:root {
  --bg-page: #f7faf9;
  --bg-surface: #ffffff;
  --bg-tint: #eaf4f1;
  --text-main: #22312e;
  --text-muted: #5b6f6a;
  --brand: #1f7a6b;
  --brand-deep: #155a4f;
  --accent: #3f8fb5;
  --line: #d8e4e0;
  --line-strong: #b9cdc7;
  --radius-sm: 4px;
  --radius-md: 8px;
  --shadow-soft: 0 1px 2px rgba(34, 49, 46, 0.06), 0 6px 18px rgba(34, 49, 46, 0.05);
  --container: 1120px;
  --gap: 24px;
  --focus-ring: 0 0 0 3px rgba(63, 143, 181, 0.45);
}

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

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

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

body.site-body {
  margin: 0;
  padding: 0;
  background-color: var(--bg-page);
  color: var(--text-main);
  font-family: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Source Han Sans SC", "Noto Sans CJK SC", system-ui, -apple-system, "Segoe UI", sans-serif;
  font-size: 16px;
  line-height: 1.75;
  font-weight: 400;
  letter-spacing: 0;
  -webkit-font-smoothing: antialiased;
}

h1,
h2,
h3,
h4 {
  margin: 0;
  color: var(--text-main);
  font-weight: 700;
  line-height: 1.4;
}

p {
  margin: 0;
}

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

a {
  color: var(--brand);
  text-decoration: none;
  transition: color 0.18s ease, border-color 0.18s ease, background-color 0.18s ease;
}

a:hover {
  color: var(--brand-deep);
}

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

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

figure {
  margin: 0;
}

table {
  border-collapse: collapse;
  width: 100%;
}

.skip-link {
  position: absolute;
  left: -9999px;
  top: 0;
  z-index: 200;
  padding: 10px 16px;
  background-color: var(--brand);
  color: #ffffff;
  border-radius: 0 0 var(--radius-md) 0;
}

.skip-link:focus {
  left: 0;
}

/* ============================================================
   layout · 全站骨架
   ============================================================ */

.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background-color: rgba(247, 250, 249, 0.96);
  border-bottom: 1px solid var(--line);
  backdrop-filter: saturate(140%) blur(6px);
}

.header-inner {
  max-width: var(--container);
  margin: 0 auto;
  padding: 14px 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  transition: padding 0.2s ease;
}

.site-brand {
  display: flex;
  align-items: center;
  gap: 12px;
  flex: 0 0 auto;
  color: var(--text-main);
}

.site-brand:hover {
  color: var(--text-main);
}

.brand-mark {
  width: 34px;
  height: 34px;
  flex: 0 0 34px;
  border-radius: var(--radius-md);
  background-color: var(--brand);
  position: relative;
}

.brand-mark::after {
  content: "";
  position: absolute;
  left: 50%;
  top: 50%;
  width: 12px;
  height: 12px;
  transform: translate(-50%, -50%) rotate(45deg);
  border: 2px solid #ffffff;
  border-radius: 2px;
}

.brand-text {
  display: flex;
  flex-direction: column;
  line-height: 1.25;
}

.brand-name {
  font-size: 17px;
  font-weight: 700;
  color: var(--text-main);
}

.brand-slogan {
  font-size: 12px;
  color: var(--text-muted);
}

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

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

.nav-list li {
  display: block;
}

.nav-list a {
  display: block;
  padding: 10px 14px;
  font-size: 15px;
  color: var(--text-main);
  border-radius: var(--radius-sm);
  border-bottom: 2px solid transparent;
  white-space: nowrap;
}

.nav-list a:hover {
  color: var(--brand);
  background-color: var(--bg-tint);
}

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

.nav-toggle {
  display: none;
  width: 44px;
  height: 44px;
  padding: 0;
  border: 1px solid var(--line-strong);
  border-radius: var(--radius-md);
  background-color: var(--bg-surface);
  cursor: pointer;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 5px;
}

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

.site-main {
  display: block;
}

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

.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  font-size: 14px;
  color: var(--text-muted);
  margin-bottom: 18px;
}

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

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

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

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

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

.page-title {
  font-size: 30px;
  font-weight: 700;
  line-height: 1.35;
  color: var(--text-main);
  margin-bottom: 12px;
}

