/* ==========================================================================
   基础层：变量、重置、排版、通用元素
   ========================================================================== */

:root {
  --paper: #F4EFE3;
  --paper-deep: #ECE5D5;
  --ink: #1D1B18;
  --ink-soft: #4A463F;
  --cinnabar: #B23A2F;
  --pine: #5F6B4F;
  --line: #D8D0BF;
  --white: #FBF8F0;

  --font-serif: "Songti SC", "SimSun", "Noto Serif SC", "Source Han Serif SC", serif;
  --font-sans: "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", "Noto Sans SC", "Source Han Sans SC", sans-serif;

  --shell-max: 1280px;
  --sidebar-w: 236px;
  --content-max: 920px;
  --gap: 40px;
  --radius: 6px;
}

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

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

body,
h1, h2, h3, h4,
p, figure, figcaption, blockquote,
dl, dd, ol, ul {
  margin: 0;
}

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

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

a {
  color: inherit;
  text-decoration: none;
}

button {
  font: inherit;
  color: inherit;
  background: none;
  border: 0;
  padding: 0;
  cursor: pointer;
}

.site-body {
  margin: 0;
  min-height: 100vh;
  background-color: var(--paper);
  color: var(--ink);
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.75;
  font-weight: 400;
  display: flex;
  flex-direction: column;
}

h1, h2, h3, h4 {
  font-family: var(--font-serif);
  font-weight: 700;
  line-height: 1.35;
  color: var(--ink);
}

p {
  color: var(--ink-soft);
}

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

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

.skip-link {
  position: absolute;
  top: -60px;
  left: 16px;
  z-index: 200;
  padding: 10px 18px;
  background: var(--ink);
  color: var(--white);
  border-radius: var(--radius);
  font-size: 14px;
}

.skip-link:focus {
  top: 12px;
  color: var(--white);
}

/* ==========================================================================
   布局层：页头、外壳、侧栏、主内容容器
   ========================================================================== */

.site-header {
  position: sticky;
  top: 0;
  z-index: 60;
  background-color: var(--paper);
  border-bottom: 1px solid var(--line);
}

.header-inner {
  max-width: var(--shell-max);
  margin: 0 auto;
  padding: 0 24px;
  height: 64px;
  display: flex;
  align-items: center;
  gap: 28px;
}

.brand {
  display: flex;
  align-items: baseline;
  gap: 12px;
  min-width: 0;
  flex-shrink: 0;
}

.brand-name {
  font-family: var(--font-serif);
  font-size: 22px;
  font-weight: 700;
  color: var(--ink);
  white-space: nowrap;
}

.brand-slogan {
  font-size: 12px;
  color: var(--pine);
  letter-spacing: 0;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.primary-nav {
  margin-left: auto;
  min-width: 0;
}

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

.nav-link {
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  padding: 0 12px;
  font-size: 14px;
  color: var(--ink-soft);
  border-bottom: 2px solid transparent;
  transition: color .18s ease, border-color .18s ease;
}

.nav-link:hover {
  color: var(--cinnabar);
}

.nav-link.is-current {
  color: var(--cinnabar);
  border-bottom-color: var(--cinnabar);
  font-weight: 500;
}

.menu-toggle {
  display: none;
  align-items: center;
  gap: 6px;
  min-height: 44px;
  min-width: 44px;
  padding: 0 12px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  font-size: 14px;
  color: var(--ink);
  background-color: var(--white);
}

/* 桌面外壳：侧栏在左，主内容在右 */
.layout-shell,
.page-layout {
  width: 100%;
  max-width: var(--shell-max);
  margin: 0 auto;
  padding: 28px 24px 56px;
  display: grid;
  grid-template-columns: var(--sidebar-w) minmax(0, 1fr);
  gap: var(--gap);
  align-items: start;
  flex: 1 0 auto;
}

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

/* 侧栏在各页使用不同类名，统一外观 */
.side-nav,
.site-sidebar,
.site-drawer {
  position: sticky;
  top: 92px;
  align-self: start;
  max-height: calc(100vh - 116px);
  overflow-y: auto;
  padding: 18px 16px;
  background-color: var(--white);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  font-size: 14px;
}

.side-nav-head,
.sidebar-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 10px;
  padding-bottom: 12px;
  margin-bottom: 12px;
  border-bottom: 1px solid var(--line);
}

.side-nav-title,
.sidebar-title {
  margin: 0;
  font-family: var(--font-serif);
  font-size: 14px;
  font-weight: 700;
  color: var(--ink);
  letter-spacing: .04em;
}

.drawer-close {
  display: none;
  min-height: 44px;
  min-width: 44px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  font-size: 13px;
  color: var(--ink-soft);
  background-color: var(--paper);
}

/* 侧栏分组：索引页、术语页、问题页、关于页使用按钮切换 */
.side-group {
  border-bottom: 1px solid var(--line);
  padding-bottom: 8px;
  margin-bottom: 8px;
}

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

.side-group-toggle,
.nav-group-toggle,
.group-toggle {
  display: flex;
  align-items: center;
  justify-content: space-between;
  width: 100%;
  min-height: 44px;
  padding: 0 4px;
  font-family: var(--font-serif);
  font-size: 13px;
  font-weight: 700;
  color: var(--pine);
  text-align: left;
}

.side-group-toggle::after,
.nav-group-toggle::after,
.group-toggle::after {
  content: "＋";
  font-size: 12px;
  color: var(--pine);
  margin-left: 8px;
}

.side-group-toggle[aria-expanded="true"]::after,
.nav-group-toggle[aria-expanded="true"]::after,
.group-toggle[aria-expanded="true"]::after {
  content: "－";
}

.side-group-heading,
.nav-group-title {
  margin: 0;
  padding: 10px 4px 6px;
  font-family: var(--font-serif);
  font-size: 13px;
  font-weight: 700;
  color: var(--pine);
}

.side-list,
.nav-group-list,
.group-list {
  display: flex;
  flex-direction: column;
  gap: 2px;
  padding-bottom: 6px;
}

.side-link,
.nav-group-list a,
.group-list a {
  display: flex;
  align-items: center;
  min-height: 40px;
  padding: 6px 10px;
  font-size: 14px;
  color: var(--ink-soft);
  border-left: 2px solid transparent;
  border-radius: 0 var(--radius) var(--radius) 0;
  transition: background-color .18s ease, color .18s ease;
}

