/* ==========================================================================
   秋霞影院 · 全站样式表
   分组：base / layout / components / pages / responsive
   ========================================================================== */

/* --------------------------------------------------------------------------
   1. base —— 变量、重置、排版基线
   -------------------------------------------------------------------------- */

:root {
  --bg: #f5f6f8;
  --surface: #ffffff;
  --text: #1e2229;
  --text-soft: #5b6472;
  --line: #d9dde3;
  --line-soft: #e8ebef;
  --accent: #2f6f6a;
  --accent-soft: #eef4f3;
  --accent-line: #b9d3d0;
  --radius: 6px;
  --radius-sm: 4px;
  --wrap: 1120px;
  --gap: 20px;
}

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

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

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
    "Hiragino Sans GB", "Microsoft YaHei", "Source Han Sans SC", sans-serif;
  font-size: 16px;
  line-height: 1.75;
  font-weight: 400;
}

h1,
h2,
h3,
h4 {
  margin: 0;
  font-weight: 600;
  line-height: 1.4;
  color: var(--text);
}

p {
  margin: 0;
}

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

a {
  color: var(--accent);
  text-decoration: none;
}

a:hover,
a:focus-visible {
  text-decoration: underline;
}

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

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

button {
  font: inherit;
  color: inherit;
}

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

.skip-link {
  position: absolute;
  left: -9999px;
  top: 0;
  z-index: 60;
  padding: 10px 16px;
  background: var(--accent);
  color: #fff;
  border-radius: 0 0 var(--radius-sm) 0;
}

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

/* --------------------------------------------------------------------------
   2. layout —— 全站骨架：页头、导航、主体、面包屑、页标题、页脚
   -------------------------------------------------------------------------- */

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

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

.header-inner {
  width: 100%;
  max-width: var(--wrap);
  margin: 0 auto;
  padding: 0 24px;
  min-height: 62px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
}

.brand-logo {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-size: 18px;
  font-weight: 600;
  color: var(--text);
  letter-spacing: 0;
  white-space: nowrap;
}

.brand-logo::before {
  content: "";
  width: 10px;
  height: 10px;
  border: 2px solid var(--accent);
  border-radius: 2px;
  background: var(--accent-soft);
}

.brand-logo:hover,
.brand-logo:focus-visible {
  color: var(--accent);
  text-decoration: none;
}

.site-nav {
  display: flex;
  align-items: center;
}

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

.nav-link {
  display: inline-block;
  padding: 9px 12px;
  font-size: 15px;
  color: var(--text-soft);
  border-radius: var(--radius-sm);
  border-bottom: 2px solid transparent;
  white-space: nowrap;
}

.nav-link:hover,
.nav-link:focus-visible {
  color: var(--accent);
  background: var(--accent-soft);
  text-decoration: none;
}

.nav-link.is-current {
  color: var(--accent);
  border-bottom-color: var(--accent);
  font-weight: 600;
}

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

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

.site-main {
  flex: 1 0 auto;
  width: 100%;
  max-width: var(--wrap);
  margin: 0 auto;
  padding: 0 24px 56px;
}

.inner-main {
  padding-top: 20px;
}

.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  font-size: 13px;
  color: var(--text-soft);
  line-height: 1.6;
  padding: 4px 0 0;
}

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

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

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

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

.page-header {
  padding: 18px 0 22px;
  border-bottom: 1px solid var(--line);
  margin-bottom: 28px;
}

.page-title {
  font-size: 28px;
  font-weight: 600;
  color: var(--text);
  letter-spacing: 0;
}

.page-description {
  margin-top: 10px;
  font-size: 15px;
  line-height: 1.8;
  color: var(--text-soft);
  max-width: 76ch;
}

.page-description a {
  color: var(--accent);
}

/* 页脚 */

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

.footer-inner {
  width: 100%;
  max-width: var(--wrap);
  margin: 0 auto;
  padding: 34px 24px 24px;
  display: grid;
  grid-template-columns: 1.6fr 1fr 1.2fr;
  gap: 28px;
}

.footer-brand {
  font-size: 16px;
  font-weight: 600;
  color: var(--text);
  margin-bottom: 8px;
}

.footer-desc {
  font-size: 14px;
  line-height: 1.8;
  color: var(--text-soft);
  max-width: 42ch;
}

