:root {
  --paper: #F7F5F0;
  --ink: #1F2421;
  --ink-soft: #5C6360;
  --press-blue: #2C4A73;
  --warm-brown: #8A6A45;
  --rule: #D9D5CC;
  --paper-raised: #FFFDF8;
  --radius: 6px;
  --shell-width: 1120px;
  --prose-width: 720px;
  --font-sans: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Source Han Sans SC", "Noto Sans CJK SC", system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  --font-mono: "SFMono-Regular", "Menlo", "Consolas", "Liberation Mono", monospace;
}

/* ==========================================================================
   base
   ========================================================================== */

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

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

.site-body {
  margin: 0;
  background-color: var(--paper);
  color: var(--ink);
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.75;
  font-weight: 400;
}

.site-body h1,
.site-body h2,
.site-body h3,
.site-body h4 {
  margin: 0;
  color: var(--ink);
  font-weight: 600;
  line-height: 1.35;
}

.site-body p {
  margin: 0;
}

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

.site-body img {
  display: block;
  max-width: 100%;
}

.site-body a {
  color: var(--press-blue);
  text-decoration: none;
}

.site-body a:hover,
.site-body a:focus-visible {
  text-decoration: underline;
}

.site-body table {
  border-collapse: collapse;
  width: 100%;
}

.site-body strong {
  font-weight: 600;
}

.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  margin: -1px;
  padding: 0;
  border: 0;
  overflow: hidden;
  clip: rect(0 0 0 0);
  clip-path: inset(50%);
  white-space: nowrap;
}

.site-body :focus-visible {
  outline: 2px solid var(--press-blue);
  outline-offset: 2px;
}

/* ==========================================================================
   layout
   ========================================================================== */

.site-header {
  border-bottom: 1px solid var(--rule);
  background-color: var(--paper-raised);
}

.header-inner {
  max-width: var(--shell-width);
  margin: 0 auto;
  padding: 14px 24px;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 12px 24px;
}

.site-brand {
  display: flex;
  flex-direction: column;
  gap: 2px;
  color: var(--ink);
  text-decoration: none;
}

.site-brand:hover,
.site-brand:focus-visible {
  text-decoration: none;
}

.site-brand .brand-name {
  font-size: 20px;
  font-weight: 600;
  line-height: 1.2;
}

.site-brand .brand-slogan {
  color: var(--ink-soft);
  font-size: 12.5px;
  line-height: 1.4;
}

.site-nav {
  flex: 1 1 auto;
  display: flex;
  justify-content: flex-end;
}

.nav-list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 4px 20px;
}

.nav-list li {
  display: flex;
}

.nav-list a {
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  padding: 4px 2px;
  color: var(--ink);
  font-size: 15px;
  line-height: 1.4;
  border-bottom: 2px solid transparent;
}

.nav-list a:hover,
.nav-list a:focus-visible {
  color: var(--press-blue);
  border-bottom-color: var(--rule);
  text-decoration: none;
}

.nav-list a.is-current {
  color: var(--press-blue);
  font-weight: 600;
  border-bottom-color: var(--press-blue);
}

.nav-toggle {
  display: none;
  width: 44px;
  height: 44px;
  padding: 10px;
  border: 1px solid var(--rule);
  border-radius: var(--radius);
  background-color: var(--paper);
  cursor: pointer;
  flex-direction: column;
  justify-content: space-between;
  align-items: stretch;
}

.nav-toggle-bar {
  display: block;
  height: 2px;
  background-color: var(--ink);
}

.site-main {
  max-width: var(--shell-width);
  margin: 0 auto;
  padding: 0 24px;
}

.inner-main {
  padding-top: 20px;
  padding-bottom: 56px;
}

.site-footer {
  margin-top: 48px;
  border-top: 1px solid var(--rule);
  background-color: var(--paper-raised);
}

.footer-inner {
  max-width: var(--shell-width);
  margin: 0 auto;
  padding: 40px 24px 24px;
  display: grid;
  grid-template-columns: minmax(220px, 1.4fr) repeat(4, minmax(140px, 1fr));
  gap: 28px 32px;
}

.footer-brand .footer-brand-name {
  font-size: 18px;
  font-weight: 600;
  line-height: 1.3;
}

.footer-brand .footer-brand-note {
  margin-top: 8px;
  color: var(--ink-soft);
  font-size: 13px;
  line-height: 1.7;
}

