/* ==========================================================================
   秋霞在线视频 · 全站样式表
   base → layout → components → pages → responsive
   ========================================================================== */

/* ==========================================================================
   1. base
   ========================================================================== */

:root {
  --ink: #1c1f24;
  --ink-soft: #4a5058;
  --accent: #b4532a;
  --bg: #f5f3ef;
  --line: #d8d3cb;
  --surface: #fbfaf8;
  --container: 1120px;
  --body-col: 720px;
  --aside-col: 320px;
  --gap: 40px;
  --radius: 6px;
  --font-sans: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Noto Sans SC", sans-serif;
}

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

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

body {
  margin: 0;
  background-color: var(--bg);
  color: var(--ink-soft);
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.75;
  text-rendering: optimizeLegibility;
}

h1,
h2,
h3,
h4 {
  margin: 0 0 12px;
  color: var(--ink);
  font-weight: 600;
  line-height: 1.3;
}

h1 {
  font-size: 40px;
  line-height: 1.2;
}

h2 {
  font-size: 26px;
}

h3 {
  font-size: 20px;
}

p {
  margin: 0 0 14px;
}

p:last-child {
  margin-bottom: 0;
}

ul,
ol {
  margin: 0 0 14px;
  padding-left: 20px;
}

li {
  margin-bottom: 6px;
}

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

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

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

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

figure {
  margin: 0;
}

figcaption {
  margin-top: 10px;
  color: var(--ink-soft);
  font-size: 14px;
  line-height: 1.7;
}

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

th,
td {
  text-align: left;
  vertical-align: top;
}

strong {
  color: var(--ink);
  font-weight: 600;
}

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

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

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

.site-header {
  background-color: var(--bg);
  border-bottom: 1px solid var(--line);
}

.site-header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  max-width: var(--container);
  margin: 0 auto;
  padding: 18px 20px;
}

.site-brand {
  color: var(--ink);
  font-size: 20px;
  font-weight: 600;
  letter-spacing: 0.02em;
  white-space: nowrap;
}

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

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

.nav-list {
  display: flex;
  align-items: center;
  gap: 26px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.nav-list li {
  margin: 0;
}

.nav-list a {
  display: inline-block;
  padding: 6px 0;
  color: var(--ink);
  font-size: 15px;
  border-bottom: 2px solid transparent;
}

.nav-list a:hover,
.nav-list a:focus-visible {
  color: var(--accent);
  border-bottom-color: var(--accent);
  text-decoration: none;
}

.nav-list a.is-current {
  color: var(--accent);
  border-bottom-color: var(--accent);
}

.nav-toggle {
  display: none;
  padding: 10px 14px;
  min-height: 44px;
  background-color: transparent;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  color: var(--ink);
  font-family: inherit;
  font-size: 15px;
  cursor: pointer;
}

.nav-toggle:hover {
  border-color: var(--accent);
  color: var(--accent);
}

.site-main {
  max-width: var(--container);
  margin: 0 auto;
  padding: 40px 20px 64px;
}

.inner-main {
  padding-top: 28px;
}

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

.site-footer-inner {
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr 1fr;
  gap: var(--gap);
  max-width: var(--container);
  margin: 0 auto;
  padding: 48px 20px 40px;
}

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

.footer-name {
  margin-bottom: 8px;
  color: var(--ink);
  font-size: 18px;
  font-weight: 600;
}

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

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

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

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

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

.footer-col a {
  color: var(--ink-soft);
  font-size: 14px;
}

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

.footer-copy {
  margin-top: 16px;
  padding-top: 14px;
  border-top: 1px solid var(--line);
  color: var(--ink-soft);
  font-size: 13px;
  line-height: 1.7;
}

/* ==========================================================================
   3. components · 通用组件
   ========================================================================== */

.section {
  margin-bottom: 56px;
}

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

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

.section-desc,
.section-lead,
.section-intro {
  max-width: var(--body-col);
  color: var(--ink-soft);
  font-size: 15px;
  line-height: 1.75;
}

