/* ============================================================
   tuzlut.com · 里番动漫题材索引站 全站样式表
   视觉方向：数据新闻编辑风漫画索引站
   ============================================================ */

/* ============================================================
   1. Base / Reset / 设计变量
   ============================================================ */

:root {
  --color-ink: #1f2421;
  --color-paper: #f5f3ee;
  --color-paper-deep: #ece8df;
  --color-accent: #c34f3a;
  --color-accent-deep: #a83e2c;
  --color-teal: #305c66;
  --color-hairline: #e8e3d8;
  --color-white: #ffffff;
  --color-text-soft: #5a615c;

  --font-serif: "Songti SC", "Noto Serif CJK SC", "Source Han Serif SC", "SimSun", "STSong", serif;
  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;

  --container-width: 1200px;
  --content-max: 1180px;
  --read-max: 720px;

  --space-xs: 8px;
  --space-sm: 16px;
  --space-md: 24px;
  --space-lg: 40px;
  --space-xl: 64px;
  --space-xxl: 96px;

  --radius-sm: 4px;
  --radius-md: 8px;
  --radius-lg: 8px;

  --header-h: 64px;
  --font-size-body: 17px;
  --font-size-body-mobile: 16px;
  --line-height-body: 1.8;
}

*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

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

body {
  font-family: var(--font-sans);
  font-size: var(--font-size-body);
  line-height: var(--line-height-body);
  color: var(--color-ink);
  background-color: var(--color-paper);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

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

a {
  color: var(--color-teal);
  text-decoration: none;
  transition: color 0.2s ease;
}

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

ul,
ol {
  list-style: none;
}

h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-serif);
  line-height: 1.4;
  font-weight: 700;
  color: var(--color-ink);
}

h1 {
  font-size: 30px;
  line-height: 1.35;
}

h2 {
  font-size: 20px;
}

h3 {
  font-size: 17px;
}

p {
  margin-bottom: 12px;
}

figure {
  margin: 0;
}

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

table {
  width: 100%;
  border-collapse: collapse;
  font-size: 15px;
  line-height: 1.7;
}

th,
td {
  text-align: left;
  padding: 10px 14px;
  border-bottom: 1px solid var(--color-hairline);
  vertical-align: top;
}

th {
  font-family: var(--font-serif);
  font-weight: 700;
  background-color: var(--color-paper-deep);
  border-bottom: 2px solid var(--color-ink);
}

td {
  background-color: var(--color-white);
}

.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;
}

/* ============================================================
   2. Layout · 全站骨架
   ============================================================ */

.site-body {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

.site-main {
  flex: 1 0 auto;
  width: 100%;
}

.site-home {
  background-color: var(--color-paper);
}

.site-error {
  background-color: var(--color-paper);
}

.site-inner {
  background-color: var(--color-paper);
}

.inner-main {
  width: 100%;
  max-width: var(--content-max);
  margin: 0 auto;
  padding: 0 var(--space-md);
}

/* ============================================================
   3. Header / 全站页头
   ============================================================ */

.site-header {
  background-color: var(--color-white);
  border-bottom: 1px solid var(--color-hairline);
  position: sticky;
  top: 0;
  z-index: 100;
}

.header-inner {
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 0 var(--space-md);
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: var(--header-h);
  gap: var(--space-md);
}

.brand-link {
  font-family: var(--font-serif);
  font-size: 24px;
  font-weight: 700;
  color: var(--color-ink);
  letter-spacing: 0.04em;
  flex-shrink: 0;
  line-height: 1.2;
}

.brand-link:hover {
  color: var(--color-accent);
  text-decoration: none;
}

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

.site-nav .nav-list a {
  display: block;
  padding: 8px 14px;
  font-size: 15px;
  color: var(--color-ink);
  border-radius: var(--radius-sm);
  white-space: nowrap;
  line-height: 1.4;
}

.site-nav .nav-list a:hover {
  color: var(--color-accent);
  background-color: var(--color-paper);
  text-decoration: none;
}

.site-nav .nav-list a.is-current {
  color: var(--color-accent);
  font-weight: 700;
  background-color: var(--color-paper);
}

.nav-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 44px;
  height: 44px;
  padding: 10px 9px;
  background: transparent;
  border: 1px solid var(--color-hairline);
  border-radius: var(--radius-sm);
  cursor: pointer;
}

.nav-toggle span {
  display: block;
  height: 2px;
  width: 100%;
  background-color: var(--color-ink);
  border-radius: 2px;
  transition: transform 0.2s ease, opacity 0.2s ease;
}

.nav-toggle[aria-expanded="true"] span:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}

.nav-toggle[aria-expanded="true"] span:nth-child(2) {
  opacity: 0;
}

.nav-toggle[aria-expanded="true"] span:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

/* ============================================================
   4. Footer / 全站页脚
   ============================================================ */

.site-footer {
  background-color: var(--color-ink);
  color: #d8d5cc;
  margin-top: var(--space-xl);
}

.footer-inner {
  max-width: var(--container-width);
  margin: 0 auto;
  padding: var(--space-lg) var(--space-md) var(--space-sm);
}

.footer-brand {
  padding-bottom: var(--space-md);
  border-bottom: 1px solid rgba(255, 255, 255, 0.12);
  margin-bottom: var(--space-md);
}

.footer-sitename {
  font-family: var(--font-serif);
  font-size: 22px;
  font-weight: 700;
  color: var(--color-white);
  margin-bottom: 4px;
}

.footer-tagline {
  font-size: 14px;
  color: #a8a49b;
  margin-bottom: 0;
}

.footer-links {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: var(--space-md);
  padding-bottom: var(--space-md);
}

.footer-col h4 {
  font-family: var(--font-sans);
  font-size: 14px;
  font-weight: 700;
  color: var(--color-white);
  margin-bottom: 12px;
  letter-spacing: 0.02em;
}

.footer-col ul li {
  margin-bottom: 6px;
}

.footer-col ul a {
  color: #b5b1a8;
  font-size: 14px;
  line-height: 1.6;
}

.footer-col ul a:hover {
  color: var(--color-white);
  text-decoration: underline;
}

.footer-bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.12);
  padding: var(--space-sm) 0;
}

.footer-bottom p {
  font-size: 13px;
  color: #8f8b83;
  margin-bottom: 0;
  line-height: 1.6;
}

/* ============================================================
   5. Breadcrumb / 面包屑
   ============================================================ */

.breadcrumb {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 6px;
  font-size: 14px;
  padding: var(--space-sm) 0;
  margin-bottom: var(--space-sm);
  border-bottom: 1px solid var(--color-hairline);
}

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

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

.breadcrumb-sep {
  color: #b0aca3;
  font-size: 12px;
}

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

/* ============================================================
   6. Page Header / 统一页面标题区
   ============================================================ */

.page-header {
  padding: var(--space-md) 0 var(--space-lg);
  border-bottom: 1px solid var(--color-hairline);
  margin-bottom: var(--space-lg);
}

.page-title {
  font-size: 30px;
  font-weight: 700;
  margin-bottom: 10px;
  color: var(--color-ink);
}

.page-description {
  font-size: 16px;
  color: var(--color-text-soft);
  line-height: 1.8;
  margin-bottom: 0;
  max-width: var(--read-max);
}