.footer-col-title {
  font-size: 14px;
  font-weight: 600;
  color: var(--ink);
  padding-bottom: 8px;
  border-bottom: 1px solid var(--rule);
}

.footer-links {
  margin-top: 12px;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.footer-links a {
  display: inline-block;
  color: var(--ink-soft);
  font-size: 13.5px;
  line-height: 1.6;
}

.footer-links a:hover,
.footer-links a:focus-visible {
  color: var(--press-blue);
}

.footer-copy {
  max-width: var(--shell-width);
  margin: 0 auto;
  padding: 16px 24px 32px;
  border-top: 1px solid var(--rule);
  color: var(--ink-soft);
  font-size: 12.5px;
  line-height: 1.7;
}

/* 内页统一骨架：面包屑、页面标题区、主体布局 */

.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  padding: 4px 0 14px;
  color: var(--ink-soft);
  font-size: 13px;
  line-height: 1.6;
}

.breadcrumb a {
  color: var(--ink-soft);
}

.breadcrumb a:hover,
.breadcrumb a:focus-visible {
  color: var(--press-blue);
}

.breadcrumb-sep {
  color: var(--rule);
}

.breadcrumb-current {
  color: var(--ink);
}

.page-header {
  max-width: var(--prose-width);
  padding-bottom: 24px;
  margin-bottom: 28px;
  border-bottom: 1px solid var(--rule);
}

.page-title {
  font-size: 32px;
  font-weight: 600;
  line-height: 1.3;
}

.page-description {
  margin-top: 12px;
  color: var(--ink-soft);
  font-size: 15px;
  line-height: 1.8;
}

.page-layout {
  display: grid;
  gap: 40px;
}

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

.page-layout.layout-main-aside {
  grid-template-columns: minmax(0, 1fr) 280px;
}

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

.content-column,
.content-main,
.channel-content,
.main-column {
  min-width: 0;
}

/* ==========================================================================
   components
   ========================================================================== */

.btn,
.btn-primary,
.btn-ghost {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 44px;
  padding: 10px 20px;
  border-radius: var(--radius);
  font-size: 15px;
  line-height: 1.4;
  text-align: center;
}

.btn-primary {
  border: 1px solid var(--press-blue);
  background-color: var(--press-blue);
  color: #FFFFFF;
}

.btn-primary:hover,
.btn-primary:focus-visible {
  background-color: #233B5C;
  border-color: #233B5C;
  color: #FFFFFF;
  text-decoration: none;
}

.btn-ghost {
  border: 1px solid var(--rule);
  background-color: transparent;
  color: var(--press-blue);
}

.btn-ghost:hover,
.btn-ghost:focus-visible {
  border-color: var(--press-blue);
  text-decoration: none;
}

.text-link {
  color: var(--press-blue);
  font-size: 14px;
  font-weight: 600;
  border-bottom: 1px solid var(--rule);
  padding-bottom: 2px;
}

.text-link:hover,
.text-link:focus-visible {
  border-bottom-color: var(--press-blue);
  text-decoration: none;
}

/* 侧栏与分类树 */

.sidebar,
.channel-tree {
  min-width: 0;
  font-size: 14px;
}

.sidebar-block,
.tree-group {
  padding-bottom: 18px;
  margin-bottom: 18px;
  border-bottom: 1px solid var(--rule);
}

.sidebar-block:last-child,
.tree-group:last-child {
  border-bottom: 0;
  margin-bottom: 0;
}

.sidebar-title,
.tree-title {
  font-size: 15px;
  font-weight: 600;
  color: var(--ink);
  margin-bottom: 10px;
}

.tree-group-name,
.tree-group-title {
  font-size: 13px;
  font-weight: 600;
  color: var(--warm-brown);
  margin-bottom: 8px;
}

.sidebar-list,
.tree-list {
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.sidebar-list a,
.tree-list a {
  display: block;
  padding: 6px 0;
  color: var(--ink-soft);
  font-size: 13.5px;
  line-height: 1.6;
}

.sidebar-list a:hover,
.sidebar-list a:focus-visible,
.tree-list a:hover,
.tree-list a:focus-visible {
  color: var(--press-blue);
}

.sidebar-note {
  margin-top: 14px;
  color: var(--ink-soft);
  font-size: 13px;
  line-height: 1.7;
}

