:root {
  --page-bg: #f7f6f2;
  --ink: #1f2328;
  --ink-soft: #5b6470;
  --brand: #1f6f8b;
  --brand-deep: #17566d;
  --rank: #c2683a;
  --line: #e2e0d9;
  --card-bg: #ffffff;
  --card-bg-soft: #fbfaf6;
  --radius: 8px;
  --radius-sm: 5px;
  --container: 1120px;
  --shadow: 0 1px 2px rgba(31, 35, 40, 0.05);
  --font-base: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
    "Hiragino Sans GB", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
}

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

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

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

body {
  margin: 0;
  background: var(--page-bg);
  color: var(--ink);
  font-family: var(--font-base);
  font-size: 16px;
  line-height: 1.75;
  font-variant-numeric: tabular-nums;
}

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

a {
  color: var(--brand);
  text-decoration: none;
}

a:hover,
a:focus-visible {
  color: var(--brand-deep);
  text-decoration: underline;
}

h1,
h2,
h3,
p,
ul,
ol,
figure,
blockquote {
  margin: 0;
}

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

button {
  font: inherit;
  color: inherit;
}

:focus-visible {
  outline: 2px solid var(--brand);
  outline-offset: 2px;
}

/* ============================================================
   layout — 全站骨架
   ============================================================ */

.site-body {
  display: flex;
  flex-direction: column;
  min-height: 100vh;
  background: var(--page-bg);
}

.site-main {
  flex: 1 1 auto;
  width: 100%;
}

.home-main,
.inner-main {
  width: 100%;
  max-width: var(--container);
  margin: 0 auto;
  padding: 0 24px 72px;
}

.inner-main {
  padding-top: 0;
}

/* 事实说明条 */
.fact-bar {
  background: #eef0ec;
  border-bottom: 1px solid var(--line);
  color: var(--ink-soft);
  font-size: 13px;
  line-height: 1.6;
  letter-spacing: 0;
}

.fact-bar {
  padding: 8px 24px;
  max-width: var(--container);
  margin: 0 auto;
}

.fact-bar {
  max-width: none;
}

.fact-bar {
  padding-left: max(24px, calc((100vw - var(--container)) / 2 + 24px));
  padding-right: max(24px, calc((100vw - var(--container)) / 2 + 24px));
}

/* ============================================================
   layout — 页头与导航
   ============================================================ */

.site-header {
  position: sticky;
  top: 0;
  z-index: 30;
  background: rgba(247, 246, 242, 0.96);
  border-bottom: 1px solid var(--line);
  backdrop-filter: saturate(140%) blur(6px);
}

.header-inner {
  max-width: var(--container);
  margin: 0 auto;
  padding: 12px 24px;
  display: flex;
  align-items: center;
  gap: 24px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-size: 19px;
  font-weight: 700;
  color: var(--ink);
  letter-spacing: 0;
  white-space: nowrap;
}

.brand:hover,
.brand:focus-visible {
  color: var(--brand);
  text-decoration: none;
}

.brand::before {
  content: "";
  width: 10px;
  height: 20px;
  border-radius: 2px;
  background: var(--brand);
  flex: none;
}

.site-nav {
  margin-left: auto;
}

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

.nav-list li {
  display: block;
}

.nav-list a {
  display: inline-flex;
  align-items: center;
  min-height: 40px;
  padding: 0 12px;
  border-radius: var(--radius-sm);
  color: var(--ink-soft);
  font-size: 15px;
  font-weight: 500;
  white-space: nowrap;
}

.nav-list a:hover,
.nav-list a:focus-visible {
  background: #eceae3;
  color: var(--ink);
  text-decoration: none;
}

.nav-list a.is-current {
  color: var(--brand);
  font-weight: 700;
  background: #e6eff2;
}

.nav-toggle {
  display: none;
  margin-left: auto;
  width: 44px;
  height: 44px;
  padding: 0;
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
  background: var(--card-bg);
  cursor: pointer;
  position: relative;
}

.nav-toggle::before {
  content: "";
  position: absolute;
  left: 12px;
  right: 12px;
  top: 15px;
  height: 2px;
  background: var(--ink);
  box-shadow: 0 6px 0 var(--ink), 0 12px 0 var(--ink);
}

