:root {
  --color-primary: #1f3a5f;
  --color-primary-soft: #2f5182;
  --color-accent: #e07a2f;
  --color-accent-soft: #f4a261;
  --color-bg: #f7f8fa;
  --color-card: #ffffff;
  --color-text: #2c2f33;
  --color-muted: #6b7280;
  --color-line: #e2e5ea;
  --color-line-soft: #eef1f5;
  --shadow-card: 0 1px 2px rgba(31, 58, 95, 0.06);
  --shadow-hover: 0 6px 16px rgba(31, 58, 95, 0.12);
  --radius-sm: 4px;
  --radius-md: 6px;
  --radius-lg: 8px;
  --container: 1180px;
  --content-narrow: 760px;
  --font-sans: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Source Han Sans SC", "Noto Sans CJK SC", system-ui, -apple-system, "Segoe UI", Arial, sans-serif;
  --font-mono: "SFMono-Regular", Consolas, "Liberation Mono", Menlo, monospace;
}

/* ==========================================================================
   base — 全局重置与基础排版
   ========================================================================== */

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

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

body {
  margin: 0;
  padding: 0;
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.75;
  color: var(--color-text);
  background-color: var(--color-bg);
}

img {
  max-width: 100%;
  height: auto;
  display: block;
  border: 0;
}

a {
  color: var(--color-primary);
  text-decoration: none;
  transition: color 0.15s ease;
}

a:hover {
  color: var(--color-accent);
}

a:focus-visible,
button:focus-visible,
summary:focus-visible {
  outline: 2px solid var(--color-accent);
  outline-offset: 2px;
  border-radius: var(--radius-sm);
}

h1,
h2,
h3,
h4 {
  margin: 0 0 0.6em;
  color: var(--color-primary);
  font-weight: 700;
  line-height: 1.35;
}

h1 { font-size: 32px; }
h2 { font-size: 22px; }
h3 { font-size: 18px; }
h4 { font-size: 16px; }

p {
  margin: 0 0 1em;
}

ul,
ol {
  margin: 0 0 1em;
  padding-left: 1.25em;
}

li {
  margin-bottom: 0.35em;
}

table {
  width: 100%;
  border-collapse: collapse;
  font-size: 15px;
}

th,
td {
  text-align: left;
  padding: 10px 12px;
  border-bottom: 1px solid var(--color-line-soft);
  vertical-align: top;
}

th {
  color: var(--color-primary);
  font-weight: 600;
  background-color: #f2f4f7;
}

caption {
  text-align: left;
  color: var(--color-muted);
  font-size: 14px;
  padding-bottom: 8px;
}

button {
  font-family: inherit;
  cursor: pointer;
}

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

/* ==========================================================================
   layout — 全站骨架：页头 / 导航 / 主容器 / 页脚
   ========================================================================== */

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

.site-header {
  position: sticky;
  top: 0;
  z-index: 40;
  background-color: var(--color-card);
  border-bottom: 1px solid var(--color-line);
}

.header-inner {
  max-width: var(--container);
  margin: 0 auto;
  padding: 0 24px;
  min-height: 64px;
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 12px 20px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  flex: 0 0 auto;
  color: var(--color-primary);
  font-weight: 700;
}

.brand:hover {
  color: var(--color-primary);
}

.brand-mark {
  width: 28px;
  height: 28px;
  border-radius: var(--radius-md);
  background-color: var(--color-primary);
  position: relative;
  flex: 0 0 auto;
}

.brand-mark::after {
  content: "";
  position: absolute;
  inset: 7px;
  border-radius: 2px;
  background-color: var(--color-accent);
}

.brand-name {
  font-size: 19px;
  letter-spacing: 0;
}

.nav-toggle {
  display: none;
  width: 44px;
  height: 44px;
  padding: 0;
  border: 1px solid var(--color-line);
  border-radius: var(--radius-md);
  background-color: var(--color-card);
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 4px;
}

.nav-toggle-bar {
  display: block;
  width: 20px;
  height: 2px;
  background-color: var(--color-primary);
  border-radius: 1px;
}