.sidebar-toggle {
  display: none;
  width: 100%;
  min-height: 44px;
  padding: 10px 14px;
  margin-bottom: 14px;
  border: 1px solid var(--rule);
  border-radius: var(--radius);
  background-color: var(--paper-raised);
  color: var(--ink);
  font-family: inherit;
  font-size: 14px;
  text-align: left;
  cursor: pointer;
}

.sidebar-toggle::after {
  content: "▾";
  float: right;
  color: var(--ink-soft);
}

.sidebar-toggle[aria-expanded="true"]::after {
  content: "▴";
}

/* 通用 section 结构 */

.home-section,
.section,
.channel-overview,
.channel-method,
.channel-topic-map,
.records-section,
.records-guide,
.records-map,
.guide-steps,
.guide-fields,
.guide-faq,
.related-entry,
.related-section {
  padding-bottom: 40px;
  margin-bottom: 40px;
  border-bottom: 1px solid var(--rule);
}

.home-section:last-child,
.section:last-child,
.records-map:last-child,
.related-entry:last-child,
.related-section:last-child {
  border-bottom: 0;
  margin-bottom: 0;
}

.section-head {
  max-width: var(--prose-width);
  margin-bottom: 24px;
}

.section-title,
.channel-overview h2,
.channel-method h2,
.channel-topic-map h2 {
  font-size: 22px;
  font-weight: 600;
  line-height: 1.4;
}

.section-desc,
.section-lead,
.section-intro,
.section-note {
  margin-top: 10px;
  color: var(--ink-soft);
  font-size: 14.5px;
  line-height: 1.8;
}

.section-more {
  margin-top: 20px;
}

.sub-title {
  margin-top: 24px;
  font-size: 17px;
  font-weight: 600;
}

/* 表格与对照列表 */

.field-table,
.map-table,
.cross-table {
  width: 100%;
  font-size: 14.5px;
}

.field-table th,
.field-table td,
.map-table th,
.map-table td,
.cross-table th,
.cross-table td {
  padding: 12px 14px;
  border-bottom: 1px solid var(--rule);
  text-align: left;
  vertical-align: top;
  line-height: 1.7;
}

.field-table thead th,
.map-table thead th,
.cross-table thead th {
  background-color: var(--paper-raised);
  font-weight: 600;
  color: var(--ink);
  border-bottom: 1px solid var(--ink-soft);
}

.field-table tbody th,
.map-table tbody th,
.cross-table tbody th {
  font-weight: 600;
  color: var(--ink);
}

.field-table tbody td,
.map-table tbody td,
.cross-table tbody td {
  color: var(--ink-soft);
}

.field-table-caption,
.map-table-caption,
.map-caption,
.cross-table caption {
  caption-side: top;
  text-align: left;
  padding-bottom: 10px;
  color: var(--ink-soft);
  font-size: 13px;
}

.map-table-wrap {
  overflow-x: auto;
}

/* 图片容器 */

.hero-figure,
.topic-cover,
.channel-figure,
.guide-figure,
.content-figure,
.records-figure {
  margin: 0;
  overflow: hidden;
  border: 1px solid var(--rule);
  border-radius: var(--radius);
  background-color: var(--paper-raised);
}

.hero-figure img,
.channel-figure img,
.guide-figure img,
.content-figure img,
.records-figure img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 16 / 10;
  object-fit: cover;
}

.topic-cover img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 16 / 9;
  object-fit: cover;
}

.hero-figure figcaption,
.channel-figure figcaption,
.guide-figure figcaption,
.content-figure figcaption,
.records-figure figcaption {
  padding: 10px 14px;
  border-top: 1px solid var(--rule);
  color: var(--ink-soft);
  font-size: 13px;
  line-height: 1.7;
}

/* 相关入口 */

.related-list,
.related-links {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 14px;
}

.related-item,
.related-links li {
  padding: 16px 18px;
  border: 1px solid var(--rule);
  border-radius: var(--radius);
  background-color: var(--paper-raised);
}

.related-item a,
.related-links a {
  display: inline-block;
  font-size: 15px;
  font-weight: 600;
  line-height: 1.5;
}

.related-desc {
  display: block;
  margin-top: 8px;
  color: var(--ink-soft);
  font-size: 13.5px;
  line-height: 1.7;
}