/* ============================================================
   7. Sidebar Layout · 内页双栏骨架
   ============================================================ */

.layout-shell {
  width: 100%;
  max-width: var(--content-max);
  margin: 0 auto;
  padding: 0 var(--space-md);
}

/* ---- 左侧栏布局：侧栏先于 main 写入 DOM ---- */

.sidebar-left {
  display: grid;
  grid-template-columns: 280px 1fr;
  gap: var(--space-lg);
  align-items: start;
  padding-top: var(--space-sm);
}

.sidebar-left > .sidebar-nav,
.sidebar-left > .page-aside {
  grid-column: 1;
  position: sticky;
  top: calc(var(--header-h) + 16px);
}

.sidebar-left > .site-main,
.sidebar-left > .page-content {
  grid-column: 2;
  min-width: 0;
}

/* wenda.html 特殊：aside 在前、main 内容在 .page-content */
.sidebar-left .page-layout {
  display: grid;
  grid-template-columns: 280px 1fr;
  gap: var(--space-lg);
  align-items: start;
  width: 100%;
}

.sidebar-left .page-layout > .page-aside {
  grid-column: 1;
  position: sticky;
  top: calc(var(--header-h) + 16px);
}

.sidebar-left .page-layout > .page-content {
  grid-column: 2;
  min-width: 0;
}

/* ---- 右侧栏布局：main 在前、aside 在后 ---- */

.sidebar-right {
  display: grid;
  grid-template-columns: 1fr 320px;
  gap: var(--space-lg);
  align-items: start;
  padding-top: var(--space-sm);
}

.sidebar-right > .site-main {
  grid-column: 1;
  min-width: 0;
}

.sidebar-right > .guide-aside {
  grid-column: 2;
  position: sticky;
  top: calc(var(--header-h) + 16px);
}

/* ---- 通用双栏（guanzhu 等） ---- */

.page-layout.layout-shell {
  display: grid;
  grid-template-columns: 1fr 320px;
  gap: var(--space-lg);
  align-items: start;
  padding-top: var(--space-sm);
}

.page-layout.layout-shell > .site-main {
  grid-column: 1;
  min-width: 0;
}

.page-layout.layout-shell > .observe-aside {
  grid-column: 2;
  position: sticky;
  top: calc(var(--header-h) + 16px);
}

/* ---- zhuanti 双栏：main 在 .content-column，aside 在 .aside-column ---- */

.layout-shell:has(.content-column) {
  display: grid;
  grid-template-columns: 1fr 300px;
  gap: var(--space-lg);
  align-items: start;
}

.content-column {
  grid-column: 1;
  min-width: 0;
}

.topic-aside {
  grid-column: 2;
  min-width: 0;
}

/* ============================================================
   8. Sidebar Navigation · 分类树（fenlei）
   ============================================================ */

.sidebar-nav {
  background-color: var(--color-white);
  border: 1px solid var(--color-hairline);
  border-radius: var(--radius-md);
  padding: var(--space-sm) 0;
}

.category-tree .tree-title {
  font-size: 16px;
  padding: 0 var(--space-md) var(--space-sm);
  border-bottom: 1px solid var(--color-hairline);
  margin-bottom: var(--space-xs);
}

.tree-group {
  padding: 0;
}

.tree-group-title {
  font-size: 15px;
  font-weight: 700;
  padding: 8px var(--space-md);
  cursor: default;
  display: flex;
  align-items: center;
  justify-content: space-between;
  color: var(--color-ink);
}

.tree-group ul {
  padding: 0 0 8px;
}

.tree-group ul li a {
  display: block;
  padding: 6px var(--space-md) 6px calc(var(--space-md) + 12px);
  font-size: 14px;
  color: var(--color-text-soft);
  border-left: 2px solid transparent;
  line-height: 1.5;
}

.tree-group ul li a:hover {
  color: var(--color-accent);
  background-color: var(--color-paper);
  text-decoration: none;
}

.tree-group.is-open > .tree-group-title {
  color: var(--color-accent);
}

.tree-group.is-open ul li a {
  border-left-color: var(--color-hairline);
}

.tree-group.is-open ul li a:hover {
  border-left-color: var(--color-accent);
}

/* ============================================================
   9. Buttons / 按钮
   ============================================================ */

.btn-primary,
.btn-secondary,
.module-link,
.group-entry {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 12px 28px;
  font-size: 15px;
  font-weight: 700;
  border-radius: var(--radius-sm);
  line-height: 1.4;
  min-height: 44px;
  transition: background-color 0.2s ease, color 0.2s ease, border-color 0.2s ease;
}

.btn-primary {
  background-color: var(--color-accent);
  color: var(--color-white);
  border: 1px solid var(--color-accent);
}

.btn-primary:hover {
  background-color: var(--color-accent-deep);
  border-color: var(--color-accent-deep);
  color: var(--color-white);
  text-decoration: none;
}

.btn-secondary {
  background-color: transparent;
  color: var(--color-ink);
  border: 1px solid var(--color-ink);
}

.btn-secondary:hover {
  background-color: var(--color-ink);
  color: var(--color-paper);
  text-decoration: none;
}

/* ============================================================
   10. Homepage · 首页模块
   ============================================================ */

.home-main {
  padding-bottom: var(--space-lg);
}

/* ---- Hero 主区 ---- */

.hero-section {
  display: grid;
  grid-template-columns: 1.05fr 0.95fr;
  gap: var(--space-lg);
  align-items: center;
  padding: var(--space-xl) var(--space-md);
  max-width: var(--container-width);
  margin: 0 auto;
  border-bottom: 1px solid var(--color-hairline);
}

.hero-copy h1 {
  margin-bottom: var(--space-sm);
}

.hero-lead {
  font-size: 17px;
  color: var(--color-text-soft);
  margin-bottom: var(--space-md);
  max-width: 56ch;
}

.hero-actions {
  display: flex;
  gap: var(--space-sm);
  flex-wrap: wrap;
}

.hero-visual {
  position: relative;
}

.hero-figure {
  background-color: var(--color-paper-deep);
  border: 1px solid var(--color-hairline);
  border-radius: var(--radius-md);
  overflow: hidden;
}

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

.hero-note {
  font-size: 13px;
  color: var(--color-text-soft);
  margin-top: var(--space-xs);
  border-left: 2px solid var(--color-accent);
  padding-left: 10px;
  line-height: 1.6;
  margin-bottom: 0;
}

/* 首页首屏下方通栏示意图 */
.content-media-primary {
  max-width: var(--container-width);
  margin: 0 auto;
  padding: var(--space-sm) var(--space-md) 0;
}

.content-media-primary img {
  width: 100%;
  aspect-ratio: 21 / 8;
  object-fit: cover;
  border-radius: var(--radius-md);
  border: 1px solid var(--color-hairline);
}

.content-media-primary figcaption {
  text-align: center;
}

/* ---- 通用章节容器 ---- */

.section-block {
  max-width: var(--container-width);
  margin: 0 auto;
  padding: var(--space-xl) var(--space-md);
  border-bottom: 1px solid var(--color-hairline);
}

