}

.stats-shell {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
  background-color: #1f344d;
  border-radius: 8px;
  padding: 28px 32px;
}

.stat-item {
  text-align: center;
}

.stat-num {
  display: block;
  font-size: 32px;
  font-weight: 800;
  color: #f6b600;
  font-variant-numeric: tabular-nums;
  line-height: 1.2;
}

.stat-label {
  display: block;
  font-size: 14px;
  color: rgba(255, 255, 255, 0.8);
  margin-top: 6px;
}

/* Collection Preview */

.collection-preview {
  padding: 8px 0 40px;
}

.collection-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
}

.collection-card {
  background-color: #ffffff;
  border-radius: 8px;
  overflow: hidden;
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.06);
  transition: box-shadow 0.2s, transform 0.2s;
}

.collection-card:hover {
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.1);
  transform: translateY(-2px);
}

.collection-card img {
  width: 100%;
  aspect-ratio: 16 / 9;
  object-fit: cover;
}

.collection-info {
  padding: 16px 18px 18px;
}

.collection-info h3 {
  font-size: 17px;
  font-weight: 700;
  color: #1f344d;
  margin-bottom: 8px;
}

.collection-info p {
  font-size: 14px;
  color: #6b7280;
  line-height: 1.6;
  margin-bottom: 12px;
}

/* Reading Steps */

.reading-steps {
  background-color: #ffffff;
  padding: 48px 0;
  border-top: 1px solid #e5e7eb;
  border-bottom: 1px solid #e5e7eb;
}

.steps-list {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
  counter-reset: step;
}

.step-item {
  display: flex;
  gap: 14px;
  padding: 20px;
  background-color: #f3f4f6;
  border-radius: 8px;
}

.step-num {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background-color: #1f344d;
  color: #f6b600;
  font-size: 16px;
  font-weight: 800;
  flex-shrink: 0;
  font-variant-numeric: tabular-nums;
}

.step-content h3 {
  font-size: 16px;
  font-weight: 700;
  color: #1f344d;
  margin-bottom: 6px;
}

.step-content p {
  font-size: 14px;
  color: #6b7280;
  line-height: 1.6;
  margin: 0;
}

/* Update Digest */

.update-digest {
  padding: 48px 0;
}

.timetable-list {
  display: grid;
  gap: 10px;
  margin-bottom: 20px;
}

.timetable-item {
  display: flex;
  align-items: center;
  gap: 16px;
  background-color: #ffffff;
  border-radius: 8px;
  padding: 14px 18px;
  border-left: 4px solid #f6b600;
}

.time-date {
  font-size: 14px;
  font-weight: 700;
  color: #1f344d;
  font-variant-numeric: tabular-nums;
  white-space: nowrap;
  min-width: 80px;
}

.time-content {
  flex: 1;
  font-size: 15px;
  color: #374151;
}

.time-tag {
  flex-shrink: 0;
}

/* Help & Feedback */

.help-feedback {
  padding: 0 0 48px;
}

.split-shell {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 20px;
}

.help-card,
.boundary-card {
  background-color: #ffffff;
  border-radius: 8px;
  padding: 28px;
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.06);
}

.help-card h2,
.boundary-card h2 {
  font-size: 20px;
  font-weight: 700;
  color: #1f344d;
  margin-bottom: 12px;
}

.help-card p,
.boundary-card p {
  font-size: 15px;
  color: #4b5563;
  line-height: 1.7;
  margin-bottom: 16px;
}

/* ==========================================================================
   Pages — Inner (Category, Collections, Guide, Updates, Help)
   ========================================================================== */

.inner-main {
  background-color: #f3f4f6;
}

/* Category */

.content-section {
  margin-bottom: 40px;
}

.content-section h2 {
  font-size: 22px;
  font-weight: 700;
  color: #1f344d;
  margin-bottom: 12px;
}

.content-section > p {
  font-size: 15px;
  color: #4b5563;
  line-height: 1.7;
  margin-bottom: 16px;
}

.section-media {
  margin: 20px 0;
}

.section-media img {
  width: 100%;
  height: auto;
  border-radius: 8px;
}

.section-media figcaption {
  font-size: 13px;
  color: #6b7280;
  margin-top: 8px;
  text-align: center;
}

.line-list-overview {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 12px;
  margin-top: 20px;
}

.line-item-overview {
  display: flex;
  align-items: center;
  gap: 10px;
  background-color: #ffffff;
  border-radius: 8px;
  padding: 12px 14px;
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.06);
}