.side-link:hover,
.nav-group-list a:hover,
.group-list a:hover {
  background-color: var(--paper-deep);
  color: var(--cinnabar);
}

.side-link.is-current,
.nav-group-list a.is-current,
.group-list a.is-current {
  color: var(--cinnabar);
  font-weight: 500;
  border-left-color: var(--cinnabar);
  background-color: var(--paper-deep);
}

/* 主内容区 */
.site-main {
  min-width: 0;
  width: 100%;
}

.inner-main {
  max-width: var(--content-max);
  width: 100%;
}

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

/* ==========================================================================
   组件层：面包屑、页面标题区、按钮、图注、通用链接
   ========================================================================== */

.breadcrumb {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 6px;
  padding: 0 0 14px;
  font-size: 13px;
  color: var(--ink-soft);
}

.breadcrumb a {
  color: var(--pine);
  min-height: 24px;
  display: inline-flex;
  align-items: center;
}

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

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

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

.page-header {
  padding: 0 0 18px;
  border-bottom: 1px solid var(--line);
  margin-bottom: 26px;
}

.page-title {
  font-size: 40px;
  font-weight: 700;
  line-height: 1.3;
  color: var(--ink);
}

.page-title-block,
.page-head {
  margin-bottom: 28px;
}

.page-kicker {
  margin-bottom: 6px;
  font-family: var(--font-serif);
  font-size: 13px;
  font-weight: 500;
  color: var(--cinnabar);
  letter-spacing: .06em;
}

.eyebrow {
  margin-bottom: 6px;
  font-family: var(--font-serif);
  font-size: 13px;
  font-weight: 500;
  color: var(--cinnabar);
  letter-spacing: .06em;
}

.page-lead {
  font-size: 16px;
  line-height: 1.8;
  color: var(--ink-soft);
  max-width: 72ch;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 46px;
  padding: 0 22px;
  border-radius: var(--radius);
  font-size: 15px;
  font-weight: 500;
  border: 1px solid transparent;
  transition: background-color .18s ease, color .18s ease, border-color .18s ease;
}

.btn-primary {
  background-color: var(--cinnabar);
  color: var(--white);
  border-color: var(--cinnabar);
}

.btn-primary:hover {
  background-color: #9A2F26;
  color: var(--white);
}

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

.btn-ghost:hover {
  border-color: var(--cinnabar);
  color: var(--cinnabar);
}

.inline-link {
  display: inline-flex;
  align-items: center;
  min-height: 40px;
  font-size: 14px;
  font-weight: 500;
  color: var(--cinnabar);
}

.inline-link::after {
  content: "→";
  margin-left: 6px;
  transition: transform .18s ease;
}

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

.figure-caption {
  margin-top: 8px;
  font-size: 13px;
  line-height: 1.7;
  color: var(--pine);
  border-left: 2px solid var(--line);
  padding-left: 10px;
}

/* 图片容器统一约束 */
.hero-figure,
.special-figure,
.overview-figure,
.principle-figure,
.media-figure,
.glossary-figure,
.faq-intro-figure,
.about-figure {
  margin: 0;
  width: 100%;
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background-color: var(--paper-deep);
}

.hero-figure img,
.special-figure img,
.overview-figure img,
.principle-figure img,
.media-figure img,
.glossary-figure img,
.faq-intro-figure img,
.about-figure img {
  width: 100%;
  height: auto;
  aspect-ratio: 16 / 10;
  object-fit: cover;
}

.hero-figure figcaption,
.special-figure figcaption,
.overview-figure figcaption,
.principle-figure figcaption,
.media-figure figcaption,
.glossary-figure figcaption,
.faq-intro-figure figcaption,
.about-figure figcaption {
  padding: 10px 12px;
  font-size: 13px;
  line-height: 1.7;
  color: var(--pine);
  background-color: var(--white);
  border-top: 1px solid var(--line);
}

/* ==========================================================================
   首页模块
   ========================================================================== */

/* 首屏档案台 */
.hero-desk {
  display: grid;
  grid-template-columns: minmax(0, 1.05fr) minmax(0, 1fr);
  gap: 36px;
  padding-bottom: 40px;
  border-bottom: 1px solid var(--line);
  margin-bottom: 44px;
}

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

.hero-kicker {
  font-family: var(--font-serif);
  font-size: 13px;
  font-weight: 500;
  color: var(--cinnabar);
  letter-spacing: .08em;
  margin-bottom: 12px;
}

.hero-text h1 {
  font-size: 40px;
  line-height: 1.28;
  margin-bottom: 16px;
}

.hero-lead {
  font-size: 16px;
  line-height: 1.85;
  color: var(--ink-soft);
  margin-bottom: 22px;
  max-width: 46ch;
}

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

.hero-index {
  min-width: 0;
  padding: 20px;
  background-color: var(--white);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.index-title {
  font-size: 20px;
  margin-bottom: 6px;
}

.index-note {
  font-size: 13px;
  color: var(--pine);
  margin-bottom: 14px;
}

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

.hero-index .topic-row {
  display: grid;
  grid-template-columns: 34px minmax(88px, 120px) minmax(0, 1fr) auto;
  align-items: center;
  gap: 10px;
  padding: 10px 4px;
  border-bottom: 1px solid var(--line);
  transition: background-color .18s ease;
}

.hero-index .topic-row:hover {
  background-color: var(--paper-deep);
}

.topic-no {
  font-family: var(--font-serif);
  font-size: 13px;
  font-weight: 700;
  color: var(--cinnabar);
}

.topic-name {
  font-family: var(--font-serif);
  font-size: 15px;
  font-weight: 500;
  color: var(--ink);
}

.topic-scope {
  font-size: 13px;
  line-height: 1.6;
  color: var(--ink-soft);
  min-width: 0;
}

.topic-link {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 32px;
  min-width: 44px;
  padding: 0 10px;
  font-size: 13px;
  color: var(--cinnabar);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background-color: var(--paper);
  white-space: nowrap;
}

.topic-link:hover {
  border-color: var(--cinnabar);
  background-color: var(--white);
}

/* 模块通用标题 */
.section-head {
  margin-bottom: 22px;
}

.section-head h2 {
  font-size: 26px;
  margin-bottom: 8px;
}

.section-desc {
  font-size: 15px;
  color: var(--ink-soft);
  max-width: 68ch;
}