.section-block > h2 {
  font-size: 22px;
  margin-bottom: var(--space-sm);
  position: relative;
  padding-left: 0;
}

.section-block > h2::before {
  content: attr(data-index);
  display: inline-block;
  font-family: var(--font-serif);
  font-size: 14px;
  color: var(--color-accent);
  margin-right: 8px;
  vertical-align: middle;
}

.section-intro {
  font-size: 16px;
  color: var(--color-text-soft);
  max-width: 66ch;
  margin-bottom: var(--space-md);
}

/* ---- 信息如何组织 ---- */

.info-organization {
  background-color: var(--color-white);
}

.info-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-lg);
}

.info-item {
  border-top: 3px solid var(--color-ink);
  padding-top: var(--space-sm);
}

.info-item h3 {
  font-size: 18px;
  margin-bottom: 10px;
}

.info-item p {
  font-size: 15px;
  color: var(--color-text-soft);
  line-height: 1.8;
  margin-bottom: 8px;
}

/* ---- 题材标签入口区 ---- */

.taxonomy-entry {
  background-color: var(--color-paper);
}

.tag-group-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--space-md);
}

.tag-group {
  background-color: var(--color-white);
  border: 1px solid var(--color-hairline);
  border-radius: var(--radius-md);
  padding: var(--space-md);
  display: flex;
  flex-direction: column;
}

.tag-group h3 {
  font-size: 18px;
  margin-bottom: 6px;
  color: var(--color-ink);
}

.tag-group p {
  font-size: 14px;
  color: var(--color-text-soft);
  margin-bottom: var(--space-sm);
  line-height: 1.6;
}

.tag-chip-list {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: var(--space-sm);
}

.tag-chip-list li a {
  display: inline-block;
  padding: 6px 14px;
  background-color: var(--color-paper);
  border: 1px solid var(--color-hairline);
  border-radius: 999px;
  font-size: 14px;
  color: var(--color-ink);
  line-height: 1.4;
  transition: border-color 0.2s ease, color 0.2s ease;
}

.tag-chip-list li a:hover {
  border-color: var(--color-accent);
  color: var(--color-accent);
  text-decoration: none;
}

.group-entry {
  margin-top: auto;
  padding: 8px 16px;
  font-size: 14px;
  min-height: 40px;
  justify-content: flex-start;
  background-color: transparent;
  border: none;
  border-top: 1px solid var(--color-hairline);
  border-radius: 0;
  color: var(--color-teal);
  font-weight: 700;
  width: 100%;
}

.group-entry:hover {
  color: var(--color-accent);
  background-color: var(--color-paper);
  text-decoration: none;
}

/* ---- 专题与观察双栏 ---- */

.dual-modules {
  background-color: var(--color-white);
}

.dual-modules > h2 {
  margin-bottom: var(--space-md);
}

.dual-modules .dual-module {
  display: block;
}

.dual-modules {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-md);
}

.dual-modules > h2 {
  grid-column: 1 / -1;
}

.dual-module {
  background-color: var(--color-paper);
  border: 1px solid var(--color-hairline);
  border-radius: var(--radius-md);
  padding: var(--space-md);
  border-top: 3px solid var(--color-teal);
}

.dual-module:last-child {
  border-top-color: var(--color-accent);
}

.dual-module h2 {
  font-size: 19px;
  margin-bottom: 10px;
}

.dual-module p {
  font-size: 15px;
  color: var(--color-text-soft);
  line-height: 1.75;
  margin-bottom: 10px;
}

.module-link {
  margin-top: 8px;
  padding: 10px 20px;
  font-size: 14px;
  min-height: 42px;
  background-color: transparent;
  border: 1px solid var(--color-teal);
  color: var(--color-teal);
}

.module-link:hover {
  background-color: var(--color-teal);
  color: var(--color-white);
  text-decoration: none;
}

.dual-module:last-child .module-link {
  border-color: var(--color-accent);
  color: var(--color-accent);
}

.dual-module:last-child .module-link:hover {
  background-color: var(--color-accent);
  color: var(--color-white);
}

/* ---- 阅读支持三卡 ---- */

.support-cards {
  background-color: var(--color-paper);
}

.support-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--space-md);
}

.support-card {
  background-color: var(--color-white);
  border: 1px solid var(--color-hairline);
  border-radius: var(--radius-md);
  padding: var(--space-md);
  display: flex;
  flex-direction: column;
  transition: box-shadow 0.2s ease;
}

.support-card:hover {
  box-shadow: 0 4px 16px rgba(31, 36, 33, 0.06);
}

.support-card h3 {
  font-size: 17px;
  margin-bottom: 8px;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--color-hairline);
}

.support-card p {
  font-size: 14px;
  color: var(--color-text-soft);
  line-height: 1.7;
  margin-bottom: var(--space-sm);
  flex: 1;
}

.support-card a {
  font-size: 14px;
  font-weight: 700;
  color: var(--color-accent);
  display: inline-flex;
  align-items: center;
  gap: 4px;
  min-height: 44px;
}

.support-card a:hover {
  text-decoration: underline;
}

/* ---- 快速路径（首页收尾） ---- */

.quick-path {
  background-color: var(--color-white);
}

.quick-path > h2 {
  margin-bottom: var(--space-md);
}

.path-steps {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--space-md);
  counter-reset: path-counter;
  margin-bottom: var(--space-md);
}

.path-steps li {
  counter-increment: path-counter;
  position: relative;
  padding: var(--space-md);
  background-color: var(--color-paper);
  border: 1px solid var(--color-hairline);
  border-radius: var(--radius-md);
}

.path-steps li::before {
  content: "0" counter(path-counter);
  font-family: var(--font-serif);
  font-size: 24px;
  font-weight: 700;
  color: var(--color-accent);
  display: block;
  margin-bottom: 8px;
}

.path-steps li p {
  font-size: 14px;
  color: var(--color-text-soft);
  margin-bottom: 6px;
  line-height: 1.7;
}

.path-steps li p strong {
  display: block;
  font-family: var(--font-serif);
  font-size: 16px;
  color: var(--color-ink);
  margin-bottom: 6px;
}

.path-steps li a {
  font-size: 14px;
  font-weight: 700;
  color: var(--color-teal);
  min-height: 44px;
  display: inline-flex;
  align-items: center;
}

.path-final {
  text-align: center;
  font-size: 15px;
  color: var(--color-text-soft);
  padding-top: var(--space-sm);
  border-top: 1px solid var(--color-hairline);
  margin-bottom: 0;
}

.path-final a {
  display: inline-block;
  margin: 0 8px;
  font-weight: 700;
  min-height: 44px;
  line-height: 44px;
  padding: 0 4px;
}

/* ============================================================
   11. fenlei · 题材分类页
   ============================================================ */

/* ---- 题材轴总览 ---- */

.section-overview {
  margin-bottom: var(--space-xl);
}

.section-overview > h2,
.section-table > h2,
.section-principle > h2 {
  font-size: 22px;
  margin-bottom: var(--space-sm);
  padding-bottom: 8px;
  border-bottom: 2px solid var(--color-ink);
}

.section-lead {
  font-size: 15px;
  color: var(--color-text-soft);
  margin-bottom: var(--space-md);
  max-width: 70ch;
}

