/* ==========================================================================
   91制品 · 全站样式
   分组：base / layout / components / pages / responsive
   ========================================================================== */

/* --------------------------------------------------------------------------
   base
   -------------------------------------------------------------------------- */

:root {
  --paper: #FAF8F3;
  --surface: #FFFFFF;
  --ink: #1B1F1D;
  --ink-soft: #59635D;
  --green: #1F4B3F;
  --green-deep: #163830;
  --green-tint: #E8EDE7;
  --indigo: #35586B;
  --indigo-tint: #E7EDF0;
  --brick: #BF6A32;
  --brick-tint: #F4E9DF;
  --line: #E1DDD1;
  --line-strong: #CFC9B9;
  --notice-bg: #F2EEE2;
  --radius-sm: 4px;
  --radius-md: 6px;
  --shell: 1120px;
  --gutter: 24px;
  --font-sans: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", system-ui, sans-serif;
  --font-mono: "SFMono-Regular", "Menlo", "Consolas", "Liberation Mono", monospace;
}

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

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

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

h1,
h2,
h3,
h4 {
  margin: 0 0 0.5em;
  font-weight: 600;
  line-height: 1.35;
  color: var(--green);
}

h1 {
  font-size: clamp(26px, 4vw, 38px);
  letter-spacing: 0.01em;
}

h2 {
  font-size: 22px;
}

h3 {
  font-size: 18px;
}

p {
  margin: 0 0 1em;
}

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

li {
  margin-bottom: 0.4em;
}

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

a {
  color: var(--green);
  text-decoration: underline;
  text-underline-offset: 3px;
  text-decoration-thickness: 1px;
}

a:hover {
  color: var(--green-deep);
  text-decoration-thickness: 2px;
}

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

figure {
  margin: 0;
}

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

time {
  font-variant-numeric: tabular-nums;
}

.skip-link {
  position: absolute;
  left: 16px;
  top: -60px;
  z-index: 60;
  padding: 10px 16px;
  background: var(--green);
  color: #fff;
  text-decoration: none;
  border-radius: var(--radius-sm);
  transition: top 0.16s ease;
}

.skip-link:focus {
  top: 12px;
  color: #fff;
}

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

/* --------------------------------------------------------------------------
   layout · 全站骨架
   -------------------------------------------------------------------------- */

.site-header {
  background: var(--green);
  border-bottom: 3px solid var(--brick);
}

.header-inner {
  max-width: var(--shell);
  margin: 0 auto;
  padding: 0 var(--gutter);
  min-height: 64px;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px 24px;
}

.brand {
  display: flex;
  flex-direction: column;
  justify-content: center;
  gap: 1px;
  padding: 10px 0;
  text-decoration: none;
  color: #fff;
}

.brand:hover {
  color: #fff;
  text-decoration: none;
}

.brand-name {
  font-size: 20px;
  font-weight: 600;
  line-height: 1.2;
}

.brand-slogan {
  font-size: 12px;
  line-height: 1.4;
  color: #C7D6CD;
}

.nav-toggle {
  display: none;
  margin-left: auto;
  width: 44px;
  height: 44px;
  padding: 0;
  border: 1px solid rgba(255, 255, 255, 0.35);
  border-radius: var(--radius-sm);
  background: transparent;
  cursor: pointer;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 5px;
}

.nav-toggle-bar {
  display: block;
  width: 20px;
  height: 2px;
  background: #fff;
  border-radius: 1px;
  transition: transform 0.16s ease, opacity 0.16s ease;
}

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

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

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

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

.primary-nav ul {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 2px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.primary-nav li {
  margin: 0;
}

.primary-nav a {
  display: block;
  padding: 8px 12px;
  font-size: 15px;
  line-height: 1.4;
  color: #E6EDE9;
  text-decoration: none;
  border-radius: var(--radius-sm);
  border-bottom: 2px solid transparent;
}

.primary-nav a:hover {
  color: #fff;
  background: rgba(255, 255, 255, 0.1);
  text-decoration: none;
}

.primary-nav a.is-current {
  color: #fff;
  font-weight: 600;
  border-bottom-color: var(--brick);
}

.site-main {
  display: block;
}

.inner-main {
  max-width: var(--shell);
  margin: 0 auto;
  padding: 0 var(--gutter) 64px;
}

.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 6px;
  padding: 20px 0 0;
  font-size: 13px;
  line-height: 1.6;
  color: var(--ink-soft);
}

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

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

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

.page-header {
  padding: 10px 0 0;
}

.page-title {
  margin: 0;
  font-size: clamp(26px, 4vw, 38px);
  font-weight: 600;
  line-height: 1.3;
  color: var(--green);
}

.page-hero,
.page-head {
  padding: 12px 0 24px;
  border-bottom: 1px solid var(--line);
  margin-bottom: 32px;
}

.section-label {
  margin: 0 0 6px;
  font-size: 13px;
  font-weight: 500;
  letter-spacing: 0.08em;
  color: var(--indigo);
}