.page-description {
  max-width: 46em;
  font-size: 16px;
  color: var(--text-muted);
  line-height: 1.8;
}

.site-footer {
  margin-top: 48px;
  background-color: var(--bg-surface);
  border-top: 1px solid var(--line);
}

.footer-inner {
  max-width: var(--container);
  margin: 0 auto;
  padding: 40px 24px 28px;
  display: grid;
  grid-template-columns: minmax(240px, 1.4fr) minmax(200px, 1fr) minmax(200px, 1fr);
  gap: 32px 40px;
}

.footer-brand {
  font-size: 16px;
  font-weight: 700;
  color: var(--text-main);
  margin-bottom: 10px;
}

.footer-desc {
  font-size: 14px;
  color: var(--text-muted);
  line-height: 1.8;
  max-width: 34em;
}

.footer-nav-title {
  font-size: 15px;
  font-weight: 700;
  color: var(--text-main);
  margin-bottom: 12px;
}

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

.footer-nav-list a {
  display: inline-block;
  font-size: 14px;
  color: var(--text-muted);
  padding: 2px 0;
}

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

.footer-meta {
  display: flex;
  flex-direction: column;
  gap: 8px;
  font-size: 14px;
  color: var(--text-muted);
}

.footer-current {
  color: var(--text-main);
  font-weight: 600;
}

.back-to-top {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 8px 14px;
  border: 1px solid var(--line-strong);
  border-radius: var(--radius-md);
  color: var(--text-main);
  font-size: 14px;
  background-color: var(--bg-page);
}

.back-to-top:hover {
  color: var(--brand);
  border-color: var(--brand);
  background-color: var(--bg-tint);
}

/* ============================================================
   components · 通用
   ============================================================ */

.section {
  margin-bottom: 48px;
}

.section-head {
  margin-bottom: 22px;
}

.section-title {
  font-size: 22px;
  font-weight: 700;
  color: var(--text-main);
  margin-bottom: 10px;
}

.section-desc,
.section-intro,
.section-lead {
  max-width: 46em;
  font-size: 15px;
  color: var(--text-muted);
  line-height: 1.8;
}

.section-foot {
  margin-top: 18px;
  font-size: 15px;
}

.link-inline {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  color: var(--brand);
  font-weight: 600;
  border-bottom: 1px solid rgba(31, 122, 107, 0.35);
  padding-bottom: 2px;
}

.link-inline:hover {
  border-bottom-color: var(--brand);
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 44px;
  padding: 10px 22px;
  border-radius: var(--radius-md);
  font-size: 15px;
  font-weight: 600;
  border: 1px solid transparent;
  cursor: pointer;
}

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

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

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

.btn-ghost:hover {
  color: var(--brand-deep);
  border-color: var(--brand);
  background-color: var(--bg-tint);
}

.table-wrap {
  width: 100%;
  overflow-x: auto;
  background-color: var(--bg-surface);
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
}

.table-caption {
  caption-side: top;
  text-align: left;
  padding: 14px 18px 0;
  font-size: 14px;
  color: var(--text-muted);
}

.field-table,
.compare-table {
  min-width: 520px;
  font-size: 15px;
}

.field-table th,
.field-table td,
.compare-table th,
.compare-table td {
  padding: 13px 18px;
  text-align: left;
  vertical-align: top;
  border-bottom: 1px solid var(--line);
  line-height: 1.7;
}

.field-table thead th,
.compare-table thead th {
  background-color: var(--bg-tint);
  color: var(--text-main);
  font-weight: 700;
  font-size: 14px;
  white-space: nowrap;
}

.field-table tbody th,
.compare-table tbody th {
  color: var(--brand);
  font-weight: 600;
  white-space: nowrap;
  background-color: #fbfdfc;
}

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

.section-note {
  margin-top: 16px;
  font-size: 14px;
  color: var(--text-muted);
  display: flex;
  flex-wrap: wrap;
  gap: 8px 18px;
}

.section-note a {
  color: var(--brand);
  font-weight: 600;
}

.step-list {
  display: grid;
  gap: 14px;
  counter-reset: step;
}

.step-item {
  display: grid;
  grid-template-columns: 40px minmax(0, 1fr);
  gap: 14px;
  align-items: start;
  padding: 16px 18px;
  background-color: var(--bg-surface);
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
}