.overview-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--space-md);
}

.overview-item {
  background-color: var(--color-white);
  border: 1px solid var(--color-hairline);
  border-radius: var(--radius-md);
  overflow: hidden;
  display: flex;
  flex-direction: column;
}

.overview-text {
  padding: var(--space-sm) var(--space-sm) 0;
  flex: 1;
}

.overview-text h3 {
  font-size: 17px;
  margin-bottom: 6px;
}

.overview-text p {
  font-size: 14px;
  color: var(--color-text-soft);
  line-height: 1.7;
  margin-bottom: 10px;
}

.overview-figure {
  padding: 0 var(--space-sm) var(--space-sm);
}

.overview-figure img {
  width: 100%;
  aspect-ratio: 16 / 10;
  object-fit: cover;
  border-radius: var(--radius-sm);
  border: 1px solid var(--color-hairline);
}

.overview-figure figcaption {
  font-size: 12px;
  margin-top: 6px;
}

/* ---- 标签速查表 ---- */

.section-table {
  margin-bottom: var(--space-xl);
}

.axis-block {
  margin-bottom: var(--space-lg);
}

.axis-block > h3 {
  font-size: 18px;
  margin-bottom: var(--space-sm);
  padding-left: 12px;
  border-left: 4px solid var(--color-accent);
  line-height: 1.4;
}

.axis-block .table-figure {
  margin-bottom: var(--space-sm);
}

.axis-block .table-figure img {
  width: 100%;
  max-height: 220px;
  object-fit: cover;
  border-radius: var(--radius-sm);
  border: 1px solid var(--color-hairline);
}

.table-scroll {
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
}

.tag-table {
  min-width: 620px;
}

.tag-table th {
  font-size: 14px;
}

.tag-table td {
  font-size: 14px;
}

.tag-table td:first-child {
  font-weight: 700;
  white-space: nowrap;
}

/* ---- 归类原则 ---- */

.section-principle {
  margin-bottom: var(--space-xl);
}

.principle-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-md);
  margin-bottom: var(--space-md);
}

.principle-item {
  background-color: var(--color-white);
  border: 1px solid var(--color-hairline);
  border-radius: var(--radius-md);
  padding: var(--space-md);
  border-top: 3px solid var(--color-teal);
}

.principle-item:last-child {
  border-top-color: var(--color-accent);
}

.principle-item h3 {
  font-size: 17px;
  margin-bottom: 8px;
}

.principle-item p {
  font-size: 14px;
  color: var(--color-text-soft);
  line-height: 1.75;
  margin-bottom: 0;
}

.principle-footer {
  background-color: var(--color-white);
  border: 1px solid var(--color-hairline);
  border-radius: var(--radius-md);
  padding: var(--space-sm) var(--space-md);
}

.principle-footer p {
  font-size: 14px;
  color: var(--color-text-soft);
  margin-bottom: 0;
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 6px;
}

.principle-footer a {
  font-weight: 700;
  min-height: 44px;
  display: inline-flex;
  align-items: center;
  padding: 0 4px;
}

/* ---- 相关链接 ---- */

.related-links {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 10px;
  padding: var(--space-sm) var(--space-md);
  background-color: var(--color-white);
  border: 1px solid var(--color-hairline);
  border-radius: var(--radius-md);
  margin-bottom: var(--space-lg);
}

.related-links-label {
  font-size: 13px;
  font-weight: 700;
  color: var(--color-text-soft);
  margin-right: 4px;
  flex-shrink: 0;
}

.related-links-item {
  display: inline-block;
  padding: 6px 14px;
  font-size: 14px;
  background-color: var(--color-paper);
  border: 1px solid var(--color-hairline);
  border-radius: 999px;
  color: var(--color-ink);
  transition: border-color 0.2s ease, color 0.2s ease;
}

.related-links-item:hover {
  border-color: var(--color-accent);
  color: var(--color-accent);
  text-decoration: none;
}

/* ============================================================
   12. zhuanti · 策展专题页
   ============================================================ */

.topic-intro {
  margin-bottom: var(--space-lg);
}

.topic-intro h2 {
  font-size: 20px;
  margin-bottom: 8px;
}

.topic-intro p {
  font-size: 15px;
  color: var(--color-text-soft);
  line-height: 1.8;
  max-width: 70ch;
}

.topic-block {
  background-color: var(--color-white);
  border: 1px solid var(--color-hairline);
  border-radius: var(--radius-md);
  padding: var(--space-lg) var(--space-md);
  margin-bottom: var(--space-lg);
}

.topic-head {
  display: flex;
  align-items: flex-start;
  gap: var(--space-sm);
  border-bottom: 1px solid var(--color-hairline);
  padding-bottom: var(--space-sm);
  margin-bottom: var(--space-sm);
}

.topic-index {
  font-family: var(--font-serif);
  font-size: 28px;
  font-weight: 700;
  color: var(--color-accent);
  line-height: 1.2;
  flex-shrink: 0;
  min-width: 48px;
}

.topic-title-wrap h2 {
  font-size: 21px;
  margin-bottom: 4px;
}

.topic-subtitle {
  font-size: 14px;
  color: var(--color-text-soft);
  margin-bottom: 0;
}

.topic-block > p {
  font-size: 15px;
  color: var(--color-text-soft);
  line-height: 1.8;
  margin-bottom: 10px;
  max-width: 72ch;
}

.topic-media {
  margin: var(--space-sm) 0;
}

.topic-figure img {
  width: 100%;
  aspect-ratio: 16 / 7;
  object-fit: cover;
  border-radius: var(--radius-sm);
  border: 1px solid var(--color-hairline);
}

.topic-figure figcaption {
  font-size: 13px;
}

.topic-compare {
  margin-top: var(--space-sm);
}

.topic-compare h3 {
  font-size: 16px;
  margin-bottom: 10px;
}

.topic-compare table {
  font-size: 14px;
  min-width: 560px;
}

.topic-compare td {
  font-size: 14px;
}

.topic-compare .table-scroll {
  margin-bottom: var(--space-sm);
}

.topic-conclusion {
  background-color: var(--color-paper);
  border-left: 3px solid var(--color-accent);
  padding: 10px var(--space-sm);
  margin-top: var(--space-sm);
  font-size: 15px;
}

.topic-conclusion strong {
  display: block;
  font-family: var(--font-serif);
  font-size: 16px;
  margin-bottom: 4px;
}

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

.topic-note {
  font-size: 13px;
  color: var(--color-text-soft);
  background-color: var(--color-paper-deep);
  padding: 10px var(--space-sm);
  border-radius: var(--radius-sm);
  margin-top: 10px;
  line-height: 1.6;
  margin-bottom: 0;
}

/* ---- 来源与口径注释 ---- */

.source-note {
  background-color: var(--color-paper-deep);
  border: 1px solid var(--color-hairline);
  border-radius: var(--radius-md);
  padding: var(--space-md);
  margin-bottom: var(--space-lg);
}

.source-note h2 {
  font-size: 16px;
  margin-bottom: 10px;
  color: var(--color-ink);
}

.source-note p {
  font-size: 13px;
  color: var(--color-text-soft);
  line-height: 1.7;
  margin-bottom: 6px;
}