.page-summary {
  margin: 0 0 18px;
  max-width: 68ch;
  font-size: 16px;
  line-height: 1.75;
  color: var(--ink-soft);
}

.meta-bar {
  display: flex;
  flex-wrap: wrap;
  gap: 0;
  margin: 0;
  padding: 12px 0;
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}

.meta-item {
  flex: 1 1 200px;
  min-width: 160px;
  padding: 0 20px 0 0;
  margin: 0;
}

.meta-item + .meta-item {
  padding-left: 20px;
  border-left: 1px solid var(--line);
}

.meta-item dt {
  font-size: 12px;
  font-weight: 500;
  letter-spacing: 0.08em;
  color: var(--indigo);
}

.meta-item dd {
  margin: 2px 0 0;
  font-size: 14px;
  line-height: 1.6;
  color: var(--ink);
  font-variant-numeric: tabular-nums;
}

/* 右侧栏布局：主内容在前，aside 在后 */
.page-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 320px;
  gap: 48px;
  align-items: start;
}

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

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

/* --------------------------------------------------------------------------
   components · 通用模块
   -------------------------------------------------------------------------- */

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

.section-head h2 {
  margin-bottom: 6px;
  padding-bottom: 10px;
  border-bottom: 2px solid var(--green);
  display: inline-block;
}

.section-sub {
  margin: 0;
  max-width: 68ch;
  font-size: 15px;
  line-height: 1.7;
  color: var(--ink-soft);
}

.section-intro {
  margin: 0 0 20px;
  max-width: 68ch;
  font-size: 15px;
  line-height: 1.7;
  color: var(--ink-soft);
}

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

.content-block > h2,
.content-section > h2 {
  margin-bottom: 12px;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--line);
}

.content-block > p,
.content-section > p {
  max-width: 68ch;
}

/* 图片容器 */
.content-figure,
.section-figure,
.guide-figure,
.task-figure,
.topic-figure,
.hero-figure {
  margin: 0 0 20px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  overflow: hidden;
}

.content-figure img,
.section-figure img,
.guide-figure img,
.task-figure img,
.topic-figure img,
.hero-figure img {
  width: 100%;
  height: auto;
  object-fit: cover;
}

.content-figure figcaption,
.section-figure figcaption,
.guide-figure figcaption,
.task-figure figcaption,
.topic-figure figcaption,
.hero-figure figcaption {
  padding: 8px 14px 10px;
  margin: 0;
  border-top: 1px solid var(--line);
  background: var(--paper);
}

/* 提示框：核对 / 注意 */
.notice,
.notice-box {
  padding: 14px 18px;
  margin: 0 0 20px;
  background: var(--notice-bg);
  border-radius: var(--radius-sm);
  border-left: 4px solid var(--indigo);
}

.notice-title {
  margin: 0 0 4px;
  font-size: 15px;
  font-weight: 600;
  color: var(--indigo);
}

.notice p,
.notice-box p {
  margin: 0;
  font-size: 14px;
  line-height: 1.7;
  color: var(--ink);
}

.notice-caution,
.notice-warn {
  border-left-color: var(--brick);
}

.notice-caution .notice-title,
.notice-warn .notice-title,
.notice-box.notice-warn h3 {
  color: var(--brick);
}

.notice-check {
  border-left-color: var(--indigo);
}

.notice-box h3 {
  margin: 0 0 4px;
  font-size: 15px;
  font-weight: 600;
  color: var(--indigo);
}

/* 编号列表 */
.numbered-list {
  counter-reset: numlist;
  list-style: none;
  padding-left: 0;
  margin: 0 0 20px;
}

.numbered-list > li {
  position: relative;
  padding: 0 0 16px 44px;
  margin-bottom: 16px;
  border-bottom: 1px solid var(--line);
}

.numbered-list > li:last-child {
  border-bottom: 0;
  padding-bottom: 0;
  margin-bottom: 0;
}

.numbered-list > li::before {
  counter-increment: numlist;
  content: counter(numlist, decimal-leading-zero);
  position: absolute;
  left: 0;
  top: 2px;
  width: 32px;
  font-family: var(--font-mono);
  font-size: 14px;
  font-weight: 600;
  line-height: 1.6;
  color: var(--brick);
  font-variant-numeric: tabular-nums;
}

.numbered-list h3 {
  margin: 0 0 4px;
  font-size: 16px;
}

.numbered-list p {
  margin: 0;
  font-size: 15px;
  line-height: 1.7;
  color: var(--ink-soft);
}

/* 对照两列 */
.compare-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 24px;
  margin: 0 0 20px;
}

.compare-col {
  min-width: 0;
  padding: 16px 18px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
}

.compare-col h3,
.compare-title {
  margin: 0 0 10px;
  font-size: 16px;
  color: var(--indigo);
}

.compare-list {
  margin: 0;
  padding-left: 1.1em;
}

.compare-list li {
  margin-bottom: 8px;
  font-size: 15px;
  line-height: 1.7;
}

.compare-list li:last-child {
  margin-bottom: 0;
}

/* 侧栏 */
.side-block,
.sidebar-block {
  margin-bottom: 28px;
  padding: 16px 18px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
}