/* 重点专题索引 */
.special-index {
  padding-bottom: 40px;
  border-bottom: 1px solid var(--line);
  margin-bottom: 44px;
}

.special-body {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 320px);
  gap: 32px;
  align-items: start;
}

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

.special-item {
  display: grid;
  grid-template-columns: 40px minmax(0, 1fr);
  grid-template-areas:
    "no name"
    "no summary"
    "no order"
    "no link";
  column-gap: 14px;
  padding: 18px 6px;
  border-bottom: 1px solid var(--line);
  transition: background-color .18s ease;
}

.special-item:hover {
  background-color: var(--paper-deep);
}

.special-no {
  grid-area: no;
  font-family: var(--font-serif);
  font-size: 15px;
  font-weight: 700;
  color: var(--cinnabar);
}

.special-name {
  grid-area: name;
  font-size: 18px;
  margin-bottom: 6px;
}

.special-summary {
  grid-area: summary;
  font-size: 14px;
  line-height: 1.75;
  margin-bottom: 6px;
}

.special-order {
  grid-area: order;
  font-size: 13px;
  color: var(--pine);
  margin-bottom: 4px;
}

.special-link {
  grid-area: link;
  display: inline-flex;
  align-items: center;
  min-height: 40px;
  font-size: 14px;
  font-weight: 500;
  color: var(--cinnabar);
}

.special-link::after {
  content: "→";
  margin-left: 6px;
}

.special-figure {
  position: sticky;
  top: 92px;
}

/* 新人阅读路径：三步轨道 */
.path-track {
  padding-bottom: 40px;
  border-bottom: 1px solid var(--line);
  margin-bottom: 44px;
}

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

.track-step {
  display: flex;
  flex-direction: column;
  gap: 8px;
  padding: 20px 18px;
  background-color: var(--white);
  border: 1px solid var(--line);
  border-top: 3px solid var(--cinnabar);
  border-radius: var(--radius);
  min-width: 0;
}

.track-no {
  font-family: var(--font-serif);
  font-size: 13px;
  font-weight: 700;
  color: var(--cinnabar);
  letter-spacing: .06em;
}

.track-action {
  font-size: 18px;
  line-height: 1.45;
}

.track-output {
  font-size: 14px;
  line-height: 1.75;
  color: var(--ink-soft);
  flex: 1 1 auto;
}

.track-link {
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  font-size: 14px;
  font-weight: 500;
  color: var(--cinnabar);
}

.track-link::after {
  content: "→";
  margin-left: 6px;
}

/* 术语速查 */
.glossary-quick {
  padding-bottom: 40px;
  border-bottom: 1px solid var(--line);
  margin-bottom: 44px;
}

.glossary-groups {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 20px;
}

.glossary-group {
  min-width: 0;
  padding: 18px;
  background-color: var(--white);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.group-name {
  font-size: 17px;
  padding-bottom: 10px;
  margin-bottom: 10px;
  border-bottom: 1px solid var(--line);
  color: var(--pine);
}

.glossary-items {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.glossary-items li {
  font-size: 14px;
  line-height: 1.7;
  color: var(--ink-soft);
}

.glossary-items li a {
  color: var(--ink);
  min-height: 24px;
  display: inline-flex;
  align-items: center;
}

.glossary-items li a:hover {
  color: var(--cinnabar);
}

.glossary-hint {
  margin-top: 14px;
  font-size: 13px;
  color: var(--pine);
}

/* 内容边界与纠错 */
.boundary {
  padding-bottom: 32px;
  border-bottom: 1px solid var(--line);
  margin-bottom: 32px;
}

.boundary-body {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 24px;
  margin-bottom: 28px;
}

.boundary-col {
  min-width: 0;
  padding: 18px 20px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background-color: var(--white);
}

.boundary-sub {
  font-size: 17px;
  margin-bottom: 10px;
  color: var(--ink);
}

.boundary-list {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

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

.boundary-list li::before {
  content: "·";
  position: absolute;
  left: 2px;
  top: 0;
  color: var(--cinnabar);
  font-weight: 700;
}

.fix-flow {
  padding: 20px;
  background-color: var(--paper-deep);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.fix-title {
  font-size: 17px;
  margin-bottom: 12px;
}

.fix-steps {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 16px;
  margin-bottom: 12px;
}

.fix-step {
  min-width: 0;
  font-size: 14px;
  line-height: 1.75;
  color: var(--ink-soft);
  padding-left: 34px;
  position: relative;
}

.fix-no {
  position: absolute;
  left: 0;
  top: 0;
  font-family: var(--font-serif);
  font-size: 13px;
  font-weight: 700;
  color: var(--cinnabar);
}

.fix-link {
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  font-size: 14px;
  font-weight: 500;
  color: var(--cinnabar);
}

.fix-link::after {
  content: "→";
  margin-left: 6px;
}

/* 相关内容入口 */
.related-links {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px;
  padding: 16px 0;
  border-top: 1px solid var(--line);
}

.related-links-label {
  font-family: var(--font-serif);
  font-size: 13px;
  font-weight: 700;
  color: var(--pine);
  margin-right: 4px;
}

.related-links-item {
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  padding: 0 14px;
  font-size: 14px;
  color: var(--ink);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background-color: var(--white);
}

.related-links-item:hover {
  border-color: var(--cinnabar);
  color: var(--cinnabar);
}

/* ==========================================================================
   内页模块
   ========================================================================== */

.section {
  margin-bottom: 44px;
}

.section-title {
  font-size: 26px;
  margin-bottom: 12px;
}

.section-intro {
  font-size: 15px;
  line-height: 1.8;
  color: var(--ink-soft);
  margin-bottom: 20px;
  max-width: 68ch;
}

.section-note {
  font-size: 14px;
  line-height: 1.75;
  color: var(--pine);
  margin-bottom: 16px;
  max-width: 68ch;
}

/* --- 题材目录页 --- */

.section-overview {
  padding-bottom: 36px;
  border-bottom: 1px solid var(--line);
}

.overview-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 340px);
  gap: 32px;
  align-items: start;
}

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

.overview-text p {
  font-size: 16px;
  line-height: 1.8;
  margin-bottom: 14px;
}