.section-lead,
.section-intro {
  margin-bottom: 20px;
}

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

.section-more a::after {
  content: " →";
  color: var(--accent);
}

.section-note {
  margin-top: 16px;
  font-size: 14px;
}

/* 按钮 */
.btn {
  display: inline-block;
  padding: 12px 22px;
  min-height: 44px;
  border: 1px solid var(--accent);
  border-radius: var(--radius);
  font-size: 15px;
  line-height: 1.4;
  text-align: center;
}

.btn-primary {
  background-color: var(--accent);
  color: #fdfbf9;
}

.btn-primary:hover,
.btn-primary:focus-visible {
  background-color: #98431f;
  border-color: #98431f;
  color: #fdfbf9;
  text-decoration: none;
}

.btn-ghost {
  background-color: transparent;
  color: var(--accent);
}

.btn-ghost:hover,
.btn-ghost:focus-visible {
  background-color: rgba(180, 83, 42, 0.08);
  text-decoration: none;
}

/* 面包屑 */
.breadcrumb {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: 20px;
  color: var(--ink-soft);
  font-size: 14px;
}

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

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

/* 页面标题区 */
.page-header {
  margin-bottom: 40px;
  padding-bottom: 24px;
  border-bottom: 1px solid var(--line);
}

.page-header .page-title {
  margin-bottom: 12px;
}

.page-description,
.page-lead {
  max-width: var(--body-col);
  color: var(--ink-soft);
  font-size: 16px;
  line-height: 1.75;
}

.page-lead {
  margin-top: 12px;
}

/* 表格 */
.table-scroll {
  overflow-x: auto;
  border-top: 1px solid var(--line);
}

.data-table {
  min-width: 640px;
  font-size: 14px;
  line-height: 1.6;
}

.data-table caption {
  padding: 12px 0;
  color: var(--ink-soft);
  font-size: 14px;
  text-align: left;
}

.data-table thead th {
  padding: 12px 16px 12px 0;
  border-bottom: 1px solid var(--line);
  color: var(--ink);
  font-weight: 600;
  white-space: nowrap;
}

.data-table tbody th {
  padding: 16px 16px 16px 0;
  border-bottom: 1px solid var(--line);
  color: var(--ink);
  font-weight: 600;
}

.data-table tbody td {
  padding: 16px 16px 16px 0;
  border-bottom: 1px solid var(--line);
}

.data-table tbody tr:last-child th,
.data-table tbody tr:last-child td {
  border-bottom: 1px solid var(--line);
}

.data-table tbody tr:hover th,
.data-table tbody tr:hover td {
  background-color: rgba(180, 83, 42, 0.04);
}

/* 相关入口列表 */
.related-list {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 16px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.related-list li {
  margin: 0;
  padding: 16px 18px;
  background-color: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.related-list a {
  font-size: 15px;
  font-weight: 600;
}

.related-list p {
  margin-top: 6px;
  color: var(--ink-soft);
  font-size: 14px;
  line-height: 1.7;
}

/* 图片容器统一约束 */
.hero-media img,
.topic-media img,
.topic-cover img,
.channel-figure img,
.guide-figure img,
.related-figure img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  border-radius: var(--radius);
}

/* ==========================================================================
   4. pages · 首页
   ========================================================================== */

.site-notice {
  margin: 0;
  padding: 10px 20px;
  background-color: var(--ink);
  color: #e8e4dd;
  font-size: 14px;
  line-height: 1.7;
  text-align: center;
}

.home-main {
  padding-top: 48px;
}

/* 首屏 */
.hero {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
  gap: var(--gap);
  align-items: center;
  margin-bottom: 64px;
}

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

.hero-text .page-title {
  margin-bottom: 16px;
}

.hero-lead {
  max-width: 520px;
  color: var(--ink-soft);
  font-size: 17px;
  line-height: 1.8;
}

.hero-facts {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 16px;
  margin: 24px 0;
  padding: 0;
  list-style: none;
}