.source-note p:last-child {
  margin-bottom: 0;
}

/* ---- 专题辅助 aside ---- */

.topic-aside {
  position: sticky;
  top: calc(var(--header-h) + 16px);
}

.aside-card {
  background-color: var(--color-white);
  border: 1px solid var(--color-hairline);
  border-radius: var(--radius-md);
  padding: var(--space-md);
  margin-bottom: var(--space-md);
}

.aside-card h2 {
  font-size: 17px;
  margin-bottom: 8px;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--color-hairline);
}

.aside-card p {
  font-size: 14px;
  color: var(--color-text-soft);
  line-height: 1.7;
  margin-bottom: 10px;
}

.aside-links li {
  margin-bottom: 6px;
}

.aside-links li a {
  display: inline-flex;
  align-items: center;
  font-size: 14px;
  font-weight: 700;
  color: var(--color-teal);
  min-height: 40px;
  padding: 0 4px;
}

.aside-links li a:hover {
  color: var(--color-accent);
}

/* ============================================================
   13. guanzhu · 编辑观察页
   ============================================================ */

.observe-intro {
  margin-bottom: var(--space-lg);
}

.observe-intro > h2,
.observe-groups > h2,
.observe-boundary > h2,
.observe-entries > h2 {
  font-size: 20px;
  margin-bottom: var(--space-sm);
  padding-bottom: 8px;
  border-bottom: 2px solid var(--color-ink);
}

.observe-intro > p {
  font-size: 15px;
  color: var(--color-text-soft);
  line-height: 1.8;
  margin-bottom: var(--space-sm);
  max-width: 70ch;
}

.observe-criteria-list {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--space-sm);
}

.observe-criteria-list li {
  background-color: var(--color-white);
  border: 1px solid var(--color-hairline);
  border-radius: var(--radius-md);
  padding: var(--space-sm);
}

.observe-criteria-list li h3 {
  font-size: 15px;
  margin-bottom: 6px;
  color: var(--color-accent);
}

.observe-criteria-list li p {
  font-size: 13px;
  color: var(--color-text-soft);
  line-height: 1.7;
  margin-bottom: 0;
}

/* ---- 观察分组 ---- */

.observe-groups {
  margin-bottom: var(--space-lg);
}

.observe-lead-figure {
  margin-bottom: var(--space-md);
}

.observe-lead-figure img {
  width: 100%;
  aspect-ratio: 21 / 6;
  object-fit: cover;
  border-radius: var(--radius-md);
  border: 1px solid var(--color-hairline);
}

.observe-lead-figure figcaption {
  text-align: center;
}

.observe-group-list {
  display: flex;
  flex-direction: column;
  gap: var(--space-md);
}

.observe-item {
  background-color: var(--color-white);
  border: 1px solid var(--color-hairline);
  border-radius: var(--radius-md);
  padding: var(--space-md);
  border-left: 4px solid var(--color-teal);
}

.observe-item-2 {
  border-left-color: var(--color-accent);
}

.observe-item-3 {
  border-left-color: var(--color-ink);
}

.observe-item-head {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  margin-bottom: 10px;
}

.observe-index {
  font-family: var(--font-serif);
  font-size: 22px;
  font-weight: 700;
  color: var(--color-accent);
  flex-shrink: 0;
}

.observe-item-head h3 {
  font-size: 18px;
  margin-bottom: 0;
}

.observe-item-desc {
  font-size: 15px;
  color: var(--color-text-soft);
  line-height: 1.8;
  margin-bottom: 10px;
}

.observe-item-reason,
.observe-item-fit {
  font-size: 14px;
  line-height: 1.7;
  margin-bottom: 6px;
  color: var(--color-ink);
}

.observe-item-reason strong,
.observe-item-fit strong {
  font-weight: 700;
  color: var(--color-teal);
}

.observe-item-fit strong {
  color: var(--color-accent);
}

/* ---- 口径边界 ---- */

.observe-boundary {
  background-color: var(--color-white);
  border: 1px solid var(--color-hairline);
  border-radius: var(--radius-md);
  padding: var(--space-md);
  margin-bottom: var(--space-lg);
}

.observe-boundary p {
  font-size: 14px;
  color: var(--color-text-soft);
  line-height: 1.75;
  margin-bottom: 8px;
}

.observe-boundary p:last-child {
  margin-bottom: 0;
}

/* ---- 配套入口 ---- */

.observe-entries {
  margin-bottom: var(--space-lg);
}

.observe-entry-links {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-sm);
}

.entry-link {
  display: inline-flex;
  align-items: center;
  padding: 10px 22px;
  font-size: 14px;
  font-weight: 700;
  background-color: var(--color-white);
  border: 1px solid var(--color-ink);
  border-radius: var(--radius-sm);
  color: var(--color-ink);
  min-height: 44px;
  transition: background-color 0.2s ease, color 0.2s ease;
}

.entry-link:hover {
  background-color: var(--color-ink);
  color: var(--color-paper);
  text-decoration: none;
}

/* ---- 观察 aside ---- */

.observe-aside {
  position: sticky;
  top: calc(var(--header-h) + 16px);
}

.criteria-card-list {
  display: block;
}

.criteria-card-item {
  padding: 10px 0;
  border-bottom: 1px solid var(--color-hairline);
}

.criteria-card-item:last-child {
  border-bottom: none;
}

.criteria-card-item dt {
  font-family: var(--font-serif);
  font-size: 15px;
  font-weight: 700;
  color: var(--color-accent);
  margin-bottom: 4px;
}

.criteria-card-item dd {
  font-size: 13px;
  color: var(--color-text-soft);
  line-height: 1.7;
  margin: 0;
}

.aside-note {
  font-size: 13px;
  color: var(--color-text-soft);
  background-color: var(--color-paper);
  border: 1px solid var(--color-hairline);
  border-radius: var(--radius-sm);
  padding: 10px;
  line-height: 1.6;
  margin-top: var(--space-sm);
  margin-bottom: 0;
}

/* ============================================================
   14. zhinan · 阅读指南页
   ============================================================ */

.content-block {
  width: 100%;
}

.guide-steps {
  margin-bottom: var(--space-lg);
}

.guide-steps > h2,
.relation-table-block > h2 {
  font-size: 20px;
  margin-bottom: var(--space-sm);
  padding-bottom: 8px;
  border-bottom: 2px solid var(--color-ink);
}

.guide-steps > .section-intro,
.relation-table-block > .section-intro {
  font-size: 15px;
  color: var(--color-text-soft);
  margin-bottom: var(--space-md);
}

.guide-step {
  background-color: var(--color-white);
  border: 1px solid var(--color-hairline);
  border-radius: var(--radius-md);
  padding: var(--space-md);
  margin-bottom: var(--space-md);
  position: relative;
}

.step-heading {
  display: flex;
  align-items: flex-start;
  gap: var(--space-sm);
  margin-bottom: var(--space-sm);
  padding-bottom: 10px;
  border-bottom: 1px solid var(--color-hairline);
}

.step-number {
  font-family: var(--font-serif);
  font-size: 30px;
  font-weight: 700;
  color: var(--color-accent);
  line-height: 1.2;
  flex-shrink: 0;
  min-width: 52px;
  text-align: left;
}