/* ==========================================================================
   pages
   ========================================================================== */

/* --- 首页 --- */

.site-lead-bar {
  background-color: var(--ink);
  color: #E8E4DC;
  font-size: 13px;
  line-height: 1.6;
  text-align: center;
  padding: 9px 24px;
}

.home-hero {
  padding: 40px 0 36px;
  border-bottom: 1px solid var(--rule);
}

.hero-lead {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 460px);
  gap: 40px;
  align-items: start;
}

.hero-kicker {
  color: var(--warm-brown);
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0;
  margin-bottom: 12px;
}

.hero-title {
  font-size: 34px;
  font-weight: 600;
  line-height: 1.3;
}

.hero-desc {
  max-width: 560px;
  margin-top: 16px;
  color: var(--ink-soft);
  font-size: 15.5px;
  line-height: 1.85;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 26px;
}

.hero-brief-list {
  margin-top: 32px;
  border-top: 1px solid var(--rule);
}

.hero-brief-item {
  display: grid;
  grid-template-columns: 48px minmax(120px, 200px) minmax(0, 1fr);
  gap: 16px;
  align-items: baseline;
  padding: 14px 0;
  border-bottom: 1px solid var(--rule);
}

.brief-index {
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--warm-brown);
}

.brief-link {
  font-size: 15px;
  font-weight: 600;
  color: var(--ink);
}

.brief-link:hover,
.brief-link:focus-visible {
  color: var(--press-blue);
}

.brief-note {
  color: var(--ink-soft);
  font-size: 14px;
  line-height: 1.7;
}

.home-channels .channel-overview-list {
  border-top: 1px solid var(--rule);
}

.channel-overview-row {
  display: grid;
  grid-template-columns: 56px minmax(120px, 180px) minmax(0, 1.4fr) minmax(0, 1fr) minmax(0, 1.4fr);
  gap: 16px;
  align-items: baseline;
  padding: 14px 0;
  border-bottom: 1px solid var(--rule);
}

.channel-no {
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--press-blue);
}

.channel-name {
  font-size: 15.5px;
  font-weight: 600;
  color: var(--ink);
}

.channel-field {
  color: var(--ink-soft);
  font-size: 14px;
  line-height: 1.7;
}

.topic-card-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 24px;
}

.topic-card {
  display: flex;
  flex-direction: column;
  border: 1px solid var(--rule);
  border-radius: var(--radius);
  background-color: var(--paper-raised);
  overflow: hidden;
}

.topic-card .topic-cover {
  border: 0;
  border-bottom: 1px solid var(--rule);
  border-radius: 0;
}

.topic-body {
  padding: 18px 20px 20px;
}

.topic-name {
  font-size: 17px;
  font-weight: 600;
  line-height: 1.45;
}

.topic-name a {
  color: var(--ink);
}

.topic-name a:hover,
.topic-name a:focus-visible {
  color: var(--press-blue);
}

.topic-bg {
  margin-top: 10px;
  color: var(--ink-soft);
  font-size: 14px;
  line-height: 1.75;
}

.topic-scale {
  margin-top: 12px;
  padding-top: 12px;
  border-top: 1px solid var(--rule);
  color: var(--warm-brown);
  font-size: 13px;
  line-height: 1.6;
}

.fields-summary-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.1fr) minmax(0, 1fr);
  gap: 40px;
}

.col-title {
  font-size: 17px;
  font-weight: 600;
  margin-bottom: 14px;
}

.fields-col .field-table {
  font-size: 14px;
}

.boundary-list {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.boundary-list li {
  position: relative;
  padding-left: 18px;
  color: var(--ink-soft);
  font-size: 14px;
  line-height: 1.75;
}

.boundary-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 10px;
  width: 6px;
  height: 6px;
  background-color: var(--warm-brown);
  border-radius: 50%;
}

.boundary-more {
  margin-top: 18px;
}

.record-month-list {
  display: flex;
  flex-direction: column;
  gap: 28px;
}

.record-month-title {
  font-size: 16px;
  font-weight: 600;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--rule);
  color: var(--ink);
}

.record-list {
  display: flex;
  flex-direction: column;
}

.record-item {
  display: grid;
  grid-template-columns: 110px minmax(140px, 1fr) minmax(120px, 200px);
  gap: 16px;
  align-items: baseline;
  padding: 12px 0;
  border-bottom: 1px solid var(--rule);
}