.step-index {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 32px;
  height: 32px;
  border-radius: var(--radius-md);
  background-color: var(--bg-tint);
  color: var(--brand);
  font-weight: 700;
  font-size: 15px;
}

.step-title {
  font-size: 16px;
  font-weight: 700;
  margin-bottom: 6px;
}

.step-text {
  font-size: 15px;
  color: var(--text-muted);
  line-height: 1.8;
}

.step-text a {
  color: var(--brand);
  font-weight: 600;
}

.step-item p {
  font-size: 15px;
  color: var(--text-muted);
  line-height: 1.8;
}

.step-check {
  border-color: var(--brand);
  background-color: var(--bg-tint);
}

.step-check .step-index {
  background-color: var(--brand);
  color: #ffffff;
}

.faq-list {
  display: grid;
  gap: 12px;
}

.faq-item {
  background-color: var(--bg-surface);
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  padding: 0;
  overflow: hidden;
}

.faq-question {
  cursor: pointer;
  list-style: none;
  padding: 16px 46px 16px 18px;
  font-size: 16px;
  font-weight: 600;
  color: var(--text-main);
  position: relative;
}

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

.faq-question::after {
  content: "";
  position: absolute;
  right: 20px;
  top: 50%;
  width: 9px;
  height: 9px;
  border-right: 2px solid var(--brand);
  border-bottom: 2px solid var(--brand);
  transform: translateY(-70%) rotate(45deg);
  transition: transform 0.2s ease;
}

.faq-item[open] .faq-question::after {
  transform: translateY(-30%) rotate(-135deg);
}

.faq-item[open] .faq-question {
  color: var(--brand);
}

.faq-answer {
  padding: 0 18px 18px;
  font-size: 15px;
  color: var(--text-muted);
  line-height: 1.8;
  border-top: 1px solid var(--line);
  padding-top: 14px;
}

.faq-answer p {
  margin: 0;
}

.faq-answer p + p {
  margin-top: 10px;
}

/* ============================================================
   pages · 首页
   ============================================================ */

.home-main {
  display: block;
}

.hero-section {
  max-width: var(--container);
  margin: 0 auto;
  padding: 40px 24px 8px;
}

.hero-layout {
  display: grid;
  grid-template-columns: minmax(0, 1.05fr) minmax(0, 0.95fr);
  gap: 36px;
  align-items: center;
}

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

.hero-eyebrow {
  display: inline-block;
  font-size: 13px;
  font-weight: 600;
  color: var(--brand);
  background-color: var(--bg-tint);
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
  padding: 4px 12px;
  margin-bottom: 16px;
}

.hero-title {
  font-size: 34px;
  font-weight: 700;
  line-height: 1.35;
  color: var(--text-main);
  margin-bottom: 16px;
}

.hero-lead {
  font-size: 16px;
  color: var(--text-muted);
  line-height: 1.85;
  max-width: 34em;
  margin-bottom: 20px;
}

.hero-points {
  display: grid;
  gap: 10px;
  margin-bottom: 26px;
}

.hero-points li {
  position: relative;
  padding-left: 22px;
  font-size: 15px;
  color: var(--text-main);
  line-height: 1.75;
}

.hero-points li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 11px;
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background-color: var(--accent);
}

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

.hero-media {
  position: relative;
  border-radius: var(--radius-md);
  overflow: hidden;
  border: 1px solid var(--line);
  background-color: var(--bg-surface);
  box-shadow: var(--shadow-soft);
}

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

.hero-caption {
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px;
  padding: 12px 16px;
  background-color: rgba(21, 90, 79, 0.82);
  color: #ffffff;
  font-size: 13px;
}

.meta-label {
  font-weight: 600;
  color: #d9f0ea;
}

.meta-value {
  color: #ffffff;
}

.hero-entries {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 16px;
  margin-top: 32px;
}

.entry-card {
  display: flex;
  flex-direction: column;
  gap: 6px;
  padding: 18px;
  background-color: var(--bg-surface);
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  color: var(--text-main);
  min-height: 44px;
}

.entry-card:hover {
  border-color: var(--brand);
  background-color: var(--bg-tint);
  color: var(--text-main);
}

.entry-index {
  font-size: 13px;
  font-weight: 700;
  color: var(--accent);
}

.entry-title {
  font-size: 17px;
  font-weight: 700;
  color: var(--text-main);
}