/* ============================================================
   layout — 面包屑与页面标题区
   ============================================================ */

.breadcrumb {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 6px;
  padding: 20px 0 0;
  font-size: 13px;
  color: var(--ink-soft);
}

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

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

.breadcrumb-sep {
  color: #b3b1a8;
}

.breadcrumb-current {
  color: var(--ink);
  font-weight: 600;
}

.page-header {
  padding: 14px 0 26px;
  border-bottom: 1px solid var(--line);
  margin-bottom: 32px;
}

.page-title {
  font-size: 34px;
  line-height: 1.3;
  font-weight: 700;
  color: var(--ink);
  letter-spacing: 0;
}

.page-description {
  margin-top: 12px;
  max-width: 46em;
  color: var(--ink-soft);
  font-size: 15px;
  line-height: 1.8;
}

/* ============================================================
   layout — 内页资源中心两栏
   ============================================================ */

.page-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 268px;
  gap: 40px;
  align-items: start;
}

.page-layout.sidebar-left {
  grid-template-columns: 236px minmax(0, 1fr);
}

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

/* 侧栏 */
.page-sidebar,
.page-aside,
.category-sidebar {
  min-width: 0;
  background: var(--card-bg);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 18px 16px;
  box-shadow: var(--shadow);
}

.sidebar-title,
.aside-title {
  font-size: 15px;
  font-weight: 700;
  color: var(--ink);
  padding-bottom: 10px;
  margin-bottom: 12px;
  border-bottom: 1px solid var(--line);
}

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

.sidebar-list a,
.aside-list a {
  display: flex;
  align-items: center;
  min-height: 40px;
  padding: 8px 10px;
  border-radius: var(--radius-sm);
  color: var(--ink-soft);
  font-size: 14px;
  line-height: 1.5;
}

.sidebar-list a:hover,
.sidebar-list a:focus-visible,
.aside-list a:hover,
.aside-list a:focus-visible {
  background: #eef3f5;
  color: var(--brand-deep);
  text-decoration: none;
}

.sidebar-note {
  margin-top: 14px;
  padding-top: 12px;
  border-top: 1px dashed var(--line);
  font-size: 13px;
  line-height: 1.7;
  color: var(--ink-soft);
}

.sidebar-note a {
  display: inline-block;
  margin-right: 10px;
  color: var(--brand);
}

/* ============================================================
   components — 通用区块
   ============================================================ */

.section-title {
  font-size: 20px;
  font-weight: 700;
  line-height: 1.4;
  color: var(--ink);
  display: flex;
  align-items: baseline;
  gap: 10px;
}

.section-title::before {
  content: "";
  align-self: center;
  width: 4px;
  height: 18px;
  border-radius: 2px;
  background: var(--brand);
  flex: none;
}

.section-index,
.section-num {
  color: var(--brand);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.04em;
}

.section-lead,
.section-intro {
  margin-top: 10px;
  max-width: 46em;
  color: var(--ink-soft);
  font-size: 15px;
  line-height: 1.8;
}

.section-more {
  margin-top: 20px;
  font-size: 14px;
}

.section-more a {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  min-height: 40px;
  padding: 0 14px;
  border: 1px solid var(--brand);
  border-radius: var(--radius-sm);
  color: var(--brand);
  font-weight: 600;
}

.section-more a::after {
  content: "→";
  font-size: 14px;
}

.section-more a:hover,
.section-more a:focus-visible {
  background: var(--brand);
  color: #fff;
  text-decoration: none;
}

.sub-title {
  font-size: 15px;
  font-weight: 700;
  color: var(--ink);
  margin: 20px 0 10px;
}

/* 图片容器 */
figure {
  margin: 0;
}

figure img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  border-radius: var(--radius);
  background: #e9e7e0;
}

figcaption {
  margin-top: 8px;
  font-size: 13px;
  line-height: 1.6;
  color: var(--ink-soft);
}

/* 标签列表 */
.tag-list {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.tag-list li {
  padding: 4px 10px;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: var(--card-bg-soft);
  font-size: 13px;
  color: var(--ink-soft);
}