.step-title-wrap h3 {
  font-size: 19px;
  margin-bottom: 4px;
}

.step-title-wrap p {
  font-size: 14px;
  color: var(--color-text-soft);
  margin-bottom: 0;
}

.step-content p {
  font-size: 15px;
  color: var(--color-text-soft);
  line-height: 1.8;
  margin-bottom: 10px;
  max-width: 68ch;
}

.step-figure {
  margin: var(--space-sm) 0;
}

.step-figure img {
  width: 100%;
  aspect-ratio: 16 / 7;
  object-fit: cover;
  border-radius: var(--radius-sm);
  border: 1px solid var(--color-hairline);
}

.step-figure figcaption {
  font-size: 13px;
}

/* ---- 栏目关系表 ---- */

.relation-table-block {
  margin-bottom: var(--space-lg);
}

.relation-table {
  min-width: 640px;
}

.relation-table th {
  font-size: 14px;
}

.relation-table td {
  font-size: 14px;
}

.table-footnote {
  font-size: 13px;
  color: var(--color-text-soft);
  margin-top: 8px;
  font-style: italic;
}

/* ---- 完成检查 aside ---- */

.guide-aside {
  position: sticky;
  top: calc(var(--header-h) + 16px);
}

.checklist-card .aside-intro,
.entry-card .aside-intro {
  font-size: 14px;
  color: var(--color-text-soft);
  line-height: 1.6;
  margin-bottom: var(--space-sm);
}

.check-list li {
  display: flex;
  align-items: flex-start;
  gap: 10px;
  padding: 8px 0;
  border-bottom: 1px solid var(--color-hairline);
  font-size: 14px;
  line-height: 1.6;
  color: var(--color-ink);
}

.check-list li:last-child {
  border-bottom: none;
}

.check-box {
  display: inline-block;
  width: 18px;
  height: 18px;
  border: 1px solid var(--color-ink);
  border-radius: var(--radius-sm);
  flex-shrink: 0;
  margin-top: 3px;
  background-color: var(--color-white);
}

.entry-list li {
  margin-bottom: 4px;
}

.entry-list li a {
  display: inline-flex;
  align-items: center;
  min-height: 40px;
  padding: 0 4px;
  font-size: 14px;
  font-weight: 700;
  color: var(--color-teal);
}

.entry-list li a:hover {
  color: var(--color-accent);
}

/* ============================================================
   15. wenda · 读者问答页
   ============================================================ */

/* ---- 问题分类 aside ---- */

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

.category-nav-block {
  background-color: var(--color-white);
  border: 1px solid var(--color-hairline);
  border-radius: var(--radius-md);
  padding: var(--space-md);
  margin-bottom: var(--space-md);
}

.category-nav-block h2,
.guide-block h2 {
  font-size: 17px;
  margin-bottom: 10px;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--color-hairline);
}

.category-nav-list li {
  margin-bottom: 4px;
}

.category-nav-list li a {
  display: block;
  padding: 8px 10px;
  font-size: 14px;
  color: var(--color-ink);
  border-left: 2px solid transparent;
  line-height: 1.5;
}

.category-nav-list li a:hover {
  color: var(--color-accent);
  background-color: var(--color-paper);
  border-left-color: var(--color-accent);
  text-decoration: none;
}

.guide-block {
  background-color: var(--color-white);
  border: 1px solid var(--color-hairline);
  border-radius: var(--radius-md);
  padding: var(--space-md);
}

.guide-block p {
  font-size: 14px;
  color: var(--color-text-soft);
  line-height: 1.7;
  margin-bottom: 8px;
}

.guide-block p:last-child {
  margin-bottom: 0;
}

/* ---- 问答主内容 ---- */

.page-content {
  min-width: 0;
  width: 100%;
}

.page-content .breadcrumb {
  margin-top: 0;
}

/* ---- 热门问题 ---- */

.hot-questions {
  background-color: var(--color-white);
  border: 1px solid var(--color-hairline);
  border-radius: var(--radius-md);
  padding: var(--space-md);
  margin-bottom: var(--space-lg);
}

.hot-questions-head h2 {
  font-size: 19px;
  margin-bottom: 4px;
}

.hot-questions-head p {
  font-size: 14px;
  color: var(--color-text-soft);
  margin-bottom: var(--space-sm);
}

.hot-questions-figure {
  margin-bottom: var(--space-sm);
}

.hot-questions-figure img {
  width: 100%;
  aspect-ratio: 21 / 6;
  object-fit: cover;
  border-radius: var(--radius-sm);
  border: 1px solid var(--color-hairline);
}

.hot-question-list {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-sm);
}

.hot-question-item {
  background-color: var(--color-paper);
  border: 1px solid var(--color-hairline);
  border-radius: var(--radius-sm);
  padding: var(--space-sm);
}

.hot-question-item h3 {
  font-size: 15px;
  margin-bottom: 6px;
  color: var(--color-accent);
}

.hot-question-item p {
  font-size: 14px;
  color: var(--color-text-soft);
  line-height: 1.7;
  margin-bottom: 0;
}

/* ---- 问答分组 ---- */

.qa-group {
  margin-bottom: var(--space-lg);
}

.qa-group > h2 {
  font-size: 19px;
  margin-bottom: 6px;
  padding-bottom: 8px;
  border-bottom: 2px solid var(--color-ink);
}

.group-desc {
  font-size: 14px;
  color: var(--color-text-soft);
  margin-bottom: var(--space-sm);
  line-height: 1.7;
}

.qa-list {
  display: block;
}

.qa-item {
  background-color: var(--color-white);
  border: 1px solid var(--color-hairline);
  border-radius: var(--radius-sm);
  margin-bottom: 10px;
}

.qa-item summary {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-sm);
  padding: 14px var(--space-md);
  font-size: 15px;
  font-weight: 700;
  color: var(--color-ink);
  cursor: pointer;
  list-style: none;
  line-height: 1.5;
  min-height: 48px;
}

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

.qa-item summary::after {
  content: "+";
  font-size: 20px;
  font-weight: 700;
  color: var(--color-accent);
  flex-shrink: 0;
  transition: transform 0.2s ease;
}

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

.qa-item[open] summary {
  border-bottom: 1px solid var(--color-hairline);
}

.qa-answer {
  padding: var(--space-sm) var(--space-md);
}

.qa-answer p {
  font-size: 14px;
  color: var(--color-text-soft);
  line-height: 1.8;
  margin-bottom: 8px;
}

.qa-answer p:last-child {
  margin-bottom: 0;
}

.qa-answer a {
  font-weight: 700;
  color: var(--color-teal);
  text-decoration: underline;
}

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

/* ============================================================
   16. guifan · 版权与反馈页
   ============================================================ */

/* ---- 前置目录 ---- */

.toc-nav {
  background-color: var(--color-white);
  border: 1px solid var(--color-hairline);
  border-radius: var(--radius-md);
  padding: var(--space-sm) var(--space-md);
  margin-bottom: var(--space-lg);
}

.toc-title {
  font-size: 15px;
  margin-bottom: 8px;
  color: var(--color-text-soft);
}