.entry-desc {
  font-size: 14px;
  color: var(--text-muted);
  line-height: 1.7;
}

.channel-overview,
.topic-overview,
.field-overview,
.notice-overview,
.boundary-section {
  max-width: var(--container);
  margin: 0 auto 48px;
  padding: 0 24px;
}

.channel-groups {
  display: grid;
  gap: 12px;
}

.channel-row {
  display: grid;
  grid-template-columns: minmax(140px, 200px) minmax(0, 1fr);
  gap: 18px;
  align-items: baseline;
  padding: 16px 20px;
  background-color: var(--bg-surface);
  border: 1px solid var(--line);
  border-left: 3px solid var(--brand);
  border-radius: var(--radius-md);
  color: var(--text-main);
}

.channel-row:hover {
  border-color: var(--brand);
  background-color: var(--bg-tint);
  color: var(--text-main);
}

.channel-name {
  font-size: 16px;
  font-weight: 700;
  color: var(--brand);
}

.channel-scope {
  font-size: 15px;
  color: var(--text-muted);
  line-height: 1.75;
}

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

.topic-item {
  display: flex;
  flex-direction: column;
  background-color: var(--bg-surface);
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  overflow: hidden;
}

.topic-media {
  border-bottom: 1px solid var(--line);
}

.topic-media img {
  width: 100%;
  aspect-ratio: 16 / 10;
  object-fit: cover;
}

.topic-body {
  padding: 18px;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

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

.topic-scope {
  font-size: 13px;
  color: var(--brand);
  background-color: var(--bg-tint);
  border-radius: var(--radius-sm);
  padding: 3px 10px;
  align-self: flex-start;
}

.topic-note {
  font-size: 14px;
  color: var(--text-muted);
  line-height: 1.75;
}

.notice-list {
  display: grid;
  gap: 14px;
}

.notice-item {
  display: grid;
  grid-template-columns: 40px minmax(0, 1fr);
  gap: 14px;
  align-items: start;
  padding: 16px 18px;
  background-color: var(--bg-surface);
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
}

.notice-index {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 32px;
  height: 32px;
  border-radius: var(--radius-md);
  background-color: var(--bg-tint);
  color: var(--brand);
  font-weight: 700;
  font-size: 15px;
}

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

.notice-name {
  font-size: 16px;
  font-weight: 700;
  margin-bottom: 6px;
}

.notice-body p {
  font-size: 15px;
  color: var(--text-muted);
  line-height: 1.8;
}

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

.boundary-item {
  padding: 20px;
  background-color: var(--bg-surface);
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
}

.boundary-name {
  font-size: 16px;
  font-weight: 700;
  color: var(--brand);
  margin-bottom: 10px;
}

.boundary-item p {
  font-size: 15px;
  color: var(--text-muted);
  line-height: 1.8;
}

/* ============================================================
   pages · 题材频道
   ============================================================ */

.page-layout {
  display: block;
}

.section-overview,
.section-channels,
.section-pitfalls,
.section-terms,
.section-related {
  margin-bottom: 44px;
}

.channel-overview-list {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 14px;
  margin-top: 18px;
}

.channel-overview-item {
  min-width: 0;
}

.channel-overview-link {
  display: flex;
  flex-direction: column;
  gap: 6px;
  height: 100%;
  padding: 16px 18px;
  background-color: var(--bg-surface);
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  color: var(--text-main);
  min-height: 44px;
}

.channel-overview-link:hover {
  border-color: var(--brand);
  background-color: var(--bg-tint);
  color: var(--text-main);
}

.overview-name {
  font-size: 16px;
  font-weight: 700;
  color: var(--brand);
}

.overview-range {
  font-size: 14px;
  color: var(--text-muted);
  line-height: 1.75;
}

.section-channels .channel-block {
  display: grid;
  grid-template-columns: minmax(0, 320px) minmax(0, 1fr);
  gap: 26px;
  align-items: start;
  padding: 22px 0;
  border-top: 1px solid var(--line);
}

.section-channels .channel-block:last-child {
  border-bottom: 1px solid var(--line);
}

.channel-figure {
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  overflow: hidden;
  background-color: var(--bg-surface);
}