.record-date {
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--warm-brown);
}

.record-target {
  font-size: 14.5px;
  color: var(--ink);
}

.record-type {
  color: var(--ink-soft);
  font-size: 13.5px;
}

.site-index-grid {
  display: grid;
  grid-template-columns: repeat(5, minmax(0, 1fr));
  gap: 20px;
}

.index-col {
  display: flex;
  flex-direction: column;
  padding: 18px;
  border: 1px solid var(--rule);
  border-radius: var(--radius);
  background-color: var(--paper-raised);
}

.index-col-title {
  font-size: 15.5px;
  font-weight: 600;
}

.index-col-note {
  flex: 1 1 auto;
  margin-top: 10px;
  color: var(--ink-soft);
  font-size: 13.5px;
  line-height: 1.7;
}

.index-col-link {
  margin-top: 14px;
  font-size: 13.5px;
  font-weight: 600;
}

/* --- 题材频道 --- */

.channel-table {
  border-top: 1px solid var(--ink-soft);
}

.channel-row {
  display: grid;
  grid-template-columns: 56px minmax(110px, 160px) minmax(0, 1.3fr) minmax(0, 1fr) minmax(0, 1.3fr);
  gap: 16px;
  align-items: baseline;
  padding: 13px 0;
  border-bottom: 1px solid var(--rule);
}

.channel-row-head {
  border-bottom: 1px solid var(--ink-soft);
  padding: 10px 0;
}

.channel-row-head .cell {
  font-size: 13px;
  font-weight: 600;
  color: var(--ink);
}

.channel-row .cell {
  font-size: 14px;
  line-height: 1.7;
  color: var(--ink-soft);
}

.channel-row .cell-no {
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--press-blue);
}

.channel-row .cell-name {
  font-size: 15px;
  font-weight: 600;
  color: var(--ink);
}

.channel-figure {
  margin-bottom: 24px;
}

.method-columns,
.map-columns {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 24px;
  margin-top: 20px;
}

.method-col h3,
.map-col h3 {
  font-size: 15.5px;
  font-weight: 600;
  margin-bottom: 10px;
}

.method-list,
.map-list {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.method-list li,
.map-list li {
  color: var(--ink-soft);
  font-size: 14px;
  line-height: 1.75;
}

.channel-method > p,
.channel-topic-map > p {
  margin-top: 12px;
  color: var(--ink-soft);
  font-size: 14.5px;
  line-height: 1.8;
}

/* --- 专题片单 --- */

.topic-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 24px;
}

.topic-index {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 12.5px;
  color: var(--warm-brown);
  margin-bottom: 6px;
}

.topic-brief {
  margin-top: 10px;
  color: var(--ink-soft);
  font-size: 14px;
  line-height: 1.75;
}

.topic-meta {
  margin-top: 12px;
  padding-top: 12px;
  border-top: 1px solid var(--rule);
  color: var(--warm-brown);
  font-size: 13px;
  line-height: 1.6;
}

.section-footnote {
  margin-top: 18px;
  color: var(--ink-soft);
  font-size: 13.5px;
  line-height: 1.8;
}

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

.order-item {
  padding: 18px;
  border: 1px solid var(--rule);
  border-radius: var(--radius);
  background-color: var(--paper-raised);
}

.order-name {
  font-size: 15.5px;
  font-weight: 600;
}

.order-desc {
  margin-top: 10px;
  color: var(--ink-soft);
  font-size: 14px;
  line-height: 1.75;
}

/* --- 浏览指引 --- */

.step-list {
  display: flex;
  flex-direction: column;
  gap: 0;
  border-top: 1px solid var(--rule);
}

.step-item {
  display: grid;
  grid-template-columns: minmax(0, 240px) minmax(0, 1fr);
  gap: 24px;
  padding: 20px 0;
  border-bottom: 1px solid var(--rule);
}

.step-head {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.step-index {
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--press-blue);
}

.step-title {
  font-size: 16px;
  font-weight: 600;
  line-height: 1.5;
}

.step-body p {
  color: var(--ink-soft);
  font-size: 14.5px;
  line-height: 1.8;
}

.step-result {
  margin-top: 10px;
  padding-left: 14px;
  border-left: 2px solid var(--rule);
  color: var(--warm-brown);
  font-size: 13.5px;
  line-height: 1.7;
}