/* ============================================================
   pages — 首页
   ============================================================ */

.hero {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 420px);
  gap: 44px;
  align-items: center;
  padding: 48px 0 56px;
  border-bottom: 1px solid var(--line);
}

.hero-text {
  min-width: 0;
}

.hero-title {
  font-size: 34px;
  line-height: 1.32;
  font-weight: 700;
  color: var(--ink);
}

.hero-lead {
  margin-top: 16px;
  max-width: 44em;
  color: var(--ink-soft);
  font-size: 16px;
  line-height: 1.85;
}

.hero-paths {
  margin-top: 24px;
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.hero-paths a {
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  padding: 0 18px;
  border-radius: var(--radius-sm);
  border: 1px solid var(--brand);
  background: var(--brand);
  color: #fff;
  font-size: 15px;
  font-weight: 600;
}

.hero-paths li:nth-child(2) a,
.hero-paths li:nth-child(3) a {
  background: transparent;
  color: var(--brand);
}

.hero-paths a:hover,
.hero-paths a:focus-visible {
  background: var(--brand-deep);
  border-color: var(--brand-deep);
  color: #fff;
  text-decoration: none;
}

.hero-media {
  min-width: 0;
}

.hero-media img {
  width: 100%;
  aspect-ratio: 4 / 3;
  border-radius: var(--radius);
}

.hero-media figcaption {
  font-size: 13px;
}

/* 题材方向总览 */
.topic-overview {
  padding: 56px 0;
  border-bottom: 1px solid var(--line);
}

.topic-grid {
  margin-top: 26px;
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 18px;
}

.topic-card {
  display: flex;
  flex-direction: column;
  gap: 10px;
  padding: 18px 16px;
  background: var(--card-bg);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
}

.topic-index {
  font-size: 13px;
  font-weight: 700;
  color: var(--rank);
  letter-spacing: 0.06em;
}

.topic-name {
  font-size: 17px;
  font-weight: 700;
  color: var(--ink);
}

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

.topic-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
}

.topic-tags li {
  font-size: 12px;
  padding: 3px 8px;
  border-radius: 999px;
  background: #eef3f5;
  color: var(--brand-deep);
}

.topic-link {
  margin-top: auto;
  font-size: 14px;
  font-weight: 600;
  min-height: 36px;
  display: inline-flex;
  align-items: center;
}

.topic-link::after {
  content: "→";
  margin-left: 5px;
}

/* 封面墙 */
.cover-wall {
  padding: 56px 0;
  border-bottom: 1px solid var(--line);
}

.cover-grid {
  margin-top: 26px;
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 20px;
}

.cover-card {
  display: flex;
  flex-direction: column;
  background: var(--card-bg);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
  box-shadow: var(--shadow);
  transition: border-color 0.18s ease, transform 0.18s ease;
}

.cover-card:hover {
  border-color: var(--brand);
  transform: translateY(-2px);
}

.cover-card img {
  width: 100%;
  aspect-ratio: 3 / 4;
  border-radius: 0;
}

.cover-card:nth-child(4n + 1) img {
  aspect-ratio: 4 / 5;
}

.cover-card:nth-child(4n + 3) img {
  aspect-ratio: 1 / 1;
}

.cover-name {
  font-size: 16px;
  font-weight: 700;
  color: var(--ink);
  padding: 12px 14px 0;
}

.cover-meta {
  padding: 6px 14px 14px;
  font-size: 13px;
  color: var(--ink-soft);
}

/* 最近更新记录 */
.recent-block {
  padding: 56px 0;
  border-bottom: 1px solid var(--line);
}

.update-list {
  margin-top: 24px;
  display: flex;
  flex-direction: column;
  gap: 22px;
}

.update-group {
  background: var(--card-bg);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 16px 18px;
  box-shadow: var(--shadow);
}

.update-date {
  font-size: 14px;
  font-weight: 700;
  color: var(--rank);
  padding-bottom: 10px;
  margin-bottom: 8px;
  border-bottom: 1px dashed var(--line);
  letter-spacing: 0.02em;
}