.side-nav,
.anchor-nav,
.related-nav {
  padding: 16px 18px;
  margin-bottom: 28px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
}

.side-nav-title,
.side-block-title,
.side-title,
.sidebar-title {
  margin: 0 0 10px;
  padding-bottom: 8px;
  font-size: 14px;
  font-weight: 600;
  letter-spacing: 0.06em;
  color: var(--indigo);
  border-bottom: 1px solid var(--line);
}

.side-nav ul,
.side-block ul,
.anchor-nav ul,
.related-nav ul,
.side-link-list,
.sidebar-link-list,
.related-list {
  margin: 0;
  padding: 0;
  list-style: none;
}

.side-nav li,
.side-block li,
.anchor-nav li,
.related-nav li,
.side-link-list li,
.sidebar-link-list li,
.related-list li {
  margin: 0 0 2px;
}

.side-nav a,
.side-block a,
.anchor-nav a,
.related-nav a,
.side-link-list a,
.sidebar-link-list a,
.related-list a {
  display: block;
  padding: 7px 8px;
  font-size: 14px;
  line-height: 1.5;
  color: var(--ink);
  text-decoration: none;
  border-left: 2px solid transparent;
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
}

.side-nav a:hover,
.side-block a:hover,
.anchor-nav a:hover,
.related-nav a:hover,
.side-link-list a:hover,
.sidebar-link-list a:hover,
.related-list a:hover {
  background: var(--green-tint);
  color: var(--green-deep);
  border-left-color: var(--green);
  text-decoration: none;
}

/* 页脚 */
.site-footer {
  background: var(--green-deep);
  color: #D6E0DA;
  margin-top: 24px;
}

.footer-inner {
  max-width: var(--shell);
  margin: 0 auto;
  padding: 40px var(--gutter) 24px;
}

.footer-brand-row {
  display: flex;
  flex-wrap: wrap;
  align-items: flex-start;
  justify-content: space-between;
  gap: 16px 32px;
  padding-bottom: 24px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.15);
}

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

.footer-brand-name {
  display: block;
  font-size: 20px;
  font-weight: 600;
  color: #fff;
}

.footer-slogan {
  margin: 4px 0 0;
  font-size: 14px;
  color: #A9BDB2;
}

.footer-scope {
  margin: 0;
  max-width: 46ch;
  font-size: 14px;
  line-height: 1.7;
  color: #A9BDB2;
}

.footer-cols {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 24px;
  padding: 28px 0;
  border-bottom: 1px solid rgba(255, 255, 255, 0.15);
}

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

.footer-col-title {
  margin: 0 0 10px;
  font-size: 14px;
  font-weight: 600;
  letter-spacing: 0.06em;
  color: #fff;
}

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

.footer-col li {
  margin: 0 0 6px;
}

.footer-col a {
  font-size: 14px;
  line-height: 1.6;
  color: #C7D6CD;
  text-decoration: none;
}

.footer-col a:hover {
  color: #fff;
  text-decoration: underline;
}

.footer-version {
  padding: 16px 0;
  border-bottom: 1px solid rgba(255, 255, 255, 0.15);
}

.footer-version p {
  margin: 0;
  font-size: 13px;
  line-height: 1.7;
  color: #A9BDB2;
  font-variant-numeric: tabular-nums;
}

.footer-bottom {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 12px 24px;
  padding-top: 18px;
}

.footer-nav {
  display: flex;
  flex-wrap: wrap;
  gap: 4px 16px;
}

.footer-nav a {
  font-size: 13px;
  line-height: 1.6;
  color: #C7D6CD;
  text-decoration: none;
}

.footer-nav a:hover {
  color: #fff;
  text-decoration: underline;
}

.footer-copy {
  margin: 0;
  font-size: 13px;
  color: #8FA598;
}

.back-top {
  margin-left: auto;
  padding: 6px 12px;
  font-size: 13px;
  color: #C7D6CD;
  text-decoration: none;
  border: 1px solid rgba(255, 255, 255, 0.25);
  border-radius: var(--radius-sm);
}

.back-top:hover {
  color: #fff;
  border-color: rgba(255, 255, 255, 0.55);
  text-decoration: none;
}

/* --------------------------------------------------------------------------
   pages · 首页
   -------------------------------------------------------------------------- */

.home-main {
  max-width: var(--shell);
  margin: 0 auto;
  padding: 0 var(--gutter) 64px;
}

.home-main > section {
  padding: 44px 0;
  border-bottom: 1px solid var(--line);
}

.home-main > section:last-child {
  border-bottom: 0;
  padding-bottom: 0;
}

/* 场景选择首屏 */
.hero {
  display: grid;
  grid-template-columns: 5fr 7fr;
  gap: 40px;
  align-items: start;
  padding-top: 40px !important;
}

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

.hero-eyebrow {
  margin: 0 0 8px;
  font-size: 13px;
  font-weight: 500;
  letter-spacing: 0.08em;
  color: var(--brick);
}