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

.nav-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  align-items: center;
  gap: 4px;
}

.nav-list li {
  margin: 0;
}

.nav-list a {
  display: inline-block;
  padding: 8px 14px;
  min-height: 44px;
  line-height: 28px;
  border-radius: var(--radius-md);
  color: var(--color-primary);
  font-size: 15px;
  font-weight: 500;
}

.nav-list a:hover {
  background-color: #f2f4f7;
  color: var(--color-accent);
}

.nav-list a.is-current {
  background-color: var(--color-primary);
  color: #ffffff;
}

.nav-list a.is-current:hover {
  background-color: var(--color-primary-soft);
  color: #ffffff;
}

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

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

.breadcrumb {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 6px;
  font-size: 14px;
  color: var(--color-muted);
  margin-bottom: 16px;
}

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

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

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

.page-header {
  margin-bottom: 28px;
  padding-bottom: 20px;
  border-bottom: 1px solid var(--color-line);
}

.page-title {
  font-size: 32px;
  font-weight: 700;
  color: var(--color-primary);
  margin: 0 0 10px;
}

.page-description {
  max-width: var(--content-narrow);
  margin: 0;
  font-size: 16px;
  color: var(--color-muted);
}

.site-footer {
  background-color: var(--color-primary);
  color: #d7dee8;
  font-size: 14px;
}

.footer-inner {
  max-width: var(--container);
  margin: 0 auto;
  padding: 40px 24px 24px;
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr 1fr;
  gap: 32px 28px;
}

.footer-brand-name {
  margin: 0 0 6px;
  font-size: 18px;
  font-weight: 700;
  color: #ffffff;
}

.footer-slogan {
  margin: 0 0 10px;
  color: var(--color-accent-soft);
  font-size: 14px;
}

.footer-desc {
  margin: 0;
  color: #b7c2d1;
  line-height: 1.7;
}

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

.footer-group-title {
  margin: 0 0 12px;
  font-size: 15px;
  font-weight: 600;
  color: #ffffff;
}

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

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

.footer-links a {
  color: #c8d2df;
  display: inline-block;
  padding: 2px 0;
}

.footer-links a:hover {
  color: var(--color-accent-soft);
}

.footer-copy {
  margin: 0;
  padding: 16px 24px 24px;
  border-top: 1px solid rgba(255, 255, 255, 0.12);
  text-align: center;
  color: #9fadbf;
  font-size: 13px;
}

.footer-year {
  font-family: var(--font-mono);
}

/* ==========================================================================
   components — 通用组件：区块标题 / 卡片 / 列表 / 表格 / 按钮 / FAQ
   ========================================================================== */

.section {
  margin-bottom: 44px;
}

.section-head {
  margin-bottom: 20px;
}

.section-title {
  font-size: 22px;
  font-weight: 700;
  color: var(--color-primary);
  margin: 0 0 8px;
}

.section-desc,
.section-intro,
.section-lead {
  max-width: var(--content-narrow);
  margin: 0 0 20px;
  color: var(--color-muted);
  font-size: 15px;
}

.column-title {
  font-size: 18px;
  font-weight: 700;
  color: var(--color-primary);
  margin: 0 0 6px;
}

.column-desc {
  margin: 0 0 16px;
  color: var(--color-muted);
  font-size: 14px;
}

.column-more {
  margin: 16px 0 0;
}

.column-more a {
  font-weight: 600;
  color: var(--color-accent);
}

.column-more a:hover {
  color: var(--color-primary);
}

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

.cover-card:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-hover);
}

.cover-card img {
  width: 100%;
  aspect-ratio: 3 / 4;
  object-fit: cover;
  background-color: #e9edf2;
}

.cover-card .cover-title {
  margin: 10px 12px 4px;
  font-size: 15px;
  font-weight: 600;
  color: var(--color-primary);
}

.cover-card .cover-meta {
  margin: 0 12px 12px;
  font-size: 13px;
  color: var(--color-muted);
}