.guide-figure {
  margin-top: 28px;
}

.guide-faq .faq-item {
  border-bottom: 1px solid var(--rule);
}

.faq-question {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  min-height: 44px;
  padding: 14px 2px;
  font-size: 15.5px;
  font-weight: 600;
  color: var(--ink);
  cursor: pointer;
  list-style: none;
}

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

.faq-question::after {
  content: "+";
  flex: 0 0 auto;
  font-family: var(--font-mono);
  font-size: 18px;
  color: var(--press-blue);
}

.faq-item[open] .faq-question::after {
  content: "–";
}

.faq-question:hover,
.faq-question:focus-visible {
  color: var(--press-blue);
}

.faq-answer {
  padding: 0 2px 18px;
}

.faq-answer p {
  color: var(--ink-soft);
  font-size: 14.5px;
  line-height: 1.85;
}

.side-column {
  display: flex;
  flex-direction: column;
  gap: 24px;
}

.side-block {
  padding: 18px;
  border: 1px solid var(--rule);
  border-radius: var(--radius);
  background-color: var(--paper-raised);
}

.side-block-title {
  font-size: 15.5px;
  font-weight: 600;
}

.side-block-note {
  margin-top: 8px;
  color: var(--ink-soft);
  font-size: 13.5px;
  line-height: 1.75;
}

.check-list,
.prepare-list {
  display: flex;
  flex-direction: column;
  gap: 10px;
  margin-top: 14px;
}

.check-list li,
.prepare-list li {
  position: relative;
  padding-left: 18px;
  color: var(--ink-soft);
  font-size: 13.5px;
  line-height: 1.75;
}

.check-list li::before,
.prepare-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 9px;
  width: 6px;
  height: 6px;
  border: 1px solid var(--warm-brown);
  border-radius: 50%;
}

/* --- 字段说明 --- */

.field-item {
  padding: 18px 0;
  border-bottom: 1px solid var(--rule);
}

.field-item:last-child {
  border-bottom: 0;
  padding-bottom: 0;
}

.field-name {
  font-size: 16px;
  font-weight: 600;
}

.field-desc {
  margin-top: 8px;
  color: var(--ink-soft);
  font-size: 14.5px;
  line-height: 1.85;
}

.boundary-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 24px;
  margin-top: 20px;
}

.boundary-col-title {
  font-size: 15.5px;
  font-weight: 600;
  margin-bottom: 10px;
}

.boundary-col p {
  color: var(--ink-soft);
  font-size: 14px;
  line-height: 1.8;
}

/* --- 整理记录 --- */

.records-group {
  padding: 20px 0;
  border-bottom: 1px solid var(--rule);
}

.records-group:last-child {
  border-bottom: 0;
}

.records-month {
  font-size: 16.5px;
  font-weight: 600;
  padding-bottom: 10px;
  margin-bottom: 4px;
  border-bottom: 1px solid var(--rule);
}

.records-list .record-item {
  grid-template-columns: 110px minmax(140px, 1fr) minmax(110px, 180px);
}

.records-list .record-reason {
  grid-column: 2 / -1;
  color: var(--ink-soft);
  font-size: 13.5px;
  line-height: 1.75;
}

.records-figure {
  margin-bottom: 28px;
}

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

.guide-points li {
  color: var(--ink-soft);
  font-size: 14.5px;
  line-height: 1.8;
}

.guide-points strong {
  color: var(--ink);
}

/* --- 404 --- */

.error-main {
  padding-top: 56px;
  padding-bottom: 56px;
}

.error-panel {
  max-width: var(--prose-width);
  padding-bottom: 32px;
  margin-bottom: 32px;
  border-bottom: 1px solid var(--rule);
}

.error-code {
  font-family: var(--font-mono);
  font-size: 15px;
  color: var(--warm-brown);
}

.error-panel h1 {
  margin-top: 10px;
  font-size: 32px;
  font-weight: 600;
  line-height: 1.3;
}

.error-lead {
  margin-top: 14px;
  color: var(--ink-soft);
  font-size: 15px;
  line-height: 1.85;
}

.error-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 26px;
}

.error-next h2 {
  font-size: 22px;
  font-weight: 600;
}

.error-links {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 14px;
  margin-top: 20px;
}