.hero-lead h1 {
  margin: 0 0 10px;
}

.hero-slogan {
  margin: 0 0 12px;
  font-size: 18px;
  font-weight: 500;
  line-height: 1.5;
  color: var(--indigo);
}

.hero-desc {
  margin: 0 0 20px;
  font-size: 15px;
  line-height: 1.75;
  color: var(--ink-soft);
}

.hero-figure {
  margin-bottom: 0;
}

.hero-scenes {
  min-width: 0;
  padding: 20px 22px 8px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
}

.scenes-title {
  margin: 0 0 4px;
  font-size: 18px;
}

.scenes-desc {
  margin: 0 0 16px;
  font-size: 14px;
  line-height: 1.7;
  color: var(--ink-soft);
}

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

.scene-card {
  display: grid;
  grid-template-columns: 40px minmax(0, 1fr);
  gap: 14px;
  align-items: start;
  margin: 0 0 10px;
  padding: 14px 16px;
  background: var(--paper);
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
  transition: border-color 0.16s ease, background-color 0.16s ease;
}

.scene-card:hover,
.scene-card:focus-within {
  border-color: var(--green);
  background: var(--green-tint);
}

.scene-num {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 32px;
  font-family: var(--font-mono);
  font-size: 14px;
  font-weight: 600;
  color: var(--brick);
  background: var(--brick-tint);
  border-radius: var(--radius-sm);
  font-variant-numeric: tabular-nums;
}

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

.scene-name {
  margin: 0 0 2px;
  font-size: 16px;
  color: var(--green);
}

.scene-text {
  margin: 0 0 6px;
  font-size: 14px;
  line-height: 1.65;
  color: var(--ink-soft);
}

.scene-link {
  display: inline-block;
  padding: 2px 0;
  font-size: 14px;
  font-weight: 500;
  color: var(--indigo);
}

.scene-link::after {
  content: " →";
}

/* 任务分组总览 */
.task-columns {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 0;
  border-top: 1px solid var(--line);
}

.task-col {
  min-width: 0;
  padding: 24px 24px 4px;
  border-left: 1px solid var(--line);
}

.task-col:first-child {
  border-left: 0;
  padding-left: 0;
}

.task-col:last-child {
  padding-right: 0;
}

.task-name {
  margin: 0 0 6px;
  font-size: 18px;
}

.task-goal {
  margin: 0 0 12px;
  font-size: 14px;
  line-height: 1.7;
  color: var(--ink-soft);
}

.task-links {
  margin: 0 0 16px;
  padding: 0;
  list-style: none;
}

.task-links li {
  margin: 0 0 6px;
}

.task-links a {
  display: inline-block;
  padding: 3px 0;
  font-size: 14px;
  font-weight: 500;
  color: var(--indigo);
}

.task-links a::before {
  content: "· ";
  color: var(--brick);
}

.task-figure {
  margin-bottom: 0;
}

/* 频道速览带 */
.strip-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin: 0 0 14px;
  padding: 0;
  list-style: none;
}

.strip-tags li {
  margin: 0;
}

.tag {
  display: inline-block;
  padding: 8px 16px;
  font-size: 15px;
  line-height: 1.4;
  color: var(--green);
  background: var(--surface);
  border: 1px solid var(--line-strong);
  border-radius: var(--radius-sm);
  text-decoration: none;
  transition: background-color 0.16s ease, border-color 0.16s ease, color 0.16s ease;
}

.tag:hover,
.tag:focus-visible {
  color: var(--green-deep);
  background: var(--green-tint);
  border-color: var(--green);
  text-decoration: none;
}

.strip-note {
  margin: 0;
  max-width: 68ch;
  font-size: 14px;
  line-height: 1.7;
  color: var(--ink-soft);
}

/* 本期专题片单 */
.topic-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 320px;
  gap: 40px;
  align-items: start;
}

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

.topic-list {
  margin: 0 0 16px;
  padding: 0;
  list-style: none;
  border-top: 1px solid var(--line);
}

.topic-item {
  display: grid;
  grid-template-columns: 44px minmax(0, 1fr);
  gap: 14px;
  align-items: start;
  margin: 0;
  padding: 14px 0;
  border-bottom: 1px solid var(--line);
}

.topic-num {
  font-family: var(--font-mono);
  font-size: 15px;
  font-weight: 600;
  line-height: 1.7;
  color: var(--brick);
  text-align: right;
  font-variant-numeric: tabular-nums;
}

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

.topic-name {
  margin: 0 0 2px;
  font-size: 16px;
  color: var(--green);
}

.topic-scope {
  margin: 0;
  font-size: 14px;
  line-height: 1.7;
  color: var(--ink-soft);
}

.topic-more {
  margin: 0;
  font-size: 14px;
}

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

.topic-aside .notice {
  margin-bottom: 18px;
}

.topic-figure {
  margin-bottom: 0;
}

/* 观看前三条提示 */
.tips-list {
  margin: 0;
  padding: 0;
  list-style: none;
}

.tip-item {
  display: grid;
  grid-template-columns: 48px minmax(0, 1fr);
  gap: 16px;
  align-items: start;
  margin: 0;
  padding: 16px 0;
  border-bottom: 1px solid var(--line);
}