.line-color {
  width: 12px;
  height: 12px;
  border-radius: 3px;
  flex-shrink: 0;
}

.hot-blood-line {
  background-color: #d94344;
}

.romance-line {
  background-color: #e8833a;
}

.mystery-line {
  background-color: #7a4da5;
}

.scifi-line {
  background-color: #2b7ddb;
}

.healing-line {
  background-color: #26a65b;
}

.comedy-line {
  background-color: #2aa3a3;
}

.line-code {
  font-size: 13px;
  font-weight: 700;
  color: #6b7280;
  font-variant-numeric: tabular-nums;
}

.line-name {
  font-size: 14px;
  font-weight: 600;
  color: #1f344d;
}

.line-detail-card {
  display: flex;
  background-color: #ffffff;
  border-radius: 8px;
  overflow: hidden;
  margin-bottom: 16px;
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.06);
}

.line-color-banner {
  width: 6px;
  flex-shrink: 0;
}

.line-detail-content {
  flex: 1;
  padding: 20px 24px;
  min-width: 0;
}

.line-detail-content h3 {
  font-size: 18px;
  font-weight: 700;
  color: #1f344d;
  margin-bottom: 8px;
}

.line-detail-content p {
  font-size: 15px;
  color: #4b5563;
  line-height: 1.7;
  margin-bottom: 12px;
}

.line-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: 12px;
}

.line-tags li {
  background-color: #f3f4f6;
  border-radius: 12px;
  padding: 4px 12px;
  font-size: 13px;
  color: #374151;
}

/* Collections */

.collection-intro,
.collection-updates {
  margin-bottom: 40px;
}

.collection-intro h2,
.collection-updates h2 {
  font-size: 22px;
  font-weight: 700;
  color: #1f344d;
  margin-bottom: 12px;
}

.collection-intro p,
.collection-updates p {
  font-size: 15px;
  color: #4b5563;
  line-height: 1.7;
  margin-bottom: 12px;
}

.collection-list {
  margin-bottom: 40px;
}

.collection-list h2 {
  font-size: 22px;
  font-weight: 700;
  color: #1f344d;
  margin-bottom: 16px;
}

.collection-list .collection-card {
  display: flex;
  gap: 20px;
  background-color: #ffffff;
  border-radius: 8px;
  overflow: hidden;
  margin-bottom: 16px;
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.06);
  transition: box-shadow 0.2s, transform 0.2s;
}

.collection-list .collection-card:hover {
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.1);
  transform: translateY(-2px);
}

.collection-media {
  width: 220px;
  flex-shrink: 0;
}

.collection-media img {
  width: 100%;
  height: 100%;
  aspect-ratio: 16 / 9;
  object-fit: cover;
}

.collection-media-plain {
  width: 220px;
  flex-shrink: 0;
  background-color: #1f344d;
  display: flex;
  align-items: center;
  justify-content: center;
}

.collection-body {
  flex: 1;
  padding: 20px 24px 20px 0;
  min-width: 0;
}

.collection-body h3 {
  font-size: 18px;
  font-weight: 700;
  color: #1f344d;
  margin-bottom: 8px;
}

.collection-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: 8px;
}

.collection-tags span {
  background-color: #f3f4f6;
  border-radius: 12px;
  padding: 3px 10px;
  font-size: 12px;
  color: #374151;
}

.collection-body p {
  font-size: 14px;
  color: #6b7280;
  line-height: 1.6;
  margin-bottom: 12px;
}

.collection-link {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  font-weight: 600;
  font-size: 14px;
  color: #2b7ddb;
}

.collection-link::after {
  content: "→";
  transition: transform 0.2s;
}

.collection-link:hover {
  text-decoration: none;
}

.collection-link:hover::after {
  transform: translateX(3px);
}

/* Guide */

.guide-intro {
  margin-bottom: 32px;
}

.guide-intro p {
  font-size: 16px;
  color: #4b5563;
  line-height: 1.7;
}

.guide-progress {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 32px;
  padding: 16px 20px;
  background-color: #ffffff;
  border-radius: 8px;
  border: 1px solid #e5e7eb;
}

.progress-step {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 32px;
  height: 32px;
  border-radius: 50%;
  background-color: #e5e7eb;
  color: #6b7280;
  font-size: 14px;
  font-weight: 700;
  font-variant-numeric: tabular-nums;
}