.footer-nav-title,
.footer-note-title {
  font-size: 14px;
  font-weight: 600;
  color: var(--text);
  margin-bottom: 10px;
}

.footer-nav-list {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.footer-nav-list a {
  font-size: 14px;
  color: var(--text-soft);
  line-height: 1.6;
}

.footer-nav-list a:hover,
.footer-nav-list a:focus-visible {
  color: var(--accent);
}

.footer-note-text {
  font-size: 14px;
  line-height: 1.8;
  color: var(--text-soft);
  margin-bottom: 12px;
}

.back-to-top {
  display: inline-block;
  font-size: 14px;
  padding: 6px 12px;
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
  color: var(--text-soft);
}

.back-to-top:hover,
.back-to-top:focus-visible {
  color: var(--accent);
  border-color: var(--accent-line);
  background: var(--accent-soft);
  text-decoration: none;
}

.footer-bottom {
  border-top: 1px solid var(--line-soft);
}

.copyright {
  width: 100%;
  max-width: var(--wrap);
  margin: 0 auto;
  padding: 14px 24px 20px;
  font-size: 13px;
  line-height: 1.7;
  color: var(--text-soft);
}

/* --------------------------------------------------------------------------
   3. components —— 通用模块：区块头、卡片、片单、表格、步骤、图注
   -------------------------------------------------------------------------- */

.section {
  padding: 34px 0;
  border-top: 1px solid var(--line);
}

.section:first-child {
  border-top: 0;
}

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

.section-title {
  font-size: 20px;
  font-weight: 600;
  color: var(--text);
}

.section-desc,
.section-lead,
.section-intro,
.section-text {
  margin-top: 8px;
  font-size: 15px;
  line-height: 1.8;
  color: var(--text-soft);
  max-width: 78ch;
}

.section-text + .section-text {
  margin-top: 12px;
}

/* 卡片通用：方向卡 / 片单 / 索引卡 / 提示卡 */

.channel-card,
.playlist-item,
.index-card,
.note-card,
.feedback-item,
.scope-block,
.organize-block,
.feedback-block {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.channel-name,
.playlist-name,
.index-card-title,
.note-card-title,
.feedback-title {
  font-size: 16px;
  font-weight: 600;
  color: var(--text);
}

.channel-scope,
.channel-fields,
.channel-field,
.playlist-scope,
.playlist-direction,
.index-card-text,
.note-card-text,
.feedback-text {
  margin-top: 8px;
  font-size: 14px;
  line-height: 1.75;
  color: var(--text-soft);
}

.field-label {
  color: var(--text);
  font-weight: 600;
  margin-right: 4px;
}

.channel-link,
.playlist-link,
.step-link,
.feedback-link {
  display: inline-block;
  margin-top: 12px;
  font-size: 14px;
  color: var(--accent);
  border-bottom: 1px solid var(--accent-line);
  padding-bottom: 1px;
}

.channel-link:hover,
.playlist-link:hover,
.step-link:hover,
.feedback-link:hover,
.channel-link:focus-visible,
.playlist-link:focus-visible,
.step-link:focus-visible,
.feedback-link:focus-visible {
  color: var(--text);
  border-bottom-color: var(--text);
  text-decoration: none;
}

/* figure 与图片约束 */

.hero-media,
.fields-media,
.section-figure,
.media-figure,
.content-figure {
  margin: 0;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
}

.hero-media img,
.fields-media img,
.section-figure img,
.media-figure img,
.content-figure img {
  width: 100%;
  height: auto;
  aspect-ratio: 16 / 9;
  object-fit: cover;
  background: var(--line-soft);
}

.hero-media figcaption,
.fields-media figcaption,
.section-figure figcaption,
.media-caption,
.figure-caption {
  padding: 10px 14px;
  font-size: 13px;
  line-height: 1.7;
  color: var(--text-soft);
  border-top: 1px solid var(--line-soft);
}

/* 字段表 */

.fields-table-wrap {
  overflow-x: auto;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.fields-table,
.field-table {
  font-size: 14px;
  line-height: 1.7;
}

.fields-caption,
.field-table-caption {
  caption-side: top;
  text-align: left;
  padding: 12px 14px;
  font-size: 13px;
  color: var(--text-soft);
  border-bottom: 1px solid var(--line-soft);
}