.tip-item:first-child {
  border-top: 1px solid var(--line);
}

.tip-num {
  font-family: var(--font-mono);
  font-size: 20px;
  font-weight: 600;
  line-height: 1.4;
  color: var(--brick);
  font-variant-numeric: tabular-nums;
}

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

.tip-name {
  margin: 0 0 4px;
  font-size: 16px;
}

.tip-body p {
  margin: 0;
  font-size: 15px;
  line-height: 1.7;
  color: var(--ink-soft);
}

/* 常见去向 */
.path-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 16px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.path-card {
  min-width: 0;
  margin: 0;
  padding: 18px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  display: flex;
  flex-direction: column;
}

.path-name {
  margin: 0 0 6px;
  font-size: 16px;
}

.path-text {
  margin: 0 0 12px;
  font-size: 14px;
  line-height: 1.65;
  color: var(--ink-soft);
}

.path-link {
  margin-top: auto;
  font-size: 14px;
  font-weight: 500;
  color: var(--indigo);
}

.path-link::after {
  content: " →";
}

/* --------------------------------------------------------------------------
   pages · 频道分类
   -------------------------------------------------------------------------- */

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

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

.channel-group > h3 {
  margin: 0 0 6px;
  font-size: 19px;
}

.group-desc {
  margin: 0 0 14px;
  font-size: 14px;
  line-height: 1.7;
  color: var(--ink-soft);
}

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

.channel-row {
  margin: 0;
  padding: 14px 0;
  border-top: 1px solid var(--line);
}

.channel-name {
  display: block;
  margin: 0 0 4px;
  font-size: 16px;
  font-weight: 600;
  color: var(--green);
}

.channel-scope {
  margin: 0 0 4px;
  font-size: 15px;
  line-height: 1.7;
}

.channel-fit {
  margin: 0;
  font-size: 14px;
  line-height: 1.7;
  color: var(--ink-soft);
}

.info-list {
  margin: 0;
  border-top: 1px solid var(--line);
}

.info-row {
  display: grid;
  grid-template-columns: 160px minmax(0, 1fr);
  gap: 20px;
  padding: 12px 0;
  border-bottom: 1px solid var(--line);
}

.info-row dt {
  font-weight: 600;
  color: var(--indigo);
}

.info-row dd {
  margin: 0;
  min-width: 0;
  font-size: 15px;
  line-height: 1.7;
  color: var(--ink-soft);
}

/* --------------------------------------------------------------------------
   pages · 专题片单
   -------------------------------------------------------------------------- */

.principle-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 16px;
  margin: 0 0 20px;
  padding: 0;
  list-style: none;
}

.principle-item {
  min-width: 0;
  margin: 0;
  padding: 16px 18px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
}

.principle-num {
  display: block;
  margin-bottom: 6px;
  font-family: var(--font-mono);
  font-size: 14px;
  font-weight: 600;
  color: var(--brick);
  font-variant-numeric: tabular-nums;
}

.principle-item h3 {
  margin: 0 0 4px;
  font-size: 16px;
}

.principle-item p {
  margin: 0;
  font-size: 14px;
  line-height: 1.7;
  color: var(--ink-soft);
}

.topic-row {
  display: grid;
  grid-template-columns: 44px minmax(0, 1fr);
  gap: 14px;
  align-items: start;
  margin: 0;
  padding: 16px 0;
  border-bottom: 1px solid var(--line);
}

.topic-list > .topic-row:first-child {
  border-top: 1px solid var(--line);
}

.topic-index {
  font-family: var(--font-mono);
  font-size: 15px;
  font-weight: 600;
  line-height: 1.7;
  color: var(--brick);
  text-align: right;
  font-variant-numeric: tabular-nums;
}

.topic-row .topic-body h3 {
  margin: 0 0 4px;
  font-size: 17px;
}

.topic-meta {
  margin: 0 0 4px;
  font-size: 13px;
  color: var(--indigo);
  font-variant-numeric: tabular-nums;
}

.topic-row .topic-body p {
  margin: 0 0 4px;
  font-size: 15px;
  line-height: 1.7;
  color: var(--ink-soft);
}

.topic-row .topic-body a {
  font-size: 14px;
  font-weight: 500;
  color: var(--indigo);
}

.struct-list {
  margin: 0;
  border-top: 1px solid var(--line);
}

.struct-row {
  display: grid;
  grid-template-columns: 140px minmax(0, 1fr);
  gap: 20px;
  padding: 12px 0;
  border-bottom: 1px solid var(--line);
}

.struct-row dt {
  font-weight: 600;
  color: var(--indigo);
}

.struct-row dd {
  margin: 0;
  min-width: 0;
  font-size: 15px;
  line-height: 1.7;
  color: var(--ink-soft);
}

.revision-list {
  margin: 0;
  padding: 0;
  list-style: none;
  border-top: 1px solid var(--line);
}