.overview-points {
  display: flex;
  flex-direction: column;
  gap: 8px;
  margin-top: 4px;
}

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

.overview-points li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 10px;
  width: 8px;
  height: 2px;
  background-color: var(--cinnabar);
}

.section-topic-list {
  padding-bottom: 36px;
  border-bottom: 1px solid var(--line);
}

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

.topic-rows .topic-row {
  display: grid;
  grid-template-columns: minmax(160px, 220px) minmax(0, 1fr);
  gap: 24px;
  padding: 20px 6px;
  border-bottom: 1px solid var(--line);
  transition: background-color .18s ease;
}

.topic-rows .topic-row:hover {
  background-color: var(--paper-deep);
}

.topic-rows .topic-name {
  display: flex;
  align-items: baseline;
  gap: 10px;
  min-width: 0;
}

.topic-index {
  font-family: var(--font-serif);
  font-size: 13px;
  font-weight: 700;
  color: var(--cinnabar);
  flex-shrink: 0;
}

.topic-title {
  font-size: 18px;
  line-height: 1.45;
}

.topic-detail {
  min-width: 0;
}

.topic-summary {
  font-size: 15px;
  line-height: 1.8;
  margin-bottom: 10px;
}

.topic-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 22px;
  margin-bottom: 8px;
}

.topic-meta-item {
  display: flex;
  gap: 6px;
  font-size: 13px;
  line-height: 1.7;
  color: var(--pine);
  min-width: 0;
}

.topic-meta-item dt {
  font-weight: 500;
  color: var(--ink);
  flex-shrink: 0;
}

.topic-meta-item dd {
  margin: 0;
  color: var(--ink-soft);
}

.topic-rows .topic-link {
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  padding: 0;
  font-size: 14px;
  font-weight: 500;
  color: var(--cinnabar);
  border: 0;
  background: none;
}

.topic-rows .topic-link::after {
  content: "→";
  margin-left: 6px;
}

.section-threshold {
  padding-bottom: 20px;
}

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

.threshold-item {
  display: flex;
  flex-direction: column;
  gap: 8px;
  min-width: 0;
  padding: 18px;
  background-color: var(--white);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.threshold-tag {
  font-family: var(--font-serif);
  font-size: 12px;
  font-weight: 700;
  color: var(--cinnabar);
  letter-spacing: .06em;
}

.threshold-title {
  font-size: 17px;
  line-height: 1.45;
}

.threshold-item p {
  font-size: 14px;
  line-height: 1.75;
  flex: 1 1 auto;
}

.threshold-link {
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  font-size: 14px;
  font-weight: 500;
  color: var(--cinnabar);
}

.threshold-link::after {
  content: "→";
  margin-left: 6px;
}

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

.boundary-note {
  margin-top: 20px;
  padding: 16px 18px;
  background-color: var(--paper-deep);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  font-size: 14px;
  line-height: 1.8;
  color: var(--ink-soft);
}

/* --- 阅读路径页 --- */

.conclusion-box {
  padding: 22px 24px;
  background-color: var(--white);
  border: 1px solid var(--line);
  border-left: 4px solid var(--cinnabar);
  border-radius: var(--radius);
  margin-bottom: 40px;
}

.conclusion-box h2 {
  font-size: 22px;
  margin-bottom: 8px;
}

.conclusion-intro {
  font-size: 15px;
  line-height: 1.8;
  margin-bottom: 14px;
}

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

.conclusion-item {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 6px 14px;
  padding: 10px 0;
  border-top: 1px dashed var(--line);
}

.conclusion-text {
  flex: 1 1 320px;
  min-width: 0;
  font-size: 15px;
  line-height: 1.75;
  color: var(--ink);
}

.conclusion-item .inline-link {
  flex-shrink: 0;
}

.principle-section {
  padding-bottom: 36px;
  border-bottom: 1px solid var(--line);
  margin-bottom: 40px;
}

.principle-section h2 {
  font-size: 26px;
  margin-bottom: 18px;
}

.principle-body {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 300px);
  gap: 32px;
  align-items: start;
}

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

.principle-text p {
  font-size: 16px;
  line-height: 1.85;
  margin-bottom: 14px;
}

.principle-text p:last-child {
  margin-bottom: 0;
}

.example-section {
  padding-bottom: 36px;
  border-bottom: 1px solid var(--line);
  margin-bottom: 40px;
}

.example-section h2 {
  font-size: 26px;
  margin-bottom: 12px;
}

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

.example-item {
  display: flex;
  flex-direction: column;
  gap: 8px;
  min-width: 0;
  padding: 20px 18px;
  background-color: var(--white);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.example-heading {
  font-size: 18px;
  line-height: 1.45;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--line);
}

.example-bg,
.example-method,
.example-evidence,
.example-summary {
  font-size: 14px;
  line-height: 1.75;
  color: var(--ink-soft);
}

.example-evidence {
  color: var(--pine);
}

.example-summary {
  color: var(--ink);
  font-weight: 500;
}

.mistake-section {
  padding-bottom: 12px;
}

.mistake-section h2 {
  font-size: 26px;
  margin-bottom: 18px;
}

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

.mistake-item {
  display: grid;
  grid-template-columns: minmax(150px, 200px) minmax(0, 1fr);
  gap: 20px;
  padding: 16px 4px;
  border-bottom: 1px solid var(--line);
}

.mistake-heading {
  font-size: 16px;
  line-height: 1.5;
}

.mistake-wrong {
  font-size: 14px;
  line-height: 1.75;
  color: var(--ink-soft);
  margin-bottom: 4px;
}

.mistake-fix {
  font-size: 14px;
  line-height: 1.75;
  color: var(--pine);
}

/* --- 专题档案页 --- */

.special-index {
  padding-bottom: 32px;
  border-bottom: 1px solid var(--line);
  margin-bottom: 40px;
}

.special-index .section-head {
  margin-bottom: 18px;
}

.special-index .section-head h2 {
  font-size: 26px;
}

.index-row {
  display: grid;
  grid-template-columns: minmax(170px, 230px) minmax(0, 1fr);
  gap: 24px;
  padding: 20px 6px;
  border-bottom: 1px solid var(--line);
  transition: background-color .18s ease;
}