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

.channel-figure-caption {
  padding: 10px 14px;
  font-size: 13px;
  color: var(--text-muted);
  background-color: var(--bg-page);
  border-top: 1px solid var(--line);
}

.channel-body {
  min-width: 0;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.channel-body .channel-name {
  font-size: 19px;
  color: var(--text-main);
}

.channel-definition {
  font-size: 15px;
  font-weight: 600;
  color: var(--brand);
  line-height: 1.75;
}

.channel-detail {
  font-size: 15px;
  color: var(--text-main);
  line-height: 1.85;
}

.channel-example,
.channel-term {
  font-size: 14px;
  color: var(--text-muted);
  line-height: 1.8;
  padding: 10px 14px;
  background-color: var(--bg-tint);
  border-radius: var(--radius-md);
}

.pitfall-list {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 16px;
  margin-top: 18px;
}

.pitfall-item {
  padding: 18px;
  background-color: var(--bg-surface);
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  min-width: 0;
}

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

.pitfall-fix {
  font-size: 15px;
  color: var(--text-muted);
  line-height: 1.8;
}

.term-list {
  margin: 18px 0 0;
  display: grid;
  grid-template-columns: minmax(140px, 200px) minmax(0, 1fr);
  gap: 0;
  background-color: var(--bg-surface);
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  overflow: hidden;
}

.term-name {
  padding: 14px 18px;
  font-size: 15px;
  font-weight: 700;
  color: var(--brand);
  background-color: var(--bg-tint);
  border-bottom: 1px solid var(--line);
  border-right: 1px solid var(--line);
}

.term-usage {
  margin: 0;
  padding: 14px 18px;
  font-size: 15px;
  color: var(--text-muted);
  line-height: 1.8;
  border-bottom: 1px solid var(--line);
}

.term-list .term-name:last-of-type,
.term-list .term-usage:last-of-type {
  border-bottom: 0;
}

.section-related {
  padding: 20px;
  background-color: var(--bg-surface);
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
}

.related-title {
  font-size: 17px;
  font-weight: 700;
  margin-bottom: 12px;
}

.related-list {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 10px;
}

.related-list a {
  display: block;
  padding: 12px 14px;
  min-height: 44px;
  background-color: var(--bg-page);
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  color: var(--brand);
  font-weight: 600;
  font-size: 15px;
}

.related-list a:hover {
  border-color: var(--brand);
  background-color: var(--bg-tint);
}

/* ============================================================
   pages · 专题片单
   ============================================================ */

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

.content-section > h2 {
  font-size: 22px;
  font-weight: 700;
  margin-bottom: 12px;
}

.organize-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 20px;
  margin-top: 18px;
}

.organize-block {
  padding: 20px;
  background-color: var(--bg-surface);
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  min-width: 0;
}

.organize-title {
  font-size: 17px;
  font-weight: 700;
  color: var(--brand);
  margin-bottom: 10px;
}

.organize-text {
  font-size: 15px;
  color: var(--text-muted);
  line-height: 1.85;
}

.organize-text + .organize-text {
  margin-top: 10px;
}

.topic-vs-channel .section-lead {
  margin-bottom: 18px;
}

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

.compare-column {
  padding: 20px;
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  background-color: var(--bg-surface);
  min-width: 0;
}

.compare-topic {
  border-top: 3px solid var(--brand);
}

.compare-channel {
  border-top: 3px solid var(--accent);
}

.compare-title {
  font-size: 17px;
  font-weight: 700;
  margin-bottom: 12px;
}

.compare-list {
  display: grid;
  gap: 10px;
  margin-bottom: 14px;
}

.compare-item {
  position: relative;
  padding-left: 20px;
  font-size: 15px;
  color: var(--text-main);
  line-height: 1.8;
}

.compare-item::before {
  content: "";
  position: absolute;
  left: 0;
  top: 11px;
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background-color: var(--accent);
}

.compare-note {
  font-size: 14px;
  color: var(--text-muted);
  line-height: 1.8;
  padding-top: 12px;
  border-top: 1px solid var(--line);
}

.compare-note a {
  color: var(--brand);
  font-weight: 600;
}

.topic-list-section .section-lead {
  margin-bottom: 18px;
}

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

.topic-list .topic-item {
  display: grid;
  grid-template-columns: minmax(160px, 220px) minmax(0, 1fr);
  gap: 18px;
  align-items: start;
  padding: 18px 20px;
  background-color: var(--bg-surface);
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
}