.revision-row {
  display: grid;
  grid-template-columns: 120px minmax(0, 1fr);
  gap: 16px;
  margin: 0;
  padding: 10px 0;
  border-bottom: 1px solid var(--line);
  font-size: 14px;
  line-height: 1.7;
}

.revision-date {
  font-family: var(--font-mono);
  font-weight: 600;
  color: var(--indigo);
  font-variant-numeric: tabular-nums;
}

.revision-scope {
  min-width: 0;
  color: var(--ink-soft);
}

/* --------------------------------------------------------------------------
   pages · 观看指南
   -------------------------------------------------------------------------- */

.guide-path,
.prep-list,
.interrupt-guide,
.next-step,
.revision {
  margin-bottom: 44px;
}

.guide-path > h2,
.prep-list > h2,
.interrupt-guide > h2,
.next-step > h2,
.revision > h2 {
  margin-bottom: 10px;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--line);
}

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

.step-item {
  min-width: 0;
  margin: 0;
  padding: 16px 18px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-top: 3px solid var(--green);
  border-radius: var(--radius-md);
}

.step-num {
  display: block;
  margin-bottom: 6px;
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 600;
  color: var(--brick);
  font-variant-numeric: tabular-nums;
}

.step-title,
.step-name {
  margin: 0 0 6px;
  font-size: 16px;
}

.step-desc {
  margin: 0 0 8px;
  font-size: 14px;
  line-height: 1.7;
  color: var(--ink-soft);
}

.step-check {
  margin: 0;
  padding-top: 8px;
  border-top: 1px dashed var(--line-strong);
  font-size: 13px;
  line-height: 1.6;
  color: var(--indigo);
}

.step-mark {
  margin: 8px 0 0;
  padding-top: 8px;
  border-top: 1px dashed var(--line-strong);
  font-size: 13px;
  line-height: 1.6;
  color: var(--indigo);
}

.check-list {
  margin: 0;
  padding: 0;
  list-style: none;
  border-top: 1px solid var(--line);
}

.check-item {
  display: grid;
  grid-template-columns: 180px minmax(0, 1fr);
  gap: 20px;
  align-items: baseline;
  margin: 0;
  padding: 12px 0;
  border-bottom: 1px solid var(--line);
}

.check-name {
  font-weight: 600;
  color: var(--green);
}

.check-rule,
.check-desc {
  min-width: 0;
  margin: 0;
  font-size: 15px;
  line-height: 1.7;
  color: var(--ink-soft);
}

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

.entry-block {
  min-width: 0;
  padding: 18px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  display: flex;
  flex-direction: column;
}

.entry-name {
  margin: 0 0 6px;
  font-size: 16px;
}

.entry-desc {
  margin: 0 0 12px;
  font-size: 14px;
  line-height: 1.65;
  color: var(--ink-soft);
}

.entry-link {
  margin-top: auto;
  font-size: 14px;
  font-weight: 500;
  color: var(--indigo);
}

.entry-link::after {
  content: " →";
}

.revision .revision-list {
  border-top: 1px solid var(--line);
}

.revision-item {
  display: grid;
  grid-template-columns: 120px minmax(0, 1fr) 200px;
  gap: 16px;
  margin: 0;
  padding: 12px 0;
  border-bottom: 1px solid var(--line);
  font-size: 14px;
  line-height: 1.7;
}

.revision-item p {
  margin: 0;
  min-width: 0;
  color: var(--ink-soft);
}

.revision-impact {
  color: var(--indigo);
}

.toc-nav,
.related-links {
  margin: 0 0 20px;
  padding: 14px 18px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
}

.toc-title {
  margin: 0 0 8px;
  font-size: 14px;
  font-weight: 600;
  letter-spacing: 0.06em;
  color: var(--indigo);
}

.toc-nav ul {
  display: flex;
  flex-wrap: wrap;
  gap: 4px 18px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.toc-nav li {
  margin: 0;
}

.toc-nav a {
  display: inline-block;
  padding: 4px 0;
  font-size: 14px;
  color: var(--ink);
}

.related-links {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px 18px;
}

.related-links-label {
  font-size: 14px;
  font-weight: 600;
  letter-spacing: 0.06em;
  color: var(--indigo);
}

.related-links-item {
  font-size: 14px;
  padding: 4px 0;
}

/* --------------------------------------------------------------------------
   pages · 入口核验
   -------------------------------------------------------------------------- */

.container {
  max-width: var(--shell);
  margin: 0 auto;
  padding: 0 var(--gutter);
}

.page-title-section {
  padding: 20px 0 24px;
  border-bottom: 1px solid var(--line);
  margin-bottom: 32px;
}

.page-title-section .page-summary {
  margin: 0 0 16px;
}

.layout-shell {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 320px;
  gap: 48px;
  align-items: start;
}