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

.fields-table thead th,
.field-table thead th {
  background: var(--accent-soft);
  color: var(--text);
  font-weight: 600;
  border-bottom: 1px solid var(--accent-line);
}

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

.field-name {
  width: 22%;
  color: var(--text);
  font-weight: 600;
  background: #fafbfc;
}

.field-meaning {
  width: 44%;
  color: var(--text-soft);
}

.field-rule {
  width: 34%;
  color: var(--text-soft);
}

/* 步骤清单：首页 / 内页共用结构，用父级作用域区分 */

.steps-list,
.step-list {
  display: flex;
  flex-direction: column;
  gap: 0;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
}

.step-item {
  display: flex;
  align-items: flex-start;
  gap: 14px;
  padding: 16px 18px;
  border-top: 1px solid var(--line-soft);
}

.steps-list .step-item:first-child,
.step-list .step-item:first-child {
  border-top: 0;
}

.step-index {
  flex: 0 0 auto;
  min-width: 30px;
  height: 30px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font-size: 13px;
  font-weight: 600;
  color: var(--accent);
  background: var(--accent-soft);
  border: 1px solid var(--accent-line);
  border-radius: var(--radius-sm);
}

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

.step-title {
  font-size: 15px;
  font-weight: 600;
  color: var(--text);
}

.step-text {
  margin-top: 6px;
  font-size: 14px;
  line-height: 1.75;
  color: var(--text-soft);
  max-width: 72ch;
}

.step-body .step-text {
  margin-top: 6px;
}

.step-body .step-link {
  margin-top: 8px;
}

/* --------------------------------------------------------------------------
   4. pages —— 各页专属模块
   -------------------------------------------------------------------------- */

/* 4.1 首页 */

.home-main {
  padding-top: 26px;
}

.hero-block {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 28px;
}

.hero-inner {
  display: grid;
  grid-template-columns: minmax(0, 1.05fr) minmax(0, 0.95fr);
  grid-template-areas:
    "intro figure"
    "paths figure";
  gap: 24px 32px;
  align-items: start;
}

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

.hero-eyebrow {
  font-size: 13px;
  color: var(--accent);
  letter-spacing: 0;
  margin-bottom: 8px;
}

.hero-title {
  font-size: 28px;
  font-weight: 600;
  line-height: 1.4;
  color: var(--text);
}

.hero-desc {
  margin-top: 12px;
  font-size: 15px;
  line-height: 1.8;
  color: var(--text-soft);
  max-width: 60ch;
}

.hero-points {
  margin-top: 16px;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

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

.hero-points li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 10px;
  width: 7px;
  height: 7px;
  border: 1px solid var(--accent);
  border-radius: 2px;
  background: var(--accent-soft);
}

.hero-figure {
  grid-area: figure;
  min-width: 0;
}

.hero-paths {
  grid-area: paths;
  min-width: 0;
  padding-top: 18px;
  border-top: 1px solid var(--line-soft);
}

.hero-paths-title {
  font-size: 15px;
  font-weight: 600;
  color: var(--text);
  margin-bottom: 12px;
}

.path-list {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 12px;
}

.path-item {
  min-width: 0;
}

.path-link {
  display: block;
  height: 100%;
  padding: 14px;
  background: var(--accent-soft);
  border: 1px solid var(--accent-line);
  border-radius: var(--radius);
  color: var(--text);
  font-size: 14px;
  line-height: 1.7;
}

.path-link:hover,
.path-link:focus-visible {
  background: #e4efee;
  border-color: var(--accent);
  color: var(--accent);
  text-decoration: none;
}

.path-name {
  display: block;
  font-weight: 600;
  color: var(--text);
}

.path-link:hover .path-name,
.path-link:focus-visible .path-name {
  color: var(--accent);
}

.path-note {
  display: block;
  margin-top: 4px;
  font-size: 13px;
  color: var(--text-soft);
}

/* 题材频道方向总览 */

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

.channel-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(210px, 1fr));
  gap: 16px;
}

.channel-grid .channel-card {
  padding: 18px;
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  min-width: 0;
}

.channel-grid .channel-card .channel-link {
  margin-top: auto;
  padding-top: 12px;
}