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

.topic-list .topic-scope {
  grid-column: 2;
  font-size: 13px;
  color: var(--brand);
  background-color: var(--bg-tint);
  border-radius: var(--radius-sm);
  padding: 3px 10px;
  align-self: start;
  justify-self: start;
}

.topic-list .topic-desc {
  grid-column: 2;
  font-size: 15px;
  color: var(--text-muted);
  line-height: 1.8;
}

.topic-figure {
  margin-top: 24px;
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  overflow: hidden;
  background-color: var(--bg-surface);
}

.topic-figure img {
  width: 100%;
  aspect-ratio: 21 / 9;
  object-fit: cover;
}

.topic-figure-caption {
  padding: 10px 16px;
  font-size: 13px;
  color: var(--text-muted);
  border-top: 1px solid var(--line);
  background-color: var(--bg-page);
}

.topic-boundary .section-lead {
  margin-bottom: 18px;
}

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

.boundary-list .boundary-item {
  position: relative;
  padding: 16px 18px 16px 40px;
  font-size: 15px;
  color: var(--text-main);
  line-height: 1.8;
  background-color: var(--bg-surface);
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  min-width: 0;
}

.boundary-list .boundary-item::before {
  content: "×";
  position: absolute;
  left: 16px;
  top: 15px;
  color: var(--accent);
  font-weight: 700;
}

.boundary-note {
  margin-top: 18px;
  font-size: 15px;
  color: var(--text-muted);
  line-height: 1.8;
}

.boundary-note a {
  color: var(--brand);
  font-weight: 600;
}

/* ============================================================
   pages · 剧集目录
   ============================================================ */

.catalog-media,
.catalog-fields,
.catalog-compare,
.catalog-steps,
.catalog-faq {
  margin-bottom: 44px;
}

.catalog-media .section-title,
.catalog-fields .section-title,
.catalog-compare .section-title,
.catalog-steps .section-title,
.catalog-faq .section-title {
  margin-bottom: 14px;
}

.media-figure {
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  overflow: hidden;
  background-color: var(--bg-surface);
}

.media-figure img {
  width: 100%;
  aspect-ratio: 21 / 9;
  object-fit: cover;
}

.media-figure figcaption {
  padding: 10px 16px;
  font-size: 13px;
  color: var(--text-muted);
  border-top: 1px solid var(--line);
  background-color: var(--bg-page);
}

.catalog-fields .section-lead,
.catalog-compare .section-lead {
  margin-bottom: 16px;
}

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

.catalog-steps .step-list {
  margin-top: 16px;
}

/* ============================================================
   pages · 观看指南
   ============================================================ */

.guide-visual,
.guide-prep,
.guide-order,
.guide-faq,
.guide-check {
  margin-bottom: 44px;
}

.guide-visual .section-title,
.guide-prep .section-title,
.guide-order .section-title,
.guide-faq .section-title,
.guide-check .section-title {
  margin-bottom: 14px;
}

.guide-figure {
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  overflow: hidden;
  background-color: var(--bg-surface);
}

.guide-figure img {
  width: 100%;
  aspect-ratio: 21 / 9;
  object-fit: cover;
}

.guide-figure figcaption {
  padding: 10px 16px;
  font-size: 13px;
  color: var(--text-muted);
  border-top: 1px solid var(--line);
  background-color: var(--bg-page);
}

.guide-prep .section-intro,
.guide-order .section-intro,
.guide-faq .section-intro,
.guide-check .section-intro {
  margin-bottom: 16px;
}

.prep-list {
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
}

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

.order-list .step-item {
  grid-template-columns: 40px minmax(0, 1fr);
}

.check-list {
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
}

.check-list .step-item {
  grid-template-columns: minmax(0, 1fr);
  gap: 0;
  border-left: 3px solid var(--brand);
}

/* ============================================================
   pages · 404
   ============================================================ */

.error-main {
  max-width: var(--container);
  margin: 0 auto;
  padding: 56px 24px 64px;
}

.error-panel {
  max-width: 640px;
  padding: 32px;
  background-color: var(--bg-surface);
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-soft);
}