.field-table {
  background-color: var(--color-card);
  border: 1px solid var(--color-line);
  border-radius: var(--radius-lg);
  overflow: hidden;
}

.field-table th,
.field-table td {
  border-bottom: 1px solid var(--color-line-soft);
}

.field-table tbody tr:last-child th,
.field-table tbody tr:last-child td {
  border-bottom: 0;
}

.btn {
  display: inline-block;
  padding: 10px 20px;
  min-height: 44px;
  line-height: 24px;
  border-radius: var(--radius-md);
  font-size: 15px;
  font-weight: 600;
  border: 1px solid transparent;
}

.btn-primary {
  background-color: var(--color-accent);
  color: #ffffff;
}

.btn-primary:hover {
  background-color: #c96a22;
  color: #ffffff;
}

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

.fact-bar {
  margin: 0;
  padding: 8px 24px;
  background-color: #eef1f5;
  color: var(--color-muted);
  font-size: 13px;
  text-align: center;
  border-bottom: 1px solid var(--color-line);
}

.home-main {
  max-width: var(--container);
  margin: 0 auto;
  padding: 28px 24px 56px;
}

.hero {
  margin-bottom: 44px;
}

.hero-inner {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
  gap: 32px;
  align-items: start;
  margin-bottom: 28px;
}

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

.hero-title {
  font-size: 32px;
  font-weight: 700;
  color: var(--color-primary);
  margin: 0 0 14px;
}

.hero-lead {
  max-width: 520px;
  margin: 0 0 20px;
  color: var(--color-text);
  font-size: 16px;
}

.hero-entries {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.hero-entries li {
  margin: 0;
}

.hero-entries a {
  display: inline-block;
  padding: 9px 16px;
  min-height: 44px;
  line-height: 26px;
  border: 1px solid var(--color-primary);
  border-radius: var(--radius-md);
  color: var(--color-primary);
  font-size: 15px;
  font-weight: 600;
  background-color: var(--color-card);
}

.hero-entries a:hover {
  background-color: var(--color-primary);
  color: #ffffff;
}

.hero-visual {
  margin: 0;
  background-color: var(--color-card);
  border: 1px solid var(--color-line);
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-card);
}

.hero-visual img {
  width: 100%;
  aspect-ratio: 16 / 10;
  object-fit: cover;
  background-color: #e9edf2;
}

.hero-visual figcaption {
  padding: 10px 14px;
  font-size: 13px;
  color: var(--color-muted);
  border-top: 1px solid var(--color-line-soft);
}

.hero-wall {
  display: grid;
  grid-template-columns: repeat(6, minmax(0, 1fr));
  gap: 14px;
}

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

.topic-col {
  background-color: var(--color-card);
  border: 1px solid var(--color-line);
  border-radius: var(--radius-lg);
  padding: 18px 16px;
  box-shadow: var(--shadow-card);
  min-width: 0;
}

.topic-name {
  margin: 0 0 8px;
  font-size: 17px;
  color: var(--color-primary);
}

.topic-trait {
  margin: 0 0 12px;
  font-size: 14px;
  color: var(--color-muted);
  min-height: 44px;
}

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

.topic-items li {
  margin-bottom: 8px;
}

.topic-items a {
  font-size: 14px;
  color: var(--color-primary);
}

.topic-items a:hover {
  color: var(--color-accent);
}

.cover-update-layout {
  display: grid;
  grid-template-columns: minmax(0, 1.6fr) minmax(0, 1fr);
  gap: 28px;
  align-items: start;
}

.cover-column {
  min-width: 0;
}

.cover-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 16px;
}

.update-column {
  min-width: 0;
  background-color: var(--color-card);
  border: 1px solid var(--color-line);
  border-radius: var(--radius-lg);
  padding: 18px 16px;
  box-shadow: var(--shadow-card);
}

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

.update-group {
  margin-bottom: 16px;
  padding-bottom: 12px;
  border-bottom: 1px dashed var(--color-line);
}