.error-links li {
  padding: 16px 18px;
  border: 1px solid var(--rule);
  border-radius: var(--radius);
  background-color: var(--paper-raised);
}

.error-links a {
  font-size: 15px;
  font-weight: 600;
}

.error-note {
  margin-top: 20px;
  color: var(--ink-soft);
  font-size: 13.5px;
  line-height: 1.8;
}

/* ==========================================================================
   responsive
   ========================================================================== */

@media (max-width: 1024px) {
  .footer-inner {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .footer-brand {
    grid-column: 1 / -1;
  }

  .hero-lead {
    grid-template-columns: minmax(0, 1fr);
    gap: 28px;
  }

  .hero-desc {
    max-width: none;
  }

  .channel-overview-row,
  .channel-row {
    grid-template-columns: 48px minmax(100px, 150px) minmax(0, 1fr) minmax(0, 1fr);
  }

  .channel-overview-row .channel-field:last-child,
  .channel-row .cell-org {
    grid-column: 3 / -1;
  }

  .site-index-grid {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .method-columns,
  .map-columns,
  .boundary-grid,
  .order-list {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .page-layout.sidebar-left,
  .page-layout.layout-shell {
    grid-template-columns: minmax(0, 1fr);
    gap: 28px;
  }

  .page-layout.layout-main-aside {
    grid-template-columns: minmax(0, 1fr);
  }

  .sidebar,
  .channel-tree {
    padding-bottom: 20px;
    border-bottom: 1px solid var(--rule);
  }
}

@media (max-width: 720px) {
  .header-inner {
    padding: 12px 16px;
  }

  .site-main,
  .footer-inner,
  .footer-copy {
    padding-left: 16px;
    padding-right: 16px;
  }

  .nav-toggle {
    display: flex;
  }

  .site-nav {
    flex: 1 1 100%;
    justify-content: flex-start;
  }

  .nav-list {
    display: none;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    width: 100%;
    border-top: 1px solid var(--rule);
    padding-top: 8px;
  }

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

  .nav-list a {
    width: 100%;
    padding: 10px 0;
    border-bottom: 1px solid var(--rule);
  }

  .nav-list a.is-current {
    border-bottom-color: var(--press-blue);
  }

  .site-lead-bar {
    padding: 9px 16px;
    font-size: 12.5px;
  }

  .home-hero {
    padding-top: 28px;
  }

  .hero-title,
  .page-title,
  .error-panel h1 {
    font-size: 24px;
  }

  .section-title,
  .channel-overview h2,
  .channel-method h2,
  .channel-topic-map h2,
  .error-next h2 {
    font-size: 19px;
  }

  .hero-brief-item {
    grid-template-columns: 40px minmax(0, 1fr);
    gap: 6px 12px;
  }

  .hero-brief-item .brief-note {
    grid-column: 2 / -1;
  }

  .channel-overview-row,
  .channel-row {
    grid-template-columns: 40px minmax(0, 1fr);
    gap: 4px 12px;
  }

  .channel-overview-row .channel-field,
  .channel-row .cell {
    grid-column: 2 / -1;
  }

  .channel-row-head {
    display: none;
  }

  .topic-card-grid,
  .topic-grid,
  .method-columns,
  .map-columns,
  .boundary-grid,
  .order-list,
  .fields-summary-grid,
  .site-index-grid {
    grid-template-columns: minmax(0, 1fr);
  }

  .record-item,
  .records-list .record-item {
    grid-template-columns: minmax(0, 1fr);
    gap: 4px;
  }

  .records-list .record-reason {
    grid-column: auto;
  }

  .step-item {
    grid-template-columns: minmax(0, 1fr);
    gap: 10px;
  }

  .sidebar-toggle {
    display: block;
  }

  .sidebar-toggle + .sidebar-block {
    display: none;
  }

  .sidebar-toggle[aria-expanded="true"] + .sidebar-block {
    display: block;
  }

  .footer-inner {
    grid-template-columns: minmax(0, 1fr);
    gap: 24px;
    padding-top: 32px;
  }

  .field-table,
  .map-table,
  .cross-table {
    font-size: 13.5px;
  }

  .field-table th,
  .field-table td,
  .map-table th,
  .map-table td,
  .cross-table th,
  .cross-table td {
    padding: 10px 10px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .site-body * {
    transition: none !important;
    animation: none !important;
  }
}