.update-rows {
  display: flex;
  flex-direction: column;
}

.update-row {
  display: grid;
  grid-template-columns: minmax(0, 1.4fr) 130px 120px;
  gap: 12px;
  align-items: center;
  padding: 9px 0;
  border-bottom: 1px solid #f0eee8;
  font-size: 14px;
}

.update-row:last-child {
  border-bottom: none;
}

.update-name {
  font-weight: 600;
  color: var(--ink);
  min-width: 0;
}

.update-topic {
  color: var(--brand);
  font-size: 13px;
}

.update-range {
  color: var(--ink-soft);
  font-size: 13px;
  text-align: right;
}

/* 人气榜单（首页） */
.rank-block {
  padding: 56px 0;
  border-bottom: 1px solid var(--line);
}

.rank-list {
  margin-top: 24px;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.rank-row {
  display: grid;
  grid-template-columns: 40px minmax(0, 1fr) 120px minmax(0, 1.5fr);
  gap: 14px;
  align-items: baseline;
  padding: 12px 16px;
  background: var(--card-bg);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  font-size: 14px;
  box-shadow: var(--shadow);
}

.rank-row:hover {
  border-color: var(--brand);
}

.rank-no {
  font-size: 16px;
  font-weight: 700;
  color: var(--rank);
}

.rank-name {
  font-weight: 700;
  color: var(--ink);
  min-width: 0;
}

.rank-topic {
  font-size: 13px;
  color: var(--brand);
}

.rank-reason {
  font-size: 13px;
  line-height: 1.7;
  color: var(--ink-soft);
  min-width: 0;
}

/* 条目字段与收录边界摘要 */
.fields-summary {
  padding: 56px 0;
  border-bottom: 1px solid var(--line);
}

.fields-columns {
  margin-top: 24px;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 22px;
}

.fields-col {
  padding: 20px;
  background: var(--card-bg);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
}

.fields-col-title {
  font-size: 16px;
  font-weight: 700;
  color: var(--ink);
  margin-bottom: 10px;
}

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

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

.fields-points li {
  position: relative;
  padding-left: 16px;
  font-size: 14px;
  line-height: 1.75;
  color: var(--ink-soft);
}

.fields-points li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 10px;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--brand);
}

/* 站内栏目索引 */
.site-index {
  padding: 56px 0 0;
}

.index-grid {
  margin-top: 24px;
  display: grid;
  grid-template-columns: repeat(5, minmax(0, 1fr));
  gap: 14px;
}

.index-cell {
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 64px;
  padding: 12px;
  text-align: center;
  background: var(--card-bg);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  color: var(--ink);
  font-size: 15px;
  font-weight: 600;
  box-shadow: var(--shadow);
}

.index-cell:hover,
.index-cell:focus-visible {
  border-color: var(--brand);
  color: var(--brand);
  text-decoration: none;
}

/* ============================================================
   pages — 题材分类
   ============================================================ */

.direction-block {
  padding-bottom: 34px;
  margin-bottom: 34px;
  border-bottom: 1px solid var(--line);
}

.direction-block:last-of-type {
  border-bottom: none;
}

.direction-head {
  display: flex;
  align-items: baseline;
  gap: 10px;
}

.direction-index {
  font-size: 13px;
  font-weight: 700;
  color: var(--rank);
  letter-spacing: 0.06em;
}

.direction-media {
  margin-top: 18px;
}

.direction-media img {
  width: 100%;
  aspect-ratio: 16 / 7;
}

.direction-desc {
  margin-top: 16px;
  max-width: 46em;
  font-size: 15px;
  line-height: 1.85;
  color: var(--ink-soft);
}

.entry-list {
  display: flex;
  flex-direction: column;
  border-top: 1px solid var(--line);
}

.entry-row {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 150px 96px;
  gap: 12px;
  align-items: center;
  padding: 11px 0;
  border-bottom: 1px solid var(--line);
  font-size: 14px;
}

.entry-name {
  font-weight: 600;
  color: var(--ink);
  min-width: 0;
}

.entry-meta {
  font-size: 13px;
  color: var(--ink-soft);
}

.entry-link {
  font-size: 13px;
  font-weight: 600;
  text-align: right;
  min-height: 32px;
  display: inline-flex;
  align-items: center;
  justify-content: flex-end;
}