.progress-step.is-done {
  background-color: #26a65b;
  color: #ffffff;
}

.progress-line {
  flex: 1;
  height: 3px;
  background-color: #e5e7eb;
  border-radius: 2px;
}

.guide-steps {
  margin-bottom: 40px;
}

.guide-step {
  display: flex;
  gap: 16px;
  margin-bottom: 20px;
  background-color: #ffffff;
  border-radius: 8px;
  padding: 20px 24px;
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.06);
}

.step-number {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background-color: #1f344d;
  color: #f6b600;
  font-size: 16px;
  font-weight: 800;
  flex-shrink: 0;
  font-variant-numeric: tabular-nums;
}

.step-body {
  flex: 1;
  min-width: 0;
}

.step-body h3 {
  font-size: 17px;
  font-weight: 700;
  color: #1f344d;
  margin-bottom: 8px;
}

.step-body p {
  font-size: 15px;
  color: #4b5563;
  line-height: 1.7;
  margin-bottom: 8px;
}

.guide-figure {
  margin: 24px 0;
}

.guide-figure img {
  width: 100%;
  height: auto;
  border-radius: 8px;
}

.guide-figure figcaption {
  font-size: 13px;
  color: #6b7280;
  margin-top: 8px;
  text-align: center;
}

.guide-terms {
  margin-bottom: 40px;
}

.term-list {
  display: grid;
  gap: 12px;
}

.term-item {
  background-color: #ffffff;
  border-radius: 8px;
  padding: 16px 20px;
  border-left: 4px solid #f6b600;
}

.term-item dt {
  font-size: 16px;
  font-weight: 700;
  color: #1f344d;
  margin-bottom: 4px;
}

.term-item dd {
  font-size: 14px;
  color: #4b5563;
  line-height: 1.6;
  margin: 0;
}

.guide-related {
  margin-bottom: 40px;
}

.related-links {
  display: grid;
  gap: 8px;
}

.related-links li a {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 15px;
  color: #2b7ddb;
  font-weight: 500;
}

.related-links li a::before {
  content: "→";
  color: #f6b600;
  font-weight: 700;
}

.related-links li a:hover {
  text-decoration: underline;
}

/* Updates */

.content-media-inline {
  margin: 0 0 16px;
}

.section-desc {
  font-size: 15px;
  color: #4b5563;
  line-height: 1.7;
  margin-bottom: 16px;
}

.timeline-list {
  display: grid;
  gap: 12px;
  margin-top: 20px;
}

.timeline-item {
  display: flex;
  align-items: flex-start;
  gap: 16px;
  background-color: #ffffff;
  border-radius: 8px;
  padding: 16px 20px;
  border-left: 4px solid #f6b600;
}

.timeline-date {
  font-size: 14px;
  font-weight: 700;
  color: #1f344d;
  font-variant-numeric: tabular-nums;
  white-space: nowrap;
  min-width: 80px;
}

.timeline-content {
  flex: 1;
  font-size: 15px;
  color: #374151;
  line-height: 1.6;
}

.type-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
  margin-top: 20px;
}

.type-card {
  background-color: #ffffff;
  border-radius: 8px;
  padding: 20px;
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.06);
}

.type-card h3 {
  font-size: 16px;
  font-weight: 700;
  color: #1f344d;
  margin-bottom: 8px;
}

.type-card p {
  font-size: 14px;
  color: #6b7280;
  line-height: 1.6;
  margin-bottom: 8px;
}

.type-example {
  font-size: 13px;
  color: #9ca3af;
  font-style: italic;
}

/* Help */

.help-section {
  margin-bottom: 40px;
}

.help-section h2 {
  font-size: 22px;
  font-weight: 700;
  color: #1f344d;
  margin-bottom: 12px;
}

.section-intro {
  font-size: 15px;
  color: #4b5563;
  line-height: 1.7;
  margin-bottom: 16px;
}

/* ==========================================================================
   Pages — 404
   ========================================================================== */

.error-main {
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 60vh;
  padding: 40px 20px;
}

.error-panel {
  text-align: center;
  max-width: 480px;
  background-color: #ffffff;
  border-radius: 8px;
  padding: 40px 32px;
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.06);
}

.error-code {
  font-size: 64px;
  font-weight: 800;
  color: #f6b600;
  line-height: 1;
  margin-bottom: 16px;
  font-variant-numeric: tabular-nums;
}

.error-panel h1 {
  font-size: 24px;
  font-weight: 700;
  color: #1f344d;
  margin-bottom: 12px;
}