.index-row:first-of-type {
  border-top: 1px solid var(--line);
}

.index-row:hover {
  background-color: var(--paper-deep);
}

.index-row-key {
  min-width: 0;
}

.index-num {
  display: inline-block;
  font-family: var(--font-serif);
  font-size: 13px;
  font-weight: 700;
  color: var(--cinnabar);
  margin-bottom: 4px;
}

.index-row-key h3 {
  font-size: 18px;
  line-height: 1.45;
  margin-bottom: 6px;
}

.index-tag {
  font-size: 13px;
  color: var(--pine);
}

.index-row-body {
  min-width: 0;
}

.index-summary {
  font-size: 15px;
  line-height: 1.8;
  margin-bottom: 8px;
}

.index-meta {
  font-size: 13px;
  line-height: 1.7;
  color: var(--pine);
  margin-bottom: 4px;
}

.index-link {
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  font-size: 14px;
  font-weight: 500;
  color: var(--cinnabar);
}

.index-link::after {
  content: "→";
  margin-left: 6px;
}

.media-figure {
  margin-bottom: 40px;
}

.special-compose {
  padding-bottom: 32px;
  border-bottom: 1px solid var(--line);
  margin-bottom: 36px;
}

.special-compose .section-head h2 {
  font-size: 26px;
}

.compose-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 20px;
}

.compose-item {
  min-width: 0;
  padding: 20px 18px;
  background-color: var(--white);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.compose-item h3 {
  font-size: 17px;
  margin-bottom: 8px;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--line);
}

.compose-item p {
  font-size: 14px;
  line-height: 1.8;
  margin-bottom: 6px;
}

.special-rules {
  padding-bottom: 12px;
}

.special-rules .section-head h2 {
  font-size: 26px;
}

.rules-list {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.rule-item {
  padding: 18px 20px;
  background-color: var(--paper-deep);
  border-left: 3px solid var(--pine);
  border-radius: 0 var(--radius) var(--radius) 0;
}

.rule-item h3 {
  font-size: 17px;
  margin-bottom: 6px;
}

.rule-item p {
  font-size: 14px;
  line-height: 1.8;
}

.rule-action {
  margin-top: 6px;
}

.rule-action a {
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  font-size: 14px;
  font-weight: 500;
  color: var(--cinnabar);
}

.rule-action a::after {
  content: "→";
  margin-left: 6px;
}

/* --- 术语表页 --- */

.glossary-index {
  padding-bottom: 32px;
  border-bottom: 1px solid var(--line);
  margin-bottom: 36px;
}

.glossary-index h2 {
  font-size: 26px;
  margin-bottom: 10px;
}

.index-group {
  margin-bottom: 16px;
}

.index-group:last-child {
  margin-bottom: 0;
}

.index-group-title {
  font-size: 15px;
  color: var(--pine);
  padding-bottom: 6px;
  margin-bottom: 6px;
  border-bottom: 1px solid var(--line);
}

.index-rows {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 4px 24px;
}

.index-row {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 12px;
  min-width: 0;
  padding: 6px 4px;
  border-radius: var(--radius);
  transition: background-color .18s ease;
}

.index-row:hover {
  background-color: var(--paper-deep);
}

.index-term {
  display: inline-flex;
  align-items: center;
  min-height: 32px;
  font-size: 14px;
  color: var(--ink);
  min-width: 0;
}

.index-term:hover {
  color: var(--cinnabar);
}

.index-cat {
  font-size: 12px;
  color: var(--pine);
  white-space: nowrap;
  flex-shrink: 0;
}

.term-body {
  padding-bottom: 32px;
  border-bottom: 1px solid var(--line);
  margin-bottom: 36px;
}

.term-body h2 {
  font-size: 26px;
  margin-bottom: 10px;
}

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

.term-row {
  display: grid;
  grid-template-columns: minmax(120px, 170px) minmax(0, 1fr);
  gap: 24px;
  padding: 20px 4px;
  border-bottom: 1px solid var(--line);
}

.term-row:first-of-type {
  border-top: 1px solid var(--line);
}

.term-name {
  font-size: 18px;
  line-height: 1.45;
}

.term-detail {
  min-width: 0;
}

.term-def {
  font-size: 15px;
  line-height: 1.8;
  color: var(--ink);
  margin-bottom: 6px;
}

.term-use {
  font-size: 14px;
  line-height: 1.75;
  margin-bottom: 4px;
}

.term-confuse {
  font-size: 14px;
  line-height: 1.75;
  color: var(--pine);
  margin-bottom: 4px;
}

.term-link {
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  font-size: 14px;
  font-weight: 500;
  color: var(--cinnabar);
}

.term-link::after {
  content: "→";
  margin-left: 6px;
}

.term-boundary {
  padding-bottom: 12px;
}

.term-boundary h2 {
  font-size: 26px;
  margin-bottom: 10px;
}

.confuse-list {
  display: flex;
  flex-direction: column;
  gap: 12px;
  margin-bottom: 20px;
}

.confuse-item {
  padding: 14px 18px;
  background-color: var(--white);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

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

.confuse-item dd {
  margin: 0;
  font-size: 14px;
  line-height: 1.8;
  color: var(--ink-soft);
}

.correction-note {
  padding: 18px 20px;
  background-color: var(--paper-deep);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.correction-note h3 {
  font-size: 16px;
  margin-bottom: 6px;
}

.correction-note p {
  font-size: 14px;
  line-height: 1.8;
  margin-bottom: 4px;
}

.correction-link {
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  font-size: 14px;
  font-weight: 500;
  color: var(--cinnabar);
}

.correction-link::after {
  content: "→";
  margin-left: 6px;
}

/* --- 常见问题页 --- */

.faq-intro {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 300px);
  gap: 32px;
  align-items: start;
  padding-bottom: 32px;
  border-bottom: 1px solid var(--line);
  margin-bottom: 36px;
}

.faq-intro-text {
  min-width: 0;
}

.faq-intro-text .section-title {
  margin-bottom: 10px;
}

.faq-intro-text p {
  font-size: 15px;
  line-height: 1.8;
  margin-bottom: 12px;
}

.faq-intro-list {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

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

.faq-intro-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 10px;
  width: 8px;
  height: 2px;
  background-color: var(--cinnabar);
}

.faq-group {
  margin-bottom: 32px;
  padding-bottom: 24px;
  border-bottom: 1px solid var(--line);
}