.path-block {
  padding-top: 30px;
  border-top: 1px solid var(--line);
}

.path-desc {
  margin-top: 10px;
  max-width: 46em;
  font-size: 15px;
  line-height: 1.8;
  color: var(--ink-soft);
}

.path-list {
  margin-top: 16px;
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.path-list a {
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  padding: 0 16px;
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
  background: var(--card-bg);
  color: var(--brand);
  font-size: 14px;
  font-weight: 600;
}

.path-list a:hover,
.path-list a:focus-visible {
  border-color: var(--brand);
  background: #eef3f5;
  text-decoration: none;
}

/* ============================================================
   pages — 最近更新
   ============================================================ */

.update-figure {
  margin-bottom: 32px;
}

.update-figure img {
  width: 100%;
  aspect-ratio: 16 / 6;
}

.content-section {
  padding-bottom: 34px;
  margin-bottom: 34px;
  border-bottom: 1px solid var(--line);
}

.content-section:last-of-type {
  border-bottom: none;
  margin-bottom: 0;
}

.date-group {
  margin-top: 24px;
  background: var(--card-bg);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 16px 18px;
  box-shadow: var(--shadow);
}

.date-heading {
  font-size: 14px;
  font-weight: 700;
  color: var(--rank);
  padding-bottom: 10px;
  margin-bottom: 6px;
  border-bottom: 1px dashed var(--line);
}

.date-group .update-list {
  margin-top: 0;
  gap: 0;
}

.date-group .update-row {
  grid-template-columns: minmax(0, 1.5fr) 130px 130px;
}

.rule-list {
  margin-top: 20px;
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 18px;
}

.rule-item {
  padding: 18px 16px;
  background: var(--card-bg);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
}

.rule-name {
  font-size: 15px;
  font-weight: 700;
  color: var(--ink);
  margin-bottom: 8px;
}

.rule-desc {
  font-size: 14px;
  line-height: 1.8;
  color: var(--ink-soft);
}

.cross-links {
  margin-top: 18px;
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.cross-link {
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  padding: 0 16px;
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
  background: var(--card-bg);
  color: var(--brand);
  font-size: 14px;
  font-weight: 600;
}

.cross-link:hover,
.cross-link:focus-visible {
  border-color: var(--brand);
  background: #eef3f5;
  text-decoration: none;
}

/* ============================================================
   pages — 人气榜单
   ============================================================ */

.section {
  padding-bottom: 34px;
  margin-bottom: 34px;
  border-bottom: 1px solid var(--line);
}

.section:last-of-type {
  border-bottom: none;
  margin-bottom: 0;
}

.rank-section .rank-list {
  margin-top: 24px;
  gap: 12px;
}

.rank-item {
  display: grid;
  grid-template-columns: 44px minmax(0, 1fr);
  gap: 16px;
  align-items: start;
  padding: 16px 18px;
  background: var(--card-bg);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  transition: border-color 0.18s ease;
}

.rank-item:hover {
  border-color: var(--brand);
}

.rank-item .rank-no {
  font-size: 20px;
  font-weight: 700;
  color: var(--rank);
  line-height: 1.4;
  text-align: center;
}

.rank-item .rank-cover {
  display: none;
}

.rank-item:nth-child(-n + 2) {
  grid-template-columns: 44px 92px minmax(0, 1fr);
}

.rank-item:nth-child(-n + 2) .rank-cover {
  display: block;
}

.rank-cover img {
  width: 92px;
  aspect-ratio: 3 / 4;
}

.rank-body {
  min-width: 0;
}

.rank-name {
  display: block;
  font-size: 16px;
  font-weight: 700;
  color: var(--ink);
}

.rank-meta,
.rank-body .rank-topic {
  display: inline-block;
  margin: 4px 10px 0 0;
  font-size: 13px;
  color: var(--brand);
}

.rank-body .rank-reason {
  display: block;
  margin-top: 6px;
  font-size: 14px;
  line-height: 1.8;
  color: var(--ink-soft);
}