.update-group:last-child {
  margin-bottom: 0;
  padding-bottom: 0;
  border-bottom: 0;
}

.update-date {
  margin: 0 0 8px;
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--color-accent);
  font-weight: 600;
}

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

.update-rows li {
  margin-bottom: 8px;
  font-size: 14px;
  line-height: 1.6;
}

.update-rows a {
  color: var(--color-primary);
}

.update-rows a:hover {
  color: var(--color-accent);
}

.update-tag {
  display: inline-block;
  margin-left: 6px;
  padding: 1px 8px;
  border-radius: var(--radius-sm);
  background-color: #eef1f5;
  color: var(--color-muted);
  font-size: 12px;
}

.update-note {
  display: block;
  color: var(--color-muted);
  font-size: 13px;
}

.ranking-topics-layout {
  display: grid;
  grid-template-columns: minmax(0, 1.6fr) minmax(0, 1fr);
  gap: 28px;
  align-items: start;
}

.ranking-column {
  min-width: 0;
}

.rank-list {
  list-style: none;
  margin: 0;
  padding: 0;
  counter-reset: rank;
}

.rank-item {
  display: grid;
  grid-template-columns: 44px minmax(0, 1fr) minmax(160px, 240px);
  gap: 12px;
  align-items: center;
  padding: 12px 14px;
  background-color: var(--color-card);
  border: 1px solid var(--color-line);
  border-radius: var(--radius-lg);
  margin-bottom: 10px;
  box-shadow: var(--shadow-card);
  transition: transform 0.18s ease, box-shadow 0.18s ease;
}

.rank-item:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-hover);
}

.rank-item .rank-no {
  font-family: var(--font-mono);
  font-size: 18px;
  font-weight: 700;
  color: var(--color-accent);
  text-align: center;
}

.rank-item a {
  font-size: 15px;
  font-weight: 600;
  color: var(--color-primary);
}

.rank-item a:hover {
  color: var(--color-accent);
}

.rank-item .rank-reason {
  font-size: 13px;
  color: var(--color-muted);
}

.topics-column {
  min-width: 0;
}

.topic-cards {
  display: grid;
  gap: 14px;
}

.topic-card {
  background-color: var(--color-card);
  border: 1px solid var(--color-line);
  border-radius: var(--radius-lg);
  padding: 16px;
  box-shadow: var(--shadow-card);
  min-width: 0;
}

.topic-card-title {
  margin: 0 0 6px;
  font-size: 16px;
  color: var(--color-primary);
}

.topic-card-meta {
  margin: 0 0 8px;
  font-size: 13px;
  color: var(--color-accent);
}

.topic-card-desc {
  margin: 0;
  font-size: 14px;
  color: var(--color-muted);
}

.field-summary-layout {
  display: grid;
  grid-template-columns: minmax(0, 1.4fr) minmax(0, 1fr);
  gap: 28px;
  align-items: start;
}

.field-column {
  min-width: 0;
}

.boundary-column {
  min-width: 0;
  background-color: var(--color-card);
  border: 1px solid var(--color-line);
  border-radius: var(--radius-lg);
  padding: 18px 16px;
  box-shadow: var(--shadow-card);
}

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

.boundary-list li {
  position: relative;
  padding-left: 16px;
  margin-bottom: 10px;
  font-size: 14px;
  color: var(--color-text);
}

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

.site-index .index-grid {
  display: grid;
  grid-template-columns: repeat(5, minmax(0, 1fr));
  gap: 16px;
}

.index-col {
  background-color: var(--color-card);
  border: 1px solid var(--color-line);
  border-radius: var(--radius-lg);
  padding: 16px;
  box-shadow: var(--shadow-card);
  min-width: 0;
}

.index-name {
  margin: 0 0 8px;
  font-size: 16px;
}

.index-name a {
  color: var(--color-primary);
}

.index-name a:hover {
  color: var(--color-accent);
}

.index-desc {
  margin: 0;
  font-size: 13px;
  color: var(--color-muted);
}

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

.topics-section .topic-groups {
  display: grid;
  gap: 26px;
}

.topic-group {
  background-color: var(--color-card);
  border: 1px solid var(--color-line);
  border-radius: var(--radius-lg);
  padding: 22px 20px;
  box-shadow: var(--shadow-card);
}