.faq-group:last-of-type {
  border-bottom: 0;
}

.faq-group .section-title {
  margin-bottom: 6px;
}

.group-desc {
  font-size: 14px;
  line-height: 1.75;
  color: var(--pine);
  margin-bottom: 14px;
}

.faq-item {
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background-color: var(--white);
  margin-bottom: 10px;
  overflow: hidden;
}

.faq-question {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  min-height: 52px;
  padding: 12px 18px;
  font-family: var(--font-serif);
  font-size: 16px;
  font-weight: 500;
  color: var(--ink);
  cursor: pointer;
  list-style: none;
}

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

.faq-question::after {
  content: "＋";
  font-size: 14px;
  color: var(--cinnabar);
  flex-shrink: 0;
}

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

.faq-item[open] .faq-question {
  color: var(--cinnabar);
  border-bottom: 1px solid var(--line);
}

.faq-answer {
  padding: 14px 18px 16px;
}

.faq-answer p {
  font-size: 14px;
  line-height: 1.85;
  margin-bottom: 8px;
}

.faq-related {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 16px;
  margin-bottom: 0;
}

.faq-related a {
  display: inline-flex;
  align-items: center;
  min-height: 40px;
  font-size: 14px;
  font-weight: 500;
  color: var(--cinnabar);
}

.faq-related a::after {
  content: "→";
  margin-left: 4px;
}

.faq-next {
  padding: 22px 24px;
  background-color: var(--paper-deep);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.faq-next .section-title {
  margin-bottom: 8px;
}

.faq-next p {
  font-size: 14px;
  line-height: 1.8;
  margin-bottom: 12px;
}

.faq-next-list {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.faq-next-list a {
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  padding: 0 14px;
  font-size: 14px;
  color: var(--ink);
  background-color: var(--white);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.faq-next-list a:hover {
  border-color: var(--cinnabar);
  color: var(--cinnabar);
}

/* --- 关于本站页 --- */

.about-position {
  padding-bottom: 32px;
  border-bottom: 1px solid var(--line);
  margin-bottom: 36px;
}

.about-position h2 {
  font-size: 26px;
  margin-bottom: 16px;
}

.position-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 300px);
  gap: 32px;
  align-items: start;
}

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

.position-text p {
  font-size: 16px;
  line-height: 1.85;
  margin-bottom: 14px;
}

.position-readers {
  min-width: 0;
  padding: 20px;
  background-color: var(--white);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.position-readers h3 {
  font-size: 17px;
  margin-bottom: 12px;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--line);
}

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

.reader-item {
  font-size: 14px;
  line-height: 1.75;
  color: var(--ink-soft);
  padding-left: 14px;
  border-left: 2px solid var(--line);
}

.reader-label {
  display: block;
  font-family: var(--font-serif);
  font-weight: 700;
  color: var(--ink);
  margin-bottom: 2px;
}

.about-principles {
  padding-bottom: 32px;
  border-bottom: 1px solid var(--line);
  margin-bottom: 36px;
}

.about-principles h2 {
  font-size: 26px;
  margin-bottom: 10px;
}

.principle-list {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 16px;
  margin-bottom: 16px;
}

.principle-item {
  min-width: 0;
  padding: 18px;
  background-color: var(--white);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.principle-item h3 {
  font-size: 16px;
  margin-bottom: 6px;
  color: var(--ink);
}

.principle-item p {
  font-size: 14px;
  line-height: 1.8;
}

.principle-note {
  padding: 14px 18px;
  background-color: var(--paper-deep);
  border-left: 3px solid var(--pine);
  border-radius: 0 var(--radius) var(--radius) 0;
}

.principle-note p {
  font-size: 14px;
  line-height: 1.8;
}

.about-dual-path {
  padding-bottom: 32px;
  border-bottom: 1px solid var(--line);
  margin-bottom: 36px;
}

.about-dual-path h2 {
  font-size: 26px;
  margin-bottom: 10px;
}

.dual-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 20px;
}

.dual-col {
  min-width: 0;
  padding: 20px;
  background-color: var(--white);
  border: 1px solid var(--line);
  border-top: 3px solid var(--cinnabar);
  border-radius: var(--radius);
}

.dual-col h3 {
  font-size: 17px;
  margin-bottom: 12px;
}

.dual-steps {
  display: flex;
  flex-direction: column;
  gap: 10px;
  counter-reset: dualstep;
}

.dual-step {
  position: relative;
  padding-left: 30px;
  font-size: 14px;
  line-height: 1.75;
  color: var(--ink-soft);
  counter-increment: dualstep;
}

.dual-step::before {
  content: counter(dualstep);
  position: absolute;
  left: 0;
  top: 2px;
  width: 20px;
  height: 20px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: var(--font-serif);
  font-size: 12px;
  font-weight: 700;
  color: var(--cinnabar);
  border: 1px solid var(--line);
  border-radius: 50%;
}

.about-correction {
  padding-bottom: 12px;
}

.about-correction h2 {
  font-size: 26px;
  margin-bottom: 10px;
}

.correction-flow {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 20px;
  margin-bottom: 20px;
}

.correction-step {
  position: relative;
  min-width: 0;
  padding: 18px 18px 18px 18px;
  background-color: var(--white);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.step-num {
  display: inline-block;
  font-family: var(--font-serif);
  font-size: 13px;
  font-weight: 700;
  color: var(--cinnabar);
  margin-bottom: 6px;
}

.correction-step h3 {
  font-size: 16px;
  margin-bottom: 6px;
}

.correction-step p {
  font-size: 14px;
  line-height: 1.75;
}

.boundary-note {
  padding: 18px 20px;
  background-color: var(--paper-deep);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.boundary-note h3 {
  font-size: 16px;
  margin-bottom: 10px;
}

/* ==========================================================================
   404 页面
   ========================================================================== */

.error-main {
  flex: 1 0 auto;
  width: 100%;
  max-width: 760px;
  margin: 0 auto;
  padding: 56px 24px 64px;
}

.error-panel {
  padding: 32px 0 36px;
  border-bottom: 1px solid var(--line);
  margin-bottom: 32px;
}

.error-code {
  font-family: var(--font-serif);
  font-size: 64px;
  font-weight: 700;
  line-height: 1;
  color: var(--cinnabar);
  margin-bottom: 12px;
}