.method-section .section-figure {
  margin-top: 20px;
}

.method-section .section-figure img {
  width: 100%;
  aspect-ratio: 16 / 6;
}

.method-section > p {
  margin-top: 16px;
  max-width: 46em;
  font-size: 15px;
  line-height: 1.85;
  color: var(--ink-soft);
}

.method-points {
  margin-top: 14px;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.method-points li {
  position: relative;
  padding-left: 16px;
  font-size: 14px;
  line-height: 1.8;
  color: var(--ink-soft);
}

.method-points li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 11px;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--rank);
}

.cross-section > p {
  margin-top: 10px;
  max-width: 46em;
  font-size: 15px;
  line-height: 1.8;
  color: var(--ink-soft);
}

.cross-section .cross-links {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 16px;
}

.cross-section .cross-links a {
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  padding: 0 16px;
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
  background: var(--card-bg);
  color: var(--brand);
  font-size: 14px;
  font-weight: 600;
}

.cross-section .cross-links a:hover,
.cross-section .cross-links a:focus-visible {
  border-color: var(--brand);
  background: #eef3f5;
  text-decoration: none;
}

/* ============================================================
   pages — 条目字段说明
   ============================================================ */

.page-section {
  padding-bottom: 34px;
  margin-bottom: 34px;
  border-bottom: 1px solid var(--line);
}

.page-section:last-of-type {
  border-bottom: none;
  margin-bottom: 0;
}

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

.section-media img {
  width: 100%;
  aspect-ratio: 16 / 6;
}

.field-list {
  margin-top: 22px;
  display: flex;
  flex-direction: column;
  gap: 14px;
}

.field-item {
  padding: 18px;
  background: var(--card-bg);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
}

.field-name {
  font-size: 16px;
  font-weight: 700;
  color: var(--ink);
  margin-bottom: 8px;
}

.field-text {
  font-size: 15px;
  line-height: 1.85;
  color: var(--ink-soft);
  max-width: 46em;
}

.standard-list {
  margin-top: 22px;
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 18px;
}

.standard-item {
  padding: 18px 16px;
  background: var(--card-bg);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
}

.standard-name {
  font-size: 15px;
  font-weight: 700;
  color: var(--ink);
  margin-bottom: 8px;
}

.standard-text {
  font-size: 14px;
  line-height: 1.8;
  color: var(--ink-soft);
}

.boundary-columns {
  margin-top: 22px;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 22px;
}

.boundary-col {
  padding: 20px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--card-bg);
  box-shadow: var(--shadow);
}

.boundary-in {
  border-top: 3px solid var(--brand);
}

.boundary-out {
  border-top: 3px solid var(--rank);
}

.boundary-title {
  font-size: 16px;
  font-weight: 700;
  color: var(--ink);
  margin-bottom: 12px;
}

.boundary-list {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.boundary-list li {
  position: relative;
  padding-left: 16px;
  font-size: 14px;
  line-height: 1.8;
  color: var(--ink-soft);
}

.boundary-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 11px;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--brand);
}

.boundary-out .boundary-list li::before {
  background: var(--rank);
}

.reading-paths {
  margin-top: 22px;
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 16px;
}

.path-item {
  display: flex;
  flex-direction: column;
  gap: 8px;
  padding: 18px 16px;
  background: var(--card-bg);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
}

.path-name {
  font-size: 15px;
  font-weight: 700;
  color: var(--ink);
}

.path-text {
  font-size: 14px;
  line-height: 1.75;
  color: var(--ink-soft);
}

.path-link {
  margin-top: auto;
  min-height: 36px;
  display: inline-flex;
  align-items: center;
  font-size: 14px;
  font-weight: 600;
}

.path-link::after {
  content: "→";
  margin-left: 5px;
}

.reading-note {
  margin-top: 22px;
  padding: 16px 18px;
  background: var(--card-bg-soft);
  border: 1px dashed var(--line);
  border-radius: var(--radius);
  font-size: 14px;
  line-height: 1.8;
  color: var(--ink-soft);
}

/* ============================================================
   pages — 404
   ============================================================ */