.channel-grid .channel-card:hover,
.channel-grid .channel-card:focus-within {
  border-color: var(--accent-line);
  background: #fbfdfd;
}

/* 专题片单速览 */

.playlist-list {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 16px;
}

.playlist-list .playlist-item {
  padding: 18px;
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  min-width: 0;
}

.playlist-list .playlist-item .playlist-link {
  margin-top: auto;
  padding-top: 12px;
}

.playlist-list .playlist-item:hover,
.playlist-list .playlist-item:focus-within {
  border-color: var(--accent-line);
  background: #fbfdfd;
}

/* 首页字段说明：左表右图 */

.fields-layout {
  display: grid;
  grid-template-columns: minmax(0, 1.35fr) minmax(0, 1fr);
  gap: 24px;
  align-items: start;
}

.fields-media {
  min-width: 0;
}

.fields-media img {
  aspect-ratio: 4 / 3;
}

/* 收录边界与反馈 */

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

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

.boundary-subtitle {
  font-size: 15px;
  font-weight: 600;
  color: var(--text);
  margin-bottom: 10px;
}

.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(--text-soft);
}

.boundary-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 11px;
  width: 6px;
  height: 1px;
  background: var(--accent);
}

.feedback-block {
  margin-top: 20px;
  padding: 18px;
}

.feedback-block .feedback-link {
  margin-top: 10px;
}

/* 4.2 题材频道页 */

.page-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 240px;
  gap: 28px;
  align-items: start;
}

.sidebar-left .page-layout {
  grid-template-columns: 240px minmax(0, 1fr);
}

.channel-sidebar {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 16px;
  min-width: 0;
}

.sidebar-title {
  font-size: 15px;
  font-weight: 600;
  color: var(--text);
  padding-bottom: 10px;
  margin-bottom: 10px;
  border-bottom: 1px solid var(--line-soft);
}

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

.sidebar-list a {
  display: block;
  padding: 8px 10px;
  font-size: 14px;
  color: var(--text-soft);
  border-left: 2px solid transparent;
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
}

.sidebar-list a:hover,
.sidebar-list a:focus-visible {
  color: var(--accent);
  background: var(--accent-soft);
  border-left-color: var(--accent);
  text-decoration: none;
}

.channel-group,
.channel-flow {
  min-width: 0;
}

.channel-group .section-title,
.channel-flow .section-title {
  padding-bottom: 10px;
  border-bottom: 1px solid var(--line);
}

.channel-group .section-figure {
  margin-top: 18px;
}

.channel-group .channel-card {
  margin-top: 16px;
  padding: 18px;
  scroll-margin-top: 80px;
}

.channel-group .channel-card .channel-link {
  margin-top: 12px;
}

.channel-group .channel-card:hover,
.channel-group .channel-card:focus-within {
  border-color: var(--accent-line);
  background: #fbfdfd;
}

.channel-flow {
  margin-top: 34px;
  padding-top: 30px;
  border-top: 1px solid var(--line);
}

.channel-flow .step-list {
  margin-top: 16px;
}

/* 4.3 专题片单页 */

.section-media .media-figure {
  margin-top: 16px;
}

.section-playlists {
  padding-top: 30px;
}

.section-playlists .playlist-item {
  margin-top: 16px;
  padding: 18px;
}

.section-playlists .playlist-item:first-of-type {
  margin-top: 18px;
}

.section-playlists .playlist-name a {
  color: var(--text);
}

.section-playlists .playlist-name a:hover,
.section-playlists .playlist-name a:focus-visible {
  color: var(--accent);
}

.section-playlists .playlist-item:hover,
.section-playlists .playlist-item:focus-within {
  border-color: var(--accent-line);
  background: #fbfdfd;
}

.section-organize .organize-block {
  margin-top: 16px;
  padding: 18px;
}

.section-organize .organize-block p {
  font-size: 14px;
  line-height: 1.8;
  color: var(--text-soft);
  max-width: 78ch;
}

.section-organize .organize-block p + p {
  margin-top: 12px;
}

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

/* 4.4 剧集目录页 */

.section-figure .content-figure {
  margin-top: 16px;
}

.section-fields .field-table {
  margin-top: 16px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
}

.section-index .index-grid {
  margin-top: 16px;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 16px;
}