.layout-shell .content-main {
  min-width: 0;
}

.layout-shell .content-sidebar {
  min-width: 0;
}

.content-main > .page-header {
  padding: 0 0 12px;
}

.content-main > .breadcrumb {
  padding: 0 0 12px;
}

.check-counter {
  display: inline-block;
  margin: 0 0 12px;
  padding: 4px 12px;
  font-family: var(--font-mono);
  font-size: 14px;
  line-height: 1.6;
  color: var(--indigo);
  background: var(--indigo-tint);
  border-radius: var(--radius-sm);
  font-variant-numeric: tabular-nums;
}

.check-list .check-item {
  grid-template-columns: 44px minmax(0, 1fr);
  align-items: start;
  gap: 14px;
}

.check-item .list-index {
  font-family: var(--font-mono);
  font-size: 15px;
  font-weight: 600;
  line-height: 1.7;
  color: var(--brick);
  text-align: right;
  font-variant-numeric: tabular-nums;
}

.check-item .list-body {
  min-width: 0;
}

.check-item .list-body h3 {
  margin: 0 0 4px;
  font-size: 16px;
}

.check-item .list-body p {
  margin: 0 0 4px;
  font-size: 15px;
  line-height: 1.7;
  color: var(--ink-soft);
}

.check-item .list-body p:last-child {
  margin-bottom: 0;
}

.path-code {
  display: inline-block;
  padding: 1px 6px;
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--green-deep);
  background: var(--green-tint);
  border-radius: var(--radius-sm);
}

.def-list {
  margin: 0;
  border-top: 1px solid var(--line);
}

.def-row {
  display: grid;
  grid-template-columns: 150px minmax(0, 1fr);
  gap: 20px;
  padding: 12px 0;
  border-bottom: 1px solid var(--line);
}

.def-row dt {
  font-weight: 600;
  color: var(--indigo);
}

.def-row dd {
  margin: 0;
  min-width: 0;
  font-size: 15px;
  line-height: 1.7;
  color: var(--ink-soft);
}

.revision-section .revision-list {
  margin-top: 4px;
}

/* --------------------------------------------------------------------------
   pages · 问题反馈
   -------------------------------------------------------------------------- */

.problem-table {
  width: 100%;
  margin: 0 0 20px;
  border-collapse: collapse;
  font-size: 15px;
  line-height: 1.7;
  background: var(--surface);
  border: 1px solid var(--line);
}

.problem-table thead th {
  padding: 10px 14px;
  text-align: left;
  font-size: 14px;
  font-weight: 600;
  color: var(--green-deep);
  background: var(--green-tint);
  border-bottom: 1px solid var(--line-strong);
}

.problem-table tbody th,
.problem-table tbody td {
  padding: 12px 14px;
  text-align: left;
  vertical-align: top;
  border-bottom: 1px solid var(--line);
}

.problem-table tbody th {
  width: 30%;
  font-weight: 600;
  color: var(--indigo);
}

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

.problem-table tbody td {
  color: var(--ink-soft);
}

.problem-table a {
  color: var(--indigo);
}

#info-checklist .check-list {
  margin-bottom: 8px;
}

#info-checklist .check-item {
  grid-template-columns: 180px minmax(0, 1fr);
  align-items: baseline;
}

.faq-list {
  margin: 0;
  border-top: 1px solid var(--line);
}

.faq-item {
  border-bottom: 1px solid var(--line);
}

.faq-item summary {
  position: relative;
  padding: 14px 36px 14px 0;
  font-size: 16px;
  font-weight: 600;
  line-height: 1.6;
  color: var(--green);
  cursor: pointer;
  list-style: none;
}

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

.faq-item summary::after {
  content: "+";
  position: absolute;
  right: 6px;
  top: 50%;
  transform: translateY(-50%);
  width: 22px;
  text-align: center;
  font-family: var(--font-mono);
  font-size: 18px;
  line-height: 1;
  color: var(--brick);
}

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

.faq-item summary:hover {
  color: var(--green-deep);
}

.faq-body {
  padding: 0 0 16px;
}

.faq-body p {
  margin: 0 0 8px;
  font-size: 15px;
  line-height: 1.75;
  color: var(--ink-soft);
}

.faq-body p:last-child {
  margin-bottom: 0;
}

/* --------------------------------------------------------------------------
   pages · 404
   -------------------------------------------------------------------------- */

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

.error-panel {
  padding: 32px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-top: 4px solid var(--brick);
  border-radius: var(--radius-md);
}

.error-code {
  margin: 0 0 6px;
  font-family: var(--font-mono);
  font-size: 14px;
  font-weight: 600;
  letter-spacing: 0.08em;
  color: var(--brick);
  font-variant-numeric: tabular-nums;
}

.error-panel h1 {
  margin: 0 0 10px;
  max-width: 24ch;
}

.error-lead {
  margin: 0 0 22px;
  max-width: 60ch;
  font-size: 16px;
  line-height: 1.75;
  color: var(--ink-soft);
}

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

.btn {
  display: inline-block;
  padding: 11px 22px;
  min-height: 44px;
  font-size: 15px;
  font-weight: 500;
  line-height: 1.5;
  text-align: center;
  text-decoration: none;
  border-radius: var(--radius-sm);
  border: 1px solid transparent;
  transition: background-color 0.16s ease, color 0.16s ease, border-color 0.16s ease;
}