.toc-nav ul {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.toc-nav ul li a {
  display: inline-block;
  padding: 6px 16px;
  font-size: 14px;
  background-color: var(--color-paper);
  border: 1px solid var(--color-hairline);
  border-radius: 999px;
  color: var(--color-ink);
  min-height: 36px;
  line-height: 1.4;
}

.toc-nav ul li a:hover {
  border-color: var(--color-accent);
  color: var(--color-accent);
  text-decoration: none;
}

/* ---- 通用条款章节 ---- */

.rules-section,
.copyright-section,
.feedback-section {
  background-color: var(--color-white);
  border: 1px solid var(--color-hairline);
  border-radius: var(--radius-md);
  padding: var(--space-lg) var(--space-md);
  margin-bottom: var(--space-lg);
}

.section-title {
  font-size: 20px;
  margin-bottom: var(--space-sm);
  padding-bottom: 8px;
  border-bottom: 2px solid var(--color-ink);
}

.section-lead {
  font-size: 15px;
  color: var(--color-text-soft);
  margin-bottom: var(--space-md);
  line-height: 1.8;
}

/* ---- 站内公约列表 ---- */

.rules-list {
  display: block;
}

.rules-list li {
  padding: 12px 0;
  border-bottom: 1px solid var(--color-hairline);
  font-size: 15px;
  line-height: 1.7;
  padding-left: 24px;
  position: relative;
}

.rules-list li::before {
  content: "";
  position: absolute;
  left: 4px;
  top: 20px;
  width: 6px;
  height: 6px;
  background-color: var(--color-accent);
  border-radius: 50%;
}

.rules-list li:last-child {
  border-bottom: none;
}

/* ---- 版权素材边界 ---- */

.copyright-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-lg);
  align-items: start;
}

.copyright-text h3 {
  font-size: 16px;
  margin-bottom: 8px;
  color: var(--color-teal);
}

.copyright-text p {
  font-size: 14px;
  color: var(--color-text-soft);
  line-height: 1.8;
  margin-bottom: 8px;
}

.copyright-figure {
  grid-column: 1 / -1;
  margin-top: var(--space-sm);
}

.copyright-figure img {
  width: 100%;
  aspect-ratio: 21 / 7;
  object-fit: cover;
  border-radius: var(--radius-sm);
  border: 1px solid var(--color-hairline);
}

.copyright-figure figcaption {
  text-align: center;
}

/* ---- 反馈步骤 ---- */

.feedback-steps {
  counter-reset: feedback-counter;
}

.feedback-steps li {
  counter-increment: feedback-counter;
  padding: 12px 0 12px 56px;
  border-bottom: 1px solid var(--color-hairline);
  position: relative;
}

.feedback-steps li:last-child {
  border-bottom: none;
}

.feedback-steps li::before {
  content: counter(feedback-counter);
  position: absolute;
  left: 0;
  top: 12px;
  width: 36px;
  height: 36px;
  background-color: var(--color-accent);
  color: var(--color-white);
  font-family: var(--font-serif);
  font-size: 18px;
  font-weight: 700;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-sm);
}

.feedback-steps li h3 {
  font-size: 16px;
  margin-bottom: 4px;
}

.feedback-steps li p {
  font-size: 14px;
  color: var(--color-text-soft);
  line-height: 1.7;
  margin-bottom: 0;
}

.feedback-note {
  background-color: var(--color-paper);
  border-left: 3px solid var(--color-teal);
  padding: 10px var(--space-sm);
  margin-top: var(--space-sm);
}

.feedback-note p {
  font-size: 14px;
  color: var(--color-text-soft);
  line-height: 1.7;
  margin-bottom: 0;
}

/* ---- 相关栏目导航 ---- */

.related-links h2.section-title {
  font-size: 17px;
  border-bottom: none;
  padding-bottom: 0;
}

.related-links p {
  font-size: 14px;
  color: var(--color-text-soft);
  margin-bottom: var(--space-sm);
}

.related-links ul {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.related-links ul li a {
  display: inline-flex;
  align-items: center;
  padding: 8px 18px;
  font-size: 14px;
  background-color: var(--color-white);
  border: 1px solid var(--color-hairline);
  border-radius: 999px;
  color: var(--color-ink);
  min-height: 40px;
}

.related-links ul li a:hover {
  border-color: var(--color-accent);
  color: var(--color-accent);
  text-decoration: none;
}

/* ============================================================
   17. 404 页面
   ============================================================ */

.error-main {
  display: flex;
  align-items: center;
  justify-content: center;
  padding: var(--space-xl) var(--space-md);
  min-height: calc(100vh - var(--header-h) - 300px);
}

.error-panel {
  background-color: var(--color-white);
  border: 1px solid var(--color-hairline);
  border-radius: var(--radius-md);
  padding: var(--space-xl) var(--space-lg);
  max-width: 620px;
  width: 100%;
  text-align: center;
}

.error-code {
  font-family: var(--font-serif);
  font-size: 72px;
  font-weight: 700;
  color: var(--color-accent);
  line-height: 1.1;
  margin-bottom: var(--space-sm);
}

.error-copy h1 {
  font-size: 24px;
  margin-bottom: var(--space-sm);
}

.error-copy p {
  font-size: 15px;
  color: var(--color-text-soft);
  line-height: 1.8;
  margin-bottom: 8px;
}

.error-actions {
  display: flex;
  justify-content: center;
  flex-wrap: wrap;
  gap: var(--space-sm);
  margin-top: var(--space-md);
}

.error-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 12px 28px;
  font-size: 15px;
  font-weight: 700;
  background-color: var(--color-accent);
  color: var(--color-white);
  border: 1px solid var(--color-accent);
  border-radius: var(--radius-sm);
  min-height: 44px;
}

.error-btn:hover {
  background-color: var(--color-accent-deep);
  color: var(--color-white);
  text-decoration: none;
}

.error-actions a:not(.error-btn) {
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  padding: 0 12px;
  font-weight: 700;
  color: var(--color-teal);
}

.error-actions a:not(.error-btn):hover {
  color: var(--color-accent);
}

/* ============================================================
   18. Responsive / 响应式
   ============================================================ */

@media (max-width: 1024px) {

  .hero-section {
    grid-template-columns: 1fr;
    padding: var(--space-lg) var(--space-md);
  }

  .hero-copy {
    order: 1;
  }

  .hero-visual {
    order: 2;
  }

  .tag-group-grid {
    grid-template-columns: 1fr;
    gap: var(--space-sm);
  }

  .sidebar-left {
    grid-template-columns: 1fr;
    gap: var(--space-md);
  }

  .sidebar-left > .sidebar-nav,
  .sidebar-left > .page-aside,
  .sidebar-left .page-layout > .page-aside {
    grid-column: 1;
    position: static;
    order: 2;
  }

  .sidebar-left > .site-main,
  .sidebar-left > .page-content,
  .sidebar-left .page-layout > .page-content {
    grid-column: 1;
    order: 1;
  }

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

  .sidebar-right {
    grid-template-columns: 1fr;
  }

  .sidebar-right > .site-main {
    grid-column: 1;
  }

  .sidebar-right > .guide-aside {
    grid-column: 1;
    position: static;
  }

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

  .page-layout.layout-shell > .site-main {
    grid-column: 1;
  }

  .page-layout.layout-shell > .observe-aside {
    grid-column: 1;
    position: static;
  }