.index-card {
  padding: 18px;
  min-width: 0;
}

.index-card:hover,
.index-card:focus-within {
  border-color: var(--accent-line);
  background: #fbfdfd;
}

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

.section-notes .note-grid {
  margin-top: 16px;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 16px;
}

.note-card {
  padding: 18px;
  min-width: 0;
  border-left: 3px solid var(--accent-line);
}

/* 4.5 查阅指引页 */

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

.steps-section .section-figure {
  margin-top: 20px;
}

.scope-section .scope-grid {
  margin-top: 16px;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 20px;
}

.scope-block {
  padding: 18px;
  min-width: 0;
}

.scope-title {
  font-size: 15px;
  font-weight: 600;
  color: var(--text);
  padding-bottom: 10px;
  margin-bottom: 12px;
  border-bottom: 1px solid var(--line-soft);
}

.scope-in .scope-title {
  color: var(--accent);
}

.scope-out .scope-title {
  color: var(--text-soft);
}

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

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

.scope-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 11px;
  width: 6px;
  height: 1px;
  background: var(--line);
}

.scope-in .scope-list li::before {
  background: var(--accent);
}

.scope-note {
  margin-top: 16px;
  padding: 14px 16px;
  background: var(--accent-soft);
  border: 1px solid var(--accent-line);
  border-radius: var(--radius);
  font-size: 14px;
  line-height: 1.8;
  color: var(--text-soft);
}

.feedback-section .feedback-grid {
  margin-top: 16px;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 16px;
}

.feedback-item {
  padding: 18px;
  min-width: 0;
}

.faq-section .faq-list {
  margin-top: 16px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
}

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

.faq-item:first-child {
  border-top: 0;
}

.faq-question {
  padding: 15px 18px;
  font-size: 15px;
  font-weight: 600;
  color: var(--text);
  cursor: pointer;
  list-style: none;
  position: relative;
  padding-right: 46px;
}

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

.faq-question::after {
  content: "";
  position: absolute;
  right: 18px;
  top: 50%;
  width: 9px;
  height: 9px;
  margin-top: -6px;
  border-right: 2px solid var(--accent);
  border-bottom: 2px solid var(--accent);
  transform: rotate(45deg);
  transition: transform 0.2s ease;
}

.faq-item[open] .faq-question::after {
  transform: rotate(-135deg);
  margin-top: -2px;
}

.faq-question:hover {
  background: var(--accent-soft);
}

.faq-answer {
  padding: 0 18px 18px;
  font-size: 14px;
  line-height: 1.8;
  color: var(--text-soft);
  max-width: 78ch;
}

/* 4.6 404 页 */

.error-main {
  padding-top: 40px;
}

.error-block {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 32px 28px;
}

.error-code {
  font-size: 13px;
  color: var(--accent);
  margin-bottom: 8px;
}

.error-block h1 {
  font-size: 26px;
  font-weight: 600;
  color: var(--text);
}

.error-text {
  margin-top: 12px;
  font-size: 15px;
  line-height: 1.8;
  color: var(--text-soft);
  max-width: 66ch;
}

.error-home-link {
  display: inline-block;
  margin-top: 18px;
  padding: 10px 18px;
  background: var(--accent);
  color: #fff;
  border-radius: var(--radius-sm);
  font-size: 15px;
}

.error-home-link:hover,
.error-home-link:focus-visible {
  background: #265b57;
  color: #fff;
  text-decoration: none;
}

.error-paths {
  margin-top: 28px;
}

.error-paths h2 {
  font-size: 20px;
  font-weight: 600;
  color: var(--text);
  padding-bottom: 10px;
  border-bottom: 1px solid var(--line);
}

.error-path-list {
  margin-top: 16px;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 16px;
}

.error-path-item {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 16px;
  min-width: 0;
}

.error-path-item a {
  display: inline-block;
  font-size: 15px;
  font-weight: 600;
  color: var(--accent);
}

.error-path-item p {
  margin-top: 8px;
  font-size: 14px;
  line-height: 1.75;
  color: var(--text-soft);
}

/* --------------------------------------------------------------------------
   5. responsive —— 960px 与 640px 断点
   -------------------------------------------------------------------------- */