.topic-group-head {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 10px 16px;
  margin-bottom: 10px;
}

.topic-group-title {
  margin: 0;
  font-size: 19px;
  color: var(--color-primary);
}

.topic-group-meta {
  margin: 0;
  font-size: 13px;
  color: var(--color-accent);
}

.topic-group-desc {
  max-width: var(--content-narrow);
  margin: 0 0 14px;
  color: var(--color-text);
  font-size: 15px;
}

.topic-points {
  margin: 0 0 18px;
  padding-left: 1.25em;
  color: var(--color-muted);
  font-size: 14px;
}

.topic-points li {
  margin-bottom: 6px;
}

.topic-entries {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 16px;
}

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

.entry-card:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-hover);
}

.entry-card img {
  width: 100%;
  aspect-ratio: 3 / 4;
  object-fit: cover;
  background-color: #e9edf2;
}

.entry-name {
  padding: 10px 12px 2px;
  font-size: 15px;
  font-weight: 600;
  color: var(--color-primary);
}

.entry-tag {
  padding: 0 12px 12px;
  font-size: 13px;
  color: var(--color-muted);
}

.topics-table-wrap {
  overflow-x: auto;
  border: 1px solid var(--color-line);
  border-radius: var(--radius-lg);
  background-color: var(--color-card);
}

.topics-table {
  min-width: 560px;
}

.topics-table-caption {
  padding: 14px 14px 0;
}

.topics-table tbody th {
  background-color: #fbfcfd;
}

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

.scope-col {
  background-color: var(--color-card);
  border: 1px solid var(--color-line);
  border-radius: var(--radius-lg);
  padding: 18px 16px;
  box-shadow: var(--shadow-card);
  min-width: 0;
}

.scope-col-title {
  margin: 0 0 10px;
  font-size: 16px;
  color: var(--color-primary);
}

.scope-list {
  margin: 0;
  padding-left: 1.25em;
  color: var(--color-muted);
  font-size: 14px;
}

.scope-list li {
  margin-bottom: 8px;
}

.related-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 16px;
}

.related-item {
  margin: 0;
}

.related-link {
  display: block;
  height: 100%;
  padding: 16px;
  background-color: var(--color-card);
  border: 1px solid var(--color-line);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-card);
  transition: transform 0.18s ease, box-shadow 0.18s ease;
}

.related-link:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-hover);
}

.related-name {
  display: block;
  font-size: 16px;
  font-weight: 600;
  color: var(--color-primary);
  margin-bottom: 6px;
}

.related-note {
  display: block;
  font-size: 13px;
  color: var(--color-muted);
}

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

.updates-timeline {
  margin-bottom: 44px;
}

.update-group {
  background-color: var(--color-card);
  border: 1px solid var(--color-line);
  border-radius: var(--radius-lg);
  padding: 18px 18px 8px;
  margin-bottom: 20px;
  box-shadow: var(--shadow-card);
}

.updates-timeline .update-date {
  font-family: var(--font-mono);
  font-size: 16px;
  color: var(--color-primary);
  margin: 0 0 12px;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--color-line-soft);
}

.updates-timeline .update-list {
  list-style: none;
  margin: 0;
  padding: 0;
}

.update-row {
  display: grid;
  grid-template-columns: 88px minmax(0, 1fr);
  gap: 16px;
  align-items: start;
  padding: 12px 0;
  border-bottom: 1px dashed var(--color-line);
}

.update-row:last-child {
  border-bottom: 0;
}

.update-thumb {
  margin: 0;
}

.update-thumb img {
  width: 88px;
  height: 118px;
  object-fit: cover;
  border-radius: var(--radius-md);
  background-color: #e9edf2;
}