  .layout-shell:has(.content-column) {
    grid-template-columns: 1fr;
  }

  .content-column {
    grid-column: 1;
  }

  .topic-aside {
    grid-column: 1;
    position: static;
  }

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

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

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

  .copyright-figure {
    grid-column: 1;
  }

}

@media (max-width: 768px) {

  :root {
    --header-h: 56px;
  }

  body {
    font-size: var(--font-size-body-mobile);
  }

  h1 {
    font-size: 26px;
  }

  h2 {
    font-size: 19px;
  }

  .header-inner {
    padding: 0 var(--space-sm);
  }

  .nav-toggle {
    display: flex;
  }

  .site-nav {
    position: absolute;
    top: var(--header-h);
    left: 0;
    right: 0;
    background-color: var(--color-white);
    border-bottom: 1px solid var(--color-hairline);
    box-shadow: 0 8px 16px rgba(31, 36, 33, 0.06);
  }

  .site-nav .nav-list {
    display: none;
    flex-direction: column;
    align-items: stretch;
    padding: var(--space-xs) var(--space-sm);
    gap: 0;
  }

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

  .site-nav .nav-list li {
    border-bottom: 1px solid var(--color-hairline);
  }

  .site-nav .nav-list li:last-child {
    border-bottom: none;
  }

  .site-nav .nav-list a {
    padding: 14px 12px;
    font-size: 16px;
    border-radius: 0;
  }

  .site-nav .nav-list a.is-current {
    background-color: var(--color-paper);
  }

  .hero-section {
    padding: var(--space-lg) var(--space-sm);
    gap: var(--space-md);
  }

  .hero-actions {
    flex-direction: column;
    align-items: flex-start;
  }

  .hero-actions .btn-primary,
  .hero-actions .btn-secondary {
    width: 100%;
    max-width: 360px;
  }

  .section-block {
    padding: var(--space-lg) var(--space-sm);
  }

  .info-grid {
    grid-template-columns: 1fr;
    gap: var(--space-md);
  }

  .dual-modules {
    grid-template-columns: 1fr;
  }

  .dual-modules > h2 {
    grid-column: 1;
  }

  .support-grid {
    grid-template-columns: 1fr;
    gap: var(--space-sm);
  }

  .path-steps {
    grid-template-columns: 1fr;
    gap: var(--space-sm);
  }

  .overview-grid {
    grid-template-columns: 1fr;
    gap: var(--space-sm);
  }

  .principle-grid {
    grid-template-columns: 1fr;
    gap: var(--space-sm);
  }

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

  .observe-entry-links {
    flex-direction: column;
    align-items: stretch;
  }

  .entry-link {
    justify-content: center;
  }

  .footer-links {
    grid-template-columns: 1fr 1fr;
    gap: var(--space-md);
  }

  .footer-bottom p {
    font-size: 12px;
  }

  .breadcrumb {
    padding: 12px 0;
    margin-bottom: 12px;
    font-size: 13px;
  }

  .page-header {
    padding: var(--space-sm) 0 var(--space-md);
    margin-bottom: var(--space-md);
  }

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

  .page-description {
    font-size: 15px;
  }

  .inner-main {
    padding: 0 var(--space-sm);
  }

  .layout-shell {
    padding: 0 var(--space-sm);
  }

  .topic-block {
    padding: var(--space-md) var(--space-sm);
  }

  .topic-head {
    flex-direction: column;
    gap: 4px;
  }

  .topic-index {
    font-size: 22px;
  }

  .topic-compare table {
    min-width: 520px;
  }

  .step-heading {
    flex-direction: column;
    gap: 4px;
  }

  .step-number {
    font-size: 24px;
  }

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

  .qa-item summary {
    padding: 12px var(--space-sm);
    font-size: 14px;
  }

  .qa-answer {
    padding: 12px var(--space-sm);
  }

  .error-main {
    padding: var(--space-lg) var(--space-sm);
  }

  .error-panel {
    padding: var(--space-lg) var(--space-md);
  }

  .error-code {
    font-size: 56px;
  }

  .rules-section,
  .copyright-section,
  .feedback-section {
    padding: var(--space-md) var(--space-sm);
  }

  .feedback-steps li {
    padding-left: 48px;
  }

  .feedback-steps li::before {
    width: 32px;
    height: 32px;
    font-size: 16px;
  }

  .toc-nav ul {
    flex-direction: column;
    gap: 4px;
  }

  .toc-nav ul li a {
    display: block;
    text-align: center;
  }

}

@media (max-width: 480px) {

  h1 {
    font-size: 23px;
  }

  h2 {
    font-size: 18px;
  }

  .brand-link {
    font-size: 20px;
  }

  .hero-lead {
    font-size: 16px;
  }

  .section-block > h2 {
    font-size: 20px;
  }

  .footer-links {
    grid-template-columns: 1fr;
    gap: var(--space-sm);
  }

  .footer-col h4 {
    margin-bottom: 8px;
  }

  .footer-col ul {
    display: none;
  }

  .footer-col:first-child ul {
    display: block;
  }

  .dual-module h2 {
    font-size: 18px;
  }

  .support-card h3 {
    font-size: 16px;
  }

  .tag-group h3 {
    font-size: 17px;
  }

  .table-scroll {
    margin-right: calc(-1 * var(--space-sm));
    padding-right: var(--space-sm);
  }

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

  .topic-title-wrap h2 {
    font-size: 18px;
  }

  .step-title-wrap h3 {
    font-size: 17px;
  }

  .observe-item-head {
    flex-direction: column;
    gap: 2px;
  }

  .observe-index {
    font-size: 18px;
  }

  .related-links {
    flex-direction: column;
    align-items: flex-start;
    gap: 6px;
  }

  .related-links-label {
    margin-bottom: 4px;
  }

  .related-links ul {
    flex-direction: column;
    width: 100%;
  }

  .related-links ul li a {
    display: block;
    text-align: center;
    width: 100%;
  }

  .copyright-grid {
    gap: var(--space-sm);
  }

  .feedback-note {
    padding: 8px 12px;
  }

  .error-actions {
    flex-direction: column;
    align-items: stretch;
  }

  .error-actions a:not(.error-btn) {
    justify-content: center;
  }

}

/* ============================================================
   19. 动效增强（不影响初始可见性）
   ============================================================ */

@media (prefers-reduced-motion: no-preference) {

  .topic-block {
    transition: border-color 0.2s ease;
  }

  .topic-block:hover {
    border-color: #d5cfc2;
  }

  .tag-group {
    transition: border-color 0.2s ease;
  }

  .tag-group:hover {
    border-color: #d5cfc2;
  }

  .support-card {
    transition: transform 0.2s ease, box-shadow 0.2s ease;
  }

  .support-card:hover {
    transform: translateY(-2px);
  }

  .guide-step {
    transition: border-color 0.2s ease;
  }

  .guide-step:hover {
    border-color: #d5cfc2;
  }

  .qa-item summary:hover {
    background-color: var(--color-paper);
  }

  .qa-item[open] summary:hover {
    background-color: transparent;
  }

}