.error-code {
  font-size: 40px;
  font-weight: 700;
  color: var(--brand);
  line-height: 1;
  margin-bottom: 14px;
}

.error-panel h1 {
  font-size: 26px;
  font-weight: 700;
  margin-bottom: 12px;
}

.error-lead {
  font-size: 16px;
  color: var(--text-muted);
  line-height: 1.85;
  margin-bottom: 20px;
}

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

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

.error-routes h2 {
  font-size: 20px;
  font-weight: 700;
  margin-bottom: 16px;
}

.error-route-list {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 12px;
}

.error-route-list a {
  display: block;
  padding: 14px 16px;
  min-height: 44px;
  background-color: var(--bg-surface);
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  color: var(--brand);
  font-weight: 600;
  font-size: 15px;
}

.error-route-list a:hover {
  border-color: var(--brand);
  background-color: var(--bg-tint);
}

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

@media (max-width: 960px) {
  .header-inner {
    padding: 12px 20px;
  }

  .nav-toggle {
    display: flex;
  }

  .site-nav {
    position: relative;
    flex: 0 0 auto;
  }

  .nav-list {
    position: absolute;
    top: calc(100% + 12px);
    right: 0;
    min-width: 220px;
    flex-direction: column;
    align-items: stretch;
    gap: 2px;
    padding: 10px;
    background-color: var(--bg-surface);
    border: 1px solid var(--line);
    border-radius: var(--radius-md);
    box-shadow: var(--shadow-soft);
    display: none;
  }

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

  .nav-list a {
    padding: 12px 14px;
    min-height: 44px;
    display: flex;
    align-items: center;
    border-bottom: 0;
    border-left: 2px solid transparent;
  }

  .nav-list a.is-current {
    border-left-color: var(--brand);
    background-color: var(--bg-tint);
  }

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

  .hero-title {
    font-size: 28px;
  }

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

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

  .section-channels .channel-block {
    grid-template-columns: minmax(0, 260px) minmax(0, 1fr);
    gap: 22px;
  }

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

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

@media (max-width: 640px) {
  body.site-body {
    font-size: 15px;
  }

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

  .brand-slogan {
    display: none;
  }

  .inner-main {
    padding: 20px 16px 44px;
  }

  .hero-section {
    padding: 28px 16px 4px;
  }

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

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

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

  .hero-actions .btn {
    width: 100%;
  }

  .channel-overview,
  .topic-overview,
  .field-overview,
  .notice-overview,
  .boundary-section {
    padding: 0 16px;
    margin-bottom: 36px;
  }

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

  .section-title,
  .content-section > h2,
  .error-routes h2 {
    font-size: 20px;
  }

  .channel-row {
    grid-template-columns: minmax(0, 1fr);
    gap: 6px;
    padding: 14px 16px;
  }

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

  .boundary-grid,
  .organize-grid,
  .compare-columns {
    grid-template-columns: minmax(0, 1fr);
  }

  .channel-overview-list {
    grid-template-columns: minmax(0, 1fr);
  }

  .section-channels .channel-block {
    grid-template-columns: minmax(0, 1fr);
    gap: 16px;
    padding: 18px 0;
  }

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

  .term-name {
    border-right: 0;
    border-bottom: 0;
    padding-bottom: 4px;
  }

  .term-usage {
    border-bottom: 1px solid var(--line);
  }

  .topic-list .topic-item {
    grid-template-columns: minmax(0, 1fr);
    gap: 8px;
    padding: 16px;
  }

  .topic-list .topic-scope,
  .topic-list .topic-desc {
    grid-column: 1;
  }

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

  .step-index {
    width: 28px;
    height: 28px;
    font-size: 14px;
  }

  .prep-list .step-item,
  .check-list .step-item,
  .order-list .step-item {
    grid-template-columns: minmax(0, 1fr);
  }

  .prep-list .step-index,
  .check-list .step-index {
    margin-bottom: 8px;
  }

  .faq-question {
    font-size: 15px;
    padding: 14px 42px 14px 16px;
  }

  .footer-inner {
    grid-template-columns: minmax(0, 1fr);
    padding: 32px 16px 24px;
    gap: 26px;
  }

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

  .error-panel {
    padding: 24px 18px;
  }

  .error-code {
    font-size: 32px;
  }

  .error-panel h1 {
    font-size: 22px;
  }

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

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

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