.error-desc {
  font-size: 15px;
  color: #6b7280;
  line-height: 1.7;
  margin-bottom: 20px;
}

/* ==========================================================================
   Responsive — Mobile (≤ 768px)
   ========================================================================== */

@media (max-width: 768px) {
  .header-shell {
    min-height: 56px;
  }

  .nav-toggle {
    display: inline-flex;
  }

  .nav-list {
    display: none;
    position: absolute;
    top: 56px;
    left: 0;
    right: 0;
    background-color: #1f344d;
    flex-direction: column;
    align-items: stretch;
    padding: 8px 16px 16px;
    gap: 2px;
    border-bottom: 3px solid #f6b600;
    box-shadow: 0 8px 16px rgba(0, 0, 0, 0.2);
    z-index: 100;
  }

  .nav-list.is-open {
    display: flex;
  }

  .nav-list li a {
    padding: 12px 14px;
    border-radius: 6px;
    min-height: 44px;
    display: flex;
    align-items: center;
  }

  .site-nav {
    position: relative;
  }

  .hero-shell {
    grid-template-columns: 1fr;
    gap: 24px;
    padding-top: 36px;
    padding-bottom: 36px;
  }

  .hero-copy h1 {
    font-size: 26px;
  }

  .hero-visual {
    order: 2;
  }

  .arrival-card {
    position: static;
    margin-top: 12px;
    box-shadow: none;
  }

  .stats-shell {
    grid-template-columns: 1fr;
    gap: 16px;
    padding: 24px;
  }

  .collection-grid {
    grid-template-columns: 1fr;
  }

  .steps-list {
    grid-template-columns: 1fr;
  }

  .split-shell {
    grid-template-columns: 1fr;
  }

  .footer-shell {
    grid-template-columns: 1fr;
    gap: 24px;
    padding-top: 32px;
  }

  .layout-shell,
  .inner-shell .page-layout {
    grid-template-columns: 1fr;
    gap: 16px;
    padding-top: 20px;
  }

  .sidebar-left .layout-shell,
  .sidebar-left .page-layout {
    grid-template-columns: 1fr;
  }

  .sidebar,
  .page-sidebar {
    position: static;
    order: 2;
  }

  .sidebar-nav ul {
    display: flex;
    flex-wrap: wrap;
    gap: 6px;
  }

  .sidebar-nav ul li {
    margin-bottom: 0;
  }

  .sidebar-nav ul li a {
    border-left: none;
    border-radius: 4px;
    background-color: #ffffff;
    padding: 8px 14px;
    box-shadow: 0 1px 2px rgba(0, 0, 0, 0.06);
  }

  .page-header {
    margin-bottom: 20px;
  }

  .page-title {
    font-size: 26px;
  }

  .line-list-overview {
    grid-template-columns: 1fr 1fr;
  }

  .collection-list .collection-card {
    flex-direction: column;
  }

  .collection-media,
  .collection-media-plain {
    width: 100%;
    aspect-ratio: 16 / 9;
  }

  .collection-body {
    padding: 16px 18px 18px;
  }

  .type-grid {
    grid-template-columns: 1fr;
  }

  .timeline-item {
    flex-direction: column;
    gap: 6px;
  }

  .timeline-date {
    min-width: 0;
  }

  .guide-step {
    flex-direction: column;
    gap: 12px;
  }

  .timetable-item {
    flex-direction: column;
    align-items: flex-start;
    gap: 6px;
  }

  .time-date {
    min-width: 0;
  }

  .route-item {
    flex-wrap: wrap;
  }

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

/* ==========================================================================
   Responsive — Small Mobile (≤ 480px)
   ========================================================================== */

@media (max-width: 480px) {
  .line-list-overview {
    grid-template-columns: 1fr;
  }

  .hero-cta {
    flex-direction: column;
    align-items: stretch;
  }

  .hero-cta .btn-primary,
  .hero-cta .btn-secondary {
    width: 100%;
  }

  .brand-sub {
    display: none;
  }

  .route-item {
    flex-direction: column;
    align-items: flex-start;
    gap: 10px;
  }

  .route-link {
    margin-left: 0;
  }

  .route-stations {
    white-space: normal;
    overflow: visible;
    text-overflow: clip;
  }
}

/* 程序验收反馈：移动端正文优先 */
@media (max-width: 768px) {
  .site-main :is(.page-content, .main-content, .content-main) {
    order: 1;
  }

  .site-main :is(aside, .sidebar) {
    order: 2;
  }
}