.error-title {
  font-size: 32px;
  margin-bottom: 12px;
}

.error-desc {
  font-size: 16px;
  line-height: 1.8;
  margin-bottom: 22px;
  max-width: 52ch;
}

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

.error-guide-title {
  font-size: 22px;
  margin-bottom: 14px;
}

.error-link-list {
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.error-link-list a {
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  font-size: 15px;
  color: var(--ink);
  border-bottom: 1px solid var(--line);
}

.error-link-list a:hover {
  color: var(--cinnabar);
}

.error-link-list a::after {
  content: "→";
  margin-left: 8px;
  color: var(--cinnabar);
}

/* ==========================================================================
   页脚
   ========================================================================== */

.site-footer {
  flex-shrink: 0;
  background-color: var(--paper-deep);
  border-top: 1px solid var(--line);
  margin-top: auto;
}

.footer-top {
  max-width: var(--shell-max);
  margin: 0 auto;
  padding: 32px 24px 20px;
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 8px 20px;
  border-bottom: 1px solid var(--line);
}

.footer-brand {
  font-family: var(--font-serif);
  font-size: 20px;
  font-weight: 700;
  color: var(--ink);
}

.footer-desc {
  font-size: 14px;
  line-height: 1.7;
  color: var(--pine);
}

.footer-cols {
  max-width: var(--shell-max);
  margin: 0 auto;
  padding: 26px 24px;
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 24px;
}

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

.footer-heading {
  font-family: var(--font-serif);
  font-size: 14px;
  font-weight: 700;
  color: var(--ink);
  margin-bottom: 10px;
  padding-bottom: 6px;
  border-bottom: 1px solid var(--line);
}

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

.footer-list a {
  display: inline-flex;
  align-items: center;
  min-height: 32px;
  font-size: 14px;
  color: var(--ink-soft);
}

.footer-list a:hover {
  color: var(--cinnabar);
}

.footer-bottom {
  max-width: var(--shell-max);
  margin: 0 auto;
  padding: 14px 24px 22px;
  border-top: 1px solid var(--line);
}

.copyright {
  font-size: 13px;
  line-height: 1.7;
  color: var(--pine);
}

/* ==========================================================================
   响应式：1120px 与 760px 断点
   ========================================================================== */

@media (max-width: 1120px) {
  :root {
    --sidebar-w: 204px;
    --gap: 28px;
  }

  .header-inner {
    gap: 18px;
  }

  .brand-slogan {
    display: none;
  }

  .nav-link {
    padding: 0 9px;
    font-size: 13px;
  }

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

  .hero-text h1 {
    font-size: 34px;
  }

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

  .special-body,
  .overview-grid,
  .principle-body,
  .faq-intro,
  .position-grid {
    grid-template-columns: minmax(0, 1fr);
    gap: 24px;
  }

  .special-figure {
    position: static;
  }

  .special-figure img,
  .overview-figure img,
  .principle-figure img,
  .faq-intro-figure img,
  .about-figure img {
    aspect-ratio: 16 / 9;
  }

  .topic-rows .topic-row,
  .index-row,
  .term-row,
  .mistake-item {
    grid-template-columns: minmax(140px, 190px) minmax(0, 1fr);
    gap: 18px;
  }

  .track-list,
  .glossary-groups,
  .threshold-grid,
  .example-list,
  .correction-flow,
  .fix-steps {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

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

@media (max-width: 760px) {
  :root {
    --gap: 0px;
  }

  body.site-body {
    font-size: 16px;
  }

  /* 页头：品牌 + 汉堡按钮 */
  .header-inner {
    height: 60px;
    padding: 0 16px;
    gap: 12px;
    flex-wrap: nowrap;
  }

  .brand {
    min-width: 0;
    flex: 1 1 auto;
  }

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

  .menu-toggle {
    display: inline-flex;
    flex-shrink: 0;
  }

  /* 主导航收起，仅在 .nav-list.is-open 时展开 */
  .primary-nav {
    order: 3;
    flex-basis: 100%;
    margin-left: 0;
  }

  .nav-list {
    display: none;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    padding: 6px 0 10px;
    border-top: 1px solid var(--line);
  }

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

  .nav-link {
    min-height: 44px;
    padding: 0 4px;
    font-size: 15px;
    border-bottom: 1px solid var(--line);
  }

  .nav-link.is-current {
    border-bottom-color: var(--cinnabar);
  }

  /* 布局：主内容在前，侧栏作为抽屉覆盖层 */
  .layout-shell,
  .page-layout,
  .layout-shell.sidebar-left,
  .page-layout.sidebar-left {
    display: block;
    padding: 20px 16px 44px;
  }

  .side-nav,
  .site-sidebar,
  .site-drawer {
    position: fixed;
    top: 0;
    left: 0;
    bottom: 0;
    width: min(86vw, 320px);
    max-height: 100vh;
    height: 100vh;
    z-index: 120;
    padding: 18px 16px 28px;
    border-radius: 0;
    border: 0;
    border-right: 1px solid var(--line);
    overflow-y: auto;
    transform: translateX(-102%);
    transition: transform .24s ease;
    visibility: hidden;
  }

  .side-nav.is-open,
  .site-sidebar.is-open,
  .site-drawer.is-open {
    transform: translateX(0);
    visibility: visible;
  }

  .drawer-close {
    display: inline-flex;
    align-items: center;
    justify-content: center;
  }

  .side-nav-head,
  .sidebar-head {
    padding-bottom: 14px;
  }

  .side-link,
  .nav-group-list a,
  .group-list a {
    min-height: 44px;
    font-size: 15px;
  }

  .site-main,
  .inner-main {
    max-width: 100%;
  }

  /* 面包屑与标题区 */
  .breadcrumb {
    padding-bottom: 12px;
    font-size: 12px;
  }

  .page-header {
    padding-bottom: 14px;
    margin-bottom: 20px;
  }

  .page-title {
    font-size: 30px;
    line-height: 1.32;
  }

  .page-title-block,
  .page-head {
    margin-bottom: 22px;
  }

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

  .section-title,
  .section-head h2,
  .principle-section h2,
  .example-section h2,
  .mistake-section h2,
  .special-index .section-head h2,
  .special-compose .section-head h2,
  .special-rules .section-head h2,
  .glossary-index h2,
  .term-body h2,
  .term-boundary h2,
  .about-position h2,
  .about-principles h2,
  .about-dual-path h2,
  .about-correction h2 {
    font-size: 22px;
  }