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

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

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

.btn-ghost:hover {
  color: var(--green-deep);
  background: var(--green-tint);
  border-color: var(--green);
  text-decoration: none;
}

.error-routes {
  margin-top: 32px;
}

.error-routes h2 {
  margin: 0 0 12px;
  font-size: 18px;
}

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

.error-route-list li {
  margin: 0;
}

.error-route-list a {
  display: inline-block;
  padding: 9px 16px;
  min-height: 44px;
  font-size: 14px;
  line-height: 1.6;
  color: var(--green);
  background: var(--surface);
  border: 1px solid var(--line-strong);
  border-radius: var(--radius-sm);
  text-decoration: none;
}

.error-route-list a:hover {
  color: var(--green-deep);
  background: var(--green-tint);
  border-color: var(--green);
  text-decoration: none;
}

/* --------------------------------------------------------------------------
   responsive
   -------------------------------------------------------------------------- */

@media (max-width: 960px) {
  .header-inner {
    position: relative;
  }

  .nav-toggle {
    display: flex;
  }

  .primary-nav {
    flex: 1 0 100%;
    margin-left: 0;
    display: none;
    padding-bottom: 12px;
  }

  .primary-nav.is-open {
    display: block;
  }

  .primary-nav ul {
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    border-top: 1px solid rgba(255, 255, 255, 0.2);
    padding-top: 8px;
  }

  .primary-nav a {
    min-height: 48px;
    display: flex;
    align-items: center;
    padding: 10px 12px;
    font-size: 16px;
    border-bottom: 0;
    border-left: 3px solid transparent;
  }

  .primary-nav a.is-current {
    border-left-color: var(--brick);
    background: rgba(255, 255, 255, 0.08);
  }

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

  .task-columns {
    grid-template-columns: minmax(0, 1fr);
    border-top: 0;
  }

  .task-col {
    padding: 24px 0;
    border-left: 0;
    border-top: 1px solid var(--line);
  }

  .task-col:first-child {
    border-top: 0;
    padding-top: 0;
  }

  .task-col:last-child {
    padding-bottom: 0;
  }

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

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

  .page-layout,
  .layout-shell {
    grid-template-columns: minmax(0, 1fr);
    gap: 32px;
  }

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

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

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

  .revision-item {
    grid-template-columns: 120px minmax(0, 1fr);
  }

  .revision-item .revision-impact {
    grid-column: 2;
  }

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

@media (max-width: 640px) {
  :root {
    --gutter: 16px;
  }

  body {
    font-size: 16px;
    line-height: 1.7;
  }

  .home-main > section {
    padding: 32px 0;
  }

  .hero {
    padding-top: 28px !important;
  }

  .hero-scenes {
    padding: 16px 14px 6px;
  }

  .scene-card {
    grid-template-columns: 36px minmax(0, 1fr);
    gap: 12px;
    padding: 12px;
  }

  .scene-num {
    width: 36px;
  }

  .strip-tags {
    gap: 8px;
  }

  .tag {
    padding: 9px 14px;
    font-size: 14px;
  }

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

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

  .tip-num {
    font-size: 18px;
  }

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

  .compare-grid {
    grid-template-columns: minmax(0, 1fr);
    gap: 16px;
  }

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

  .check-item,
  .check-list .check-item,
  #info-checklist .check-item {
    grid-template-columns: minmax(0, 1fr);
    gap: 4px;
  }

  .check-item .check-name {
    font-size: 15px;
  }

  .info-row,
  .struct-row,
  .def-row,
  .revision-row,
  .revision-item {
    grid-template-columns: minmax(0, 1fr);
    gap: 4px;
  }

  .revision-item .revision-impact {
    grid-column: auto;
  }

  .topic-row {
    grid-template-columns: 36px minmax(0, 1fr);
    gap: 10px;
  }

  .problem-table,
  .problem-table thead,
  .problem-table tbody,
  .problem-table tr,
  .problem-table th,
  .problem-table td {
    display: block;
    width: 100%;
  }

  .problem-table thead {
    position: absolute;
    width: 1px;
    height: 1px;
    overflow: hidden;
    clip: rect(0 0 0 0);
    white-space: nowrap;
  }

  .problem-table tbody tr {
    padding: 12px 14px;
    border-bottom: 1px solid var(--line);
  }

  .problem-table tbody tr:last-child {
    border-bottom: 0;
  }

  .problem-table tbody th,
  .problem-table tbody td {
    padding: 0;
    border-bottom: 0;
  }

  .problem-table tbody th {
    margin-bottom: 4px;
    color: var(--indigo);
  }

  .toc-nav ul {
    flex-direction: column;
    gap: 0;
  }

  .toc-nav a {
    display: block;
    padding: 8px 0;
    min-height: 40px;
  }

  .error-panel {
    padding: 22px 18px;
  }

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

  .footer-bottom {
    flex-direction: column;
    align-items: flex-start;
  }

  .back-top {
    margin-left: 0;
  }

  .primary-nav a {
    min-height: 48px;
  }
}

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

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