@media (max-width: 960px) {
  .header-inner {
    padding: 0 18px;
    flex-wrap: wrap;
    min-height: 58px;
  }

  .nav-toggle {
    display: inline-flex;
  }

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

  .nav-list {
    display: none;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    width: 100%;
    padding: 8px 0 12px;
    border-top: 1px solid var(--line);
  }

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

  .nav-list li {
    width: 100%;
  }

  .nav-link {
    display: block;
    min-height: 44px;
    padding: 12px 4px;
    border-bottom: 1px solid var(--line-soft);
    border-radius: 0;
    font-size: 15px;
  }

  .nav-link.is-current {
    border-bottom-color: var(--line-soft);
    border-left: 2px solid var(--accent);
    padding-left: 10px;
  }

  .site-main {
    padding: 0 18px 44px;
  }

  .hero-inner {
    grid-template-columns: minmax(0, 1fr);
    grid-template-areas:
      "intro"
      "figure"
      "paths";
    gap: 20px;
  }

  .hero-block {
    padding: 22px;
  }

  .path-list {
    grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
  }

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

  .page-layout,
  .sidebar-left .page-layout {
    grid-template-columns: minmax(0, 1fr);
    gap: 22px;
  }

  .channel-sidebar {
    padding: 14px;
  }

  .sidebar-list {
    flex-direction: row;
    flex-wrap: wrap;
    gap: 8px;
  }

  .sidebar-list a {
    border-left: 0;
    border: 1px solid var(--line);
    border-radius: var(--radius-sm);
    padding: 8px 12px;
    min-height: 40px;
  }

  .sidebar-list a:hover,
  .sidebar-list a:focus-visible {
    border-color: var(--accent);
  }

  .footer-inner {
    grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
    gap: 24px;
    padding: 30px 18px 22px;
  }

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

  .copyright {
    padding: 14px 18px 20px;
  }
}

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

  .brand-logo {
    font-size: 17px;
  }

  .site-main {
    padding: 0 14px 36px;
  }

  .inner-main {
    padding-top: 16px;
  }

  .page-header {
    padding: 14px 0 18px;
    margin-bottom: 22px;
  }

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

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

  .hero-block {
    padding: 18px;
  }

  .section {
    padding: 26px 0;
  }

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

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

  .path-link {
    min-height: 44px;
  }

  .channel-grid,
  .playlist-list,
  .index-grid,
  .note-grid,
  .feedback-grid,
  .error-path-list {
    grid-template-columns: minmax(0, 1fr);
  }

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

  .fields-table-wrap {
    overflow-x: visible;
  }

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

  .fields-table thead,
  .field-table thead {
    display: none;
  }

  .fields-table tbody tr,
  .field-table tbody tr {
    padding: 14px 16px;
    border-bottom: 1px solid var(--line-soft);
  }

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

  .fields-table th,
  .fields-table td,
  .field-table th,
  .field-table td {
    padding: 0;
    border-bottom: 0;
  }

  .field-name {
    width: auto;
    background: transparent;
    font-size: 15px;
    margin-bottom: 6px;
  }

  .field-meaning,
  .field-rule {
    width: auto;
  }

  .field-meaning + .field-rule {
    margin-top: 6px;
  }

  .field-meaning::before {
    content: "含义：";
    color: var(--text);
    font-weight: 600;
  }

  .field-rule::before {
    content: "填写要求：";
    color: var(--text);
    font-weight: 600;
  }

  .fields-caption,
  .field-table-caption {
    padding: 12px 16px;
  }

  .step-item {
    padding: 14px;
    gap: 12px;
  }

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

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

  .error-home-link {
    display: block;
    text-align: center;
    min-height: 44px;
    line-height: 1.6;
  }

  .footer-inner {
    grid-template-columns: minmax(0, 1fr);
    gap: 20px;
    padding: 26px 14px 20px;
  }

  .footer-nav-list {
    gap: 0;
  }

  .footer-nav-list a {
    display: block;
    min-height: 44px;
    padding: 10px 0;
    border-bottom: 1px solid var(--line-soft);
  }

  .back-to-top {
    min-height: 44px;
    padding: 11px 14px;
  }

  .copyright {
    padding: 14px 14px 20px;
  }
}

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

  .faq-question::after {
    transition: none;
  }
}