.update-info {
  min-width: 0;
}

.update-title {
  margin: 0 0 4px;
  font-size: 16px;
  font-weight: 600;
  color: var(--color-primary);
}

.update-meta {
  margin: 0 0 4px;
  font-size: 13px;
  color: var(--color-muted);
}

.update-topic,
.update-progress {
  font-family: var(--font-mono);
}

.update-note {
  margin: 0;
  font-size: 14px;
  color: var(--color-text);
}

.updates-fields {
  margin-bottom: 44px;
}

.fields-footnote {
  margin: 14px 0 0;
  font-size: 14px;
  color: var(--color-muted);
}

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

.ranking-section {
  margin-bottom: 44px;
}

.ranking-layout {
  display: grid;
  grid-template-columns: minmax(0, 1.6fr) minmax(0, 1fr);
  gap: 28px;
  align-items: start;
}

.ranking-main {
  min-width: 0;
}

.ranking-visual {
  margin: 0 0 20px;
  background-color: var(--color-card);
  border: 1px solid var(--color-line);
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-card);
}

.ranking-visual img {
  width: 100%;
  aspect-ratio: 16 / 9;
  object-fit: cover;
  background-color: #e9edf2;
}

.ranking-visual figcaption {
  padding: 10px 14px;
  font-size: 13px;
  color: var(--color-muted);
  border-top: 1px solid var(--color-line-soft);
}

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

.ranking-item {
  display: grid;
  grid-template-columns: 48px 76px minmax(0, 1fr);
  gap: 14px;
  align-items: start;
  padding: 14px;
  background-color: var(--color-card);
  border: 1px solid var(--color-line);
  border-radius: var(--radius-lg);
  margin-bottom: 12px;
  box-shadow: var(--shadow-card);
  transition: transform 0.18s ease, box-shadow 0.18s ease;
}

.ranking-item:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-hover);
}

.ranking-item .rank-no {
  font-family: var(--font-mono);
  font-size: 20px;
  font-weight: 700;
  color: var(--color-accent);
  text-align: center;
  padding-top: 4px;
}

.rank-cover {
  margin: 0;
}

.rank-cover img {
  width: 76px;
  height: 100px;
  object-fit: cover;
  border-radius: var(--radius-md);
  background-color: #e9edf2;
}

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

.rank-name {
  margin: 0 0 4px;
  font-size: 16px;
  font-weight: 600;
  color: var(--color-primary);
}

.rank-meta {
  margin: 0 0 6px;
  font-size: 13px;
  color: var(--color-muted);
}

.rank-topic,
.rank-update {
  font-family: var(--font-mono);
}

.ranking-item .rank-reason {
  margin: 0;
  font-size: 14px;
  color: var(--color-text);
}

.ranking-aside {
  min-width: 0;
}

.topic-card-list {
  display: grid;
  gap: 16px;
}

.topic-card-list .topic-card {
  padding: 0;
  overflow: hidden;
}

.topic-cover {
  margin: 0;
}

.topic-cover img {
  width: 100%;
  aspect-ratio: 16 / 9;
  object-fit: cover;
  background-color: #e9edf2;
}

.topic-card-list .topic-name {
  margin: 12px 16px 4px;
  font-size: 16px;
  color: var(--color-primary);
}

.topic-card-list .topic-meta {
  margin: 0 16px 8px;
  font-size: 13px;
  color: var(--color-accent);
}

.topic-card-list .topic-desc {
  margin: 0 16px 12px;
  font-size: 14px;
  color: var(--color-muted);
}

.topic-link {
  display: inline-block;
  margin: 0 16px 16px;
  font-size: 14px;
  font-weight: 600;
  color: var(--color-accent);
}

.topic-link:hover {
  color: var(--color-primary);
}

.ranking-notes {
  margin-bottom: 44px;
}

.ranking-notes-text {
  max-width: var(--content-narrow);
  color: var(--color-text);
}

.ranking-table {
  background-color: var(--color-card);
  border: 1px solid var(--color-line);
  border-radius: var(--radius-lg);
  overflow: hidden;
  margin-top: 16px;
}