.error-main {
  max-width: var(--container);
  margin: 0 auto;
  padding: 56px 24px 72px;
}

.error-panel {
  padding: 40px 32px;
  background: var(--card-bg);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
}

.error-code {
  font-size: 14px;
  font-weight: 700;
  color: var(--rank);
  letter-spacing: 0.08em;
}

.error-panel h1 {
  margin-top: 10px;
  font-size: 34px;
  line-height: 1.3;
  font-weight: 700;
  color: var(--ink);
}

.error-lead {
  margin-top: 14px;
  max-width: 44em;
  font-size: 16px;
  line-height: 1.85;
  color: var(--ink-soft);
}

.error-tip {
  margin-top: 10px;
  max-width: 44em;
  font-size: 14px;
  line-height: 1.8;
  color: var(--ink-soft);
}

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

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 44px;
  padding: 0 20px;
  border-radius: var(--radius-sm);
  border: 1px solid transparent;
  font-size: 15px;
  font-weight: 600;
}

.btn-primary {
  background: var(--brand);
  border-color: var(--brand);
  color: #fff;
}

.btn-primary:hover,
.btn-primary:focus-visible {
  background: var(--brand-deep);
  border-color: var(--brand-deep);
  color: #fff;
  text-decoration: none;
}

.btn-ghost {
  background: transparent;
  border-color: var(--line);
  color: var(--ink);
}

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

.error-links {
  margin-top: 40px;
}

.error-links h2 {
  font-size: 20px;
  font-weight: 700;
  color: var(--ink);
}

.error-link-list {
  margin-top: 16px;
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 14px;
}

.error-link-list a {
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 56px;
  padding: 12px;
  text-align: center;
  background: var(--card-bg);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  color: var(--ink);
  font-size: 15px;
  font-weight: 600;
  box-shadow: var(--shadow);
}

.error-link-list a:hover,
.error-link-list a:focus-visible {
  border-color: var(--brand);
  color: var(--brand);
  text-decoration: none;
}

/* ============================================================
   layout — 页脚
   ============================================================ */

.site-footer {
  margin-top: auto;
  background: #f0eee8;
  border-top: 1px solid var(--line);
}

.footer-inner {
  max-width: var(--container);
  margin: 0 auto;
  padding: 40px 24px 24px;
  display: grid;
  grid-template-columns: minmax(0, 1.4fr) repeat(3, minmax(0, 1fr));
  gap: 32px;
}

.footer-brand {
  min-width: 0;
}

.footer-name {
  font-size: 17px;
  font-weight: 700;
  color: var(--ink);
}

.footer-desc {
  margin-top: 10px;
  max-width: 32em;
  font-size: 14px;
  line-height: 1.8;
  color: var(--ink-soft);
}

.footer-group-title {
  font-size: 14px;
  font-weight: 700;
  color: var(--ink);
  margin-bottom: 12px;
}

.footer-group ul {
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.footer-group a {
  display: inline-flex;
  align-items: center;
  min-height: 36px;
  font-size: 14px;
  color: var(--ink-soft);
}

.footer-group a:hover,
.footer-group a:focus-visible {
  color: var(--brand);
}

.footer-copy {
  max-width: var(--container);
  margin: 0 auto;
  padding: 16px 24px 28px;
  border-top: 1px solid var(--line);
  font-size: 13px;
  line-height: 1.7;
  color: var(--ink-soft);
}

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

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

  .cover-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

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

  .rule-list,
  .standard-list,
  .reading-paths {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .error-link-list {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (max-width: 900px) {
  .hero {
    grid-template-columns: minmax(0, 1fr);
    gap: 28px;
    padding: 36px 0 40px;
  }

  .hero-media {
    order: 2;
  }

  .page-layout,
  .page-layout.sidebar-left {
    grid-template-columns: minmax(0, 1fr);
    gap: 24px;
  }

  .page-sidebar,
  .page-aside,
  .category-sidebar {
    padding: 14px 14px 12px;
  }

  .sidebar-list,
  .aside-list {
    flex-direction: row;
    flex-wrap: nowrap;
    overflow-x: auto;
    gap: 8px;
    padding-bottom: 4px;
    -webkit-overflow-scrolling: touch;
    scrollbar-width: thin;
  }