  /* 首页首屏 */
  .hero-desk {
    padding-bottom: 28px;
    margin-bottom: 32px;
    gap: 22px;
  }

  .hero-text h1 {
    font-size: 30px;
    line-height: 1.32;
    margin-bottom: 12px;
  }

  .hero-kicker {
    margin-bottom: 8px;
  }

  .hero-lead {
    font-size: 15px;
    line-height: 1.8;
    margin-bottom: 18px;
  }

  .hero-actions {
    gap: 10px;
    margin-bottom: 20px;
  }

  .btn {
    flex: 1 1 140px;
    min-height: 46px;
    padding: 0 16px;
    font-size: 15px;
  }

  .hero-index {
    padding: 16px 14px;
  }

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

  .hero-index .topic-row {
    grid-template-columns: 28px minmax(0, 1fr) auto;
    grid-template-areas:
      "no name link"
      "no scope link";
    row-gap: 2px;
    padding: 10px 2px;
  }

  .hero-index .topic-no {
    grid-area: no;
    align-self: start;
    padding-top: 2px;
  }

  .hero-index .topic-name {
    grid-area: name;
  }

  .hero-index .topic-scope {
    grid-area: scope;
    font-size: 12.5px;
  }

  .hero-index .topic-link {
    grid-area: link;
    align-self: center;
    min-height: 36px;
  }

  /* 首页模块间距 */
  .special-index,
  .path-track,
  .glossary-quick {
    padding-bottom: 28px;
    margin-bottom: 32px;
  }

  .section-head {
    margin-bottom: 16px;
  }

  .section-desc {
    font-size: 14px;
  }

  .special-item {
    grid-template-columns: 32px minmax(0, 1fr);
    column-gap: 10px;
    padding: 14px 2px;
  }

  .special-name {
    font-size: 17px;
  }

  .track-list,
  .glossary-groups,
  .threshold-grid,
  .example-list,
  .correction-flow,
  .fix-steps,
  .dual-grid,
  .principle-list,
  .compose-grid {
    grid-template-columns: minmax(0, 1fr);
    gap: 14px;
  }

  .track-step,
  .glossary-group,
  .threshold-item,
  .example-item,
  .correction-step,
  .dual-col,
  .principle-item,
  .compose-item {
    padding: 16px 14px;
  }

  .boundary-body {
    grid-template-columns: minmax(0, 1fr);
    gap: 14px;
    margin-bottom: 20px;
  }

  .boundary {
    padding-bottom: 24px;
    margin-bottom: 24px;
  }

  .fix-flow {
    padding: 16px 14px;
  }

  .fix-step {
    padding-left: 30px;
  }

  .related-links {
    gap: 8px;
    padding: 14px 0;
  }

  .related-links-item {
    flex: 1 1 132px;
    justify-content: center;
    padding: 0 10px;
    font-size: 13px;
  }

  /* 内页列表与摘要：单列堆叠 */
  .section {
    margin-bottom: 32px;
  }

  .section-overview,
  .section-topic-list,
  .principle-section,
  .example-section,
  .special-index,
  .special-compose,
  .glossary-index,
  .term-body,
  .about-position,
  .about-principles,
  .about-dual-path {
    padding-bottom: 26px;
    margin-bottom: 30px;
  }

  .faq-intro {
    padding-bottom: 24px;
    margin-bottom: 28px;
  }

  .topic-rows .topic-row,
  .index-row,
  .term-row,
  .mistake-item {
    grid-template-columns: minmax(0, 1fr);
    gap: 8px;
    padding: 16px 2px;
  }

  .topic-rows .topic-name {
    gap: 8px;
  }

  .topic-title,
  .index-row-key h3,
  .term-name,
  .mistake-heading {
    font-size: 17px;
  }

  .topic-summary,
  .index-summary,
  .term-def {
    font-size: 14.5px;
  }

  .topic-meta {
    gap: 4px 16px;
  }

  .conclusion-box {
    padding: 18px 16px;
    margin-bottom: 30px;
  }

  .conclusion-box h2 {
    font-size: 20px;
  }

  .conclusion-item {
    flex-direction: column;
    align-items: flex-start;
    gap: 2px;
  }

  .conclusion-text {
    flex: 1 1 auto;
  }

  .principle-text p,
  .position-text p,
  .overview-text p {
    font-size: 15px;
    line-height: 1.8;
  }

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

  .index-row {
    padding: 4px 2px;
  }

  .index-term {
    min-height: 36px;
    font-size: 14.5px;
  }

  .confuse-item,
  .correction-note,
  .boundary-note,
  .principle-note,
  .faq-next {
    padding: 14px 14px;
  }

  .faq-question {
    padding: 12px 14px;
    font-size: 15px;
    min-height: 48px;
  }

  .faq-answer {
    padding: 12px 14px 14px;
  }

  .faq-next-list a {
    flex: 1 1 132px;
    justify-content: center;
    padding: 0 10px;
    font-size: 13px;
  }

  .position-readers {
    padding: 16px 14px;
  }

  /* 404 */
  .error-main {
    padding: 36px 16px 48px;
  }

  .error-code {
    font-size: 48px;
  }

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

  .error-desc {
    font-size: 15px;
  }

  .error-actions .btn {
    flex: 1 1 140px;
  }

  /* 页脚 */
  .footer-top {
    padding: 24px 16px 16px;
    flex-direction: column;
    align-items: flex-start;
    gap: 6px;
  }

  .footer-cols {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 18px 16px;
    padding: 20px 16px;
  }

  .footer-list a {
    min-height: 40px;
  }

  .footer-bottom {
    padding: 12px 16px 20px;
  }
}

@media (max-width: 380px) {
  .hero-index .topic-row {
    grid-template-columns: 24px minmax(0, 1fr);
    grid-template-areas:
      "no name"
      "no scope"
      "no link";
  }

  .hero-index .topic-link {
    justify-self: start;
    margin-top: 2px;
  }

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

/* 程序验收反馈：移动端防溢出 */
@media (max-width: 768px) {
  .site-main,
  .site-main * {
    min-width: 0;
    max-width: 100%;
  }

  .site-main :is(h1, h2, h3, h4, p, a, span) {
    overflow-wrap: anywhere;
  }
}