.column-index {
  margin-bottom: 20px;
}

.column-index-grid {
  display: grid;
  grid-template-columns: repeat(5, minmax(0, 1fr));
  gap: 16px;
}

.column-index-item {
  background-color: var(--color-card);
  border: 1px solid var(--color-line);
  border-radius: var(--radius-lg);
  padding: 16px;
  box-shadow: var(--shadow-card);
  min-width: 0;
}

.column-index-name {
  margin: 0 0 8px;
  font-size: 16px;
}

.column-index-name a {
  color: var(--color-primary);
}

.column-index-name a:hover {
  color: var(--color-accent);
}

.column-index-desc {
  margin: 0;
  font-size: 13px;
  color: var(--color-muted);
}

/* ==========================================================================
   pages — 阅读说明页
   ========================================================================== */

.guide-visual,
.guide-fields,
.guide-rules,
.guide-faq,
.guide-links {
  margin-bottom: 44px;
}

.guide-figure {
  margin: 0;
  background-color: var(--color-card);
  border: 1px solid var(--color-line);
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-card);
}

.guide-figure img {
  width: 100%;
  aspect-ratio: 16 / 9;
  object-fit: cover;
  background-color: #e9edf2;
}

.guide-figure figcaption {
  padding: 10px 14px;
  font-size: 13px;
  color: var(--color-muted);
  border-top: 1px solid var(--color-line-soft);
}

.rule-block {
  background-color: var(--color-card);
  border: 1px solid var(--color-line);
  border-radius: var(--radius-lg);
  padding: 18px 18px 8px;
  margin-bottom: 16px;
  box-shadow: var(--shadow-card);
}

.rule-title {
  margin: 0 0 8px;
  font-size: 16px;
  color: var(--color-primary);
}

.rule-block p {
  margin: 0 0 12px;
  color: var(--color-text);
  font-size: 15px;
}

.faq-item {
  background-color: var(--color-card);
  border: 1px solid var(--color-line);
  border-radius: var(--radius-lg);
  margin-bottom: 12px;
  box-shadow: var(--shadow-card);
  overflow: hidden;
}

.faq-question {
  padding: 14px 44px 14px 18px;
  min-height: 44px;
  font-size: 16px;
  font-weight: 600;
  color: var(--color-primary);
  cursor: pointer;
  list-style: none;
  position: relative;
}

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

.faq-question::after {
  content: "+";
  position: absolute;
  right: 18px;
  top: 50%;
  transform: translateY(-50%);
  font-size: 20px;
  font-weight: 400;
  color: var(--color-accent);
}

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

.faq-answer {
  padding: 0 18px 16px;
  border-top: 1px solid var(--color-line-soft);
}

.faq-answer p {
  margin: 12px 0 0;
  font-size: 15px;
  color: var(--color-text);
}

.guide-link-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 16px;
}

.guide-link-list li {
  margin: 0;
}

.guide-link-list a {
  display: block;
  padding: 14px 16px;
  min-height: 44px;
  background-color: var(--color-card);
  border: 1px solid var(--color-line);
  border-radius: var(--radius-lg);
  font-weight: 600;
  color: var(--color-primary);
  box-shadow: var(--shadow-card);
  transition: transform 0.18s ease, box-shadow 0.18s ease;
}

.guide-link-list a:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-hover);
  color: var(--color-accent);
}

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

.error-main {
  max-width: var(--container);
  margin: 0 auto;
  padding: 48px 24px 64px;
}

.error-hero {
  text-align: center;
  margin-bottom: 40px;
}

.error-code {
  margin: 0 0 8px;
  font-family: var(--font-mono);
  font-size: 56px;
  font-weight: 700;
  color: var(--color-accent);
  line-height: 1;
}

.error-title {
  font-size: 28px;
  color: var(--color-primary);
  margin: 0 0 12px;
}

.error-desc {
  max-width: 560px;
  margin: 0 auto 22px;
  color: var(--color-muted);
}