  .sidebar-list li,
  .aside-list li {
    flex: 0 0 auto;
  }

  .sidebar-list a,
  .aside-list a {
    white-space: nowrap;
    border: 1px solid var(--line);
    background: var(--card-bg-soft);
    min-height: 44px;
  }

  .sidebar-note {
    margin-top: 10px;
  }

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

@media (max-width: 768px) {
  .home-main,
  .inner-main,
  .error-main {
    padding-left: 16px;
    padding-right: 16px;
  }

  .fact-bar {
    padding-left: 16px;
    padding-right: 16px;
  }

  .header-inner {
    padding: 10px 16px;
    gap: 12px;
  }

  .nav-toggle {
    display: block;
  }

  .site-nav {
    position: absolute;
    left: 0;
    right: 0;
    top: 100%;
    margin-left: 0;
    padding: 8px 16px 14px;
    background: var(--page-bg);
    border-bottom: 1px solid var(--line);
    box-shadow: 0 8px 18px rgba(31, 35, 40, 0.08);
  }

  .nav-list {
    display: none;
    flex-direction: column;
    align-items: stretch;
    gap: 2px;
  }

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

  .nav-list a {
    min-height: 48px;
    padding: 0 14px;
    font-size: 16px;
  }

  .page-title,
  .hero-title,
  .error-panel h1 {
    font-size: 26px;
  }

  .page-header {
    padding: 12px 0 20px;
    margin-bottom: 24px;
  }

  .hero-lead,
  .page-description,
  .section-lead,
  .section-intro {
    font-size: 15px;
  }

  .topic-overview,
  .cover-wall,
  .recent-block,
  .rank-block,
  .fields-summary {
    padding: 40px 0;
  }

  .topic-grid,
  .cover-grid,
  .fields-columns,
  .boundary-columns,
  .rule-list,
  .standard-list,
  .reading-paths {
    grid-template-columns: minmax(0, 1fr);
  }

  .cover-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 14px;
  }

  .index-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .update-row,
  .date-group .update-row {
    grid-template-columns: minmax(0, 1fr) auto;
    gap: 4px 10px;
    align-items: baseline;
  }

  .update-name {
    grid-column: 1 / -1;
    font-size: 15px;
  }

  .update-topic {
    grid-column: 1 / 2;
  }

  .update-range {
    grid-column: 2 / 3;
  }

  .rank-row {
    grid-template-columns: 32px minmax(0, 1fr);
    gap: 4px 12px;
  }

  .rank-row .rank-name {
    grid-column: 2 / 3;
  }

  .rank-row .rank-topic {
    grid-column: 2 / 3;
  }

  .rank-row .rank-reason {
    grid-column: 2 / 3;
  }

  .rank-item:nth-child(-n + 2) {
    grid-template-columns: 36px 72px minmax(0, 1fr);
  }

  .rank-cover img {
    width: 72px;
  }

  .entry-row {
    grid-template-columns: minmax(0, 1fr) auto;
    gap: 4px 10px;
    align-items: baseline;
  }

  .entry-name {
    grid-column: 1 / -1;
    font-size: 15px;
  }

  .entry-meta {
    grid-column: 1 / 2;
  }

  .entry-link {
    grid-column: 2 / 3;
  }

  .direction-media img,
  .update-figure img,
  .method-section .section-figure img,
  .section-media img {
    aspect-ratio: 16 / 9;
  }

  .error-panel {
    padding: 28px 20px;
  }
}

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

  .index-grid,
  .error-link-list {
    grid-template-columns: minmax(0, 1fr);
  }

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

  .hero-paths a {
    justify-content: center;
  }

  .footer-inner {
    grid-template-columns: minmax(0, 1fr);
    padding: 32px 16px 20px;
  }

  .footer-copy {
    padding: 14px 16px 24px;
  }

  .rank-item:nth-child(-n + 2) {
    grid-template-columns: 32px minmax(0, 1fr);
  }

  .rank-item:nth-child(-n + 2) .rank-cover {
    display: none;
  }
}