.error-routes {
  background-color: var(--color-card);
  border: 1px solid var(--color-line);
  border-radius: var(--radius-lg);
  padding: 22px 20px;
  box-shadow: var(--shadow-card);
}

.route-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 16px;
}

.route-item {
  margin: 0;
  padding: 14px 16px;
  border: 1px solid var(--color-line);
  border-radius: var(--radius-lg);
  background-color: #fbfcfd;
  min-width: 0;
}

.route-link {
  display: inline-block;
  font-size: 16px;
  font-weight: 600;
  color: var(--color-primary);
  margin-bottom: 6px;
}

.route-link:hover {
  color: var(--color-accent);
}

.route-desc {
  margin: 0;
  font-size: 13px;
  color: var(--color-muted);
}

/* ==========================================================================
   responsive — 1024px 与 768px 断点
   ========================================================================== */

@media (max-width: 1024px) {
  .hero-inner {
    grid-template-columns: minmax(0, 1fr);
    gap: 24px;
  }

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

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

  .cover-update-layout,
  .ranking-topics-layout,
  .ranking-layout,
  .field-summary-layout {
    grid-template-columns: minmax(0, 1fr);
  }

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

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

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

@media (max-width: 768px) {
  .header-inner {
    padding: 10px 16px;
    min-height: 56px;
    justify-content: space-between;
    flex-wrap: nowrap;
  }

  .nav-toggle {
    display: flex;
  }

  .site-nav {
    flex: 1 0 100%;
    order: 3;
  }

  .nav-list {
    display: none;
    flex-direction: column;
    align-items: stretch;
    width: 100%;
    gap: 2px;
    padding: 8px 0 4px;
    border-top: 1px solid var(--color-line);
  }

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

  .nav-list a {
    display: block;
    padding: 10px 12px;
    min-height: 44px;
    line-height: 24px;
    border-radius: var(--radius-md);
  }

  .fact-bar {
    padding: 8px 16px;
    font-size: 12px;
  }

  .home-main,
  .inner-main,
  .error-main {
    padding-left: 16px;
    padding-right: 16px;
  }

  .home-main {
    padding-top: 20px;
    padding-bottom: 40px;
  }

  .inner-main {
    padding-top: 18px;
    padding-bottom: 40px;
  }

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

  .error-title {
    font-size: 22px;
  }

  h2,
  .section-title {
    font-size: 19px;
  }

  h3,
  .column-title {
    font-size: 17px;
  }

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

  .topics-overview .topic-grid,
  .cover-grid,
  .topic-entries,
  .scope-columns,
  .site-index .index-grid,
  .column-index-grid,
  .related-list,
  .guide-link-list,
  .route-list {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .rank-item {
    grid-template-columns: 36px minmax(0, 1fr);
    row-gap: 4px;
  }

  .rank-item .rank-reason {
    grid-column: 2 / -1;
  }

  .ranking-item {
    grid-template-columns: 36px 64px minmax(0, 1fr);
    gap: 10px;
    padding: 12px;
  }

  .rank-cover img {
    width: 64px;
    height: 84px;
  }

  .update-row {
    grid-template-columns: 72px minmax(0, 1fr);
    gap: 12px;
  }

  .update-thumb img {
    width: 72px;
    height: 96px;
  }

  .footer-inner {
    grid-template-columns: minmax(0, 1fr);
    gap: 24px;
    padding: 32px 16px 20px;
  }

  .footer-copy {
    padding: 14px 16px 20px;
  }
}

@media (max-width: 480px) {
  .cover-grid,
  .topic-entries,
  .related-list,
  .guide-link-list,
  .route-list,
  .topics-overview .topic-grid,
  .site-index .index-grid,
  .column-index-grid {
    grid-template-columns: minmax(0, 1fr);
  }

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

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

  .hero-entries a {
    text-align: center;
  }
}

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

  *,
  *::before,
  *::after {
    transition-duration: 0.01ms !important;
    animation-duration: 0.01ms !important;
  }
}