.hero-facts li {
  margin: 0;
  padding-top: 12px;
  border-top: 2px solid var(--line);
  color: var(--ink-soft);
  font-size: 14px;
  line-height: 1.7;
}

.hero-facts strong {
  display: block;
  margin-bottom: 4px;
  font-size: 15px;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
  margin-top: 8px;
}

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

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

/* 频道总览表 */
.channel-table tbody th {
  width: 96px;
}

.channel-table td:nth-child(1) {
  min-width: 120px;
  color: var(--ink);
}

.channel-table td:nth-child(2) {
  min-width: 240px;
}

.channel-table td:nth-child(3) {
  min-width: 240px;
}

.channel-table td:nth-child(4) {
  min-width: 120px;
  white-space: nowrap;
}

/* 专题卡（首页两列） */
.section-topics .topic-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 28px;
}

.section-topics .topic-card {
  display: flex;
  flex-direction: column;
  min-width: 0;
  padding-bottom: 18px;
  border-bottom: 1px solid var(--line);
}

.section-topics .topic-media {
  margin-bottom: 16px;
}

.section-topics .topic-media img {
  aspect-ratio: 16 / 10;
}

.section-topics .topic-name {
  margin-bottom: 8px;
}

.section-topics .topic-desc {
  color: var(--ink-soft);
  font-size: 15px;
}

.section-topics .topic-path {
  margin-top: auto;
  padding-top: 12px;
  font-size: 14px;
}

/* 字段与边界 */
.field-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
  gap: var(--gap);
}

.field-col,
.boundary-col {
  min-width: 0;
}

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

.field-list dt {
  padding-top: 12px;
  color: var(--ink);
  font-weight: 600;
  font-size: 15px;
}

.field-list dd {
  margin: 4px 0 0;
  padding-bottom: 12px;
  border-bottom: 1px solid var(--line);
  color: var(--ink-soft);
  font-size: 14px;
  line-height: 1.7;
}

.boundary-cover,
.boundary-exclude {
  padding: 16px 18px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  font-size: 15px;
  line-height: 1.75;
}

.boundary-cover {
  margin-bottom: 16px;
  background-color: var(--surface);
}

.boundary-exclude {
  background-color: transparent;
}

.boundary-cover strong,
.boundary-exclude strong {
  display: block;
  margin-bottom: 6px;
}

.boundary-more {
  margin-top: 16px;
  font-size: 14px;
}

/* 整理记录速览 */
.record-groups {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 28px;
}

.record-group {
  min-width: 0;
}

.record-group h3 {
  margin-bottom: 12px;
  padding-bottom: 8px;
  border-bottom: 2px solid var(--ink);
  font-size: 17px;
}

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

.record-list li {
  margin: 0;
  padding: 10px 0;
  border-bottom: 1px solid var(--line);
  font-size: 14px;
  line-height: 1.7;
}

.record-list time {
  display: block;
  color: var(--accent);
  font-size: 13px;
}

/* 站内页面索引 */
.index-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 24px;
}

.index-col {
  min-width: 0;
  padding-top: 14px;
  border-top: 2px solid var(--ink);
}

.index-col h3 {
  margin-bottom: 8px;
  font-size: 17px;
}

.index-col p {
  color: var(--ink-soft);
  font-size: 14px;
  line-height: 1.7;
}

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

.channel-table-section .table-scroll {
  margin-bottom: 20px;
}

.channel-fields-section .field-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 24px;
}

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

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

.field-item p {
  font-size: 14px;
  line-height: 1.7;
}

.field-example {
  margin-top: 10px;
  padding-top: 10px;
  border-top: 1px solid var(--line);
  color: var(--ink);
  font-size: 13px;
}

.channel-choose-section .step-list {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 24px;
  margin: 0;
  padding: 0;
  list-style: none;
  counter-reset: channel-step;
}

.channel-choose-section .step-item {
  min-width: 0;
  padding-top: 16px;
  border-top: 2px solid var(--accent);
  counter-increment: channel-step;
}

.channel-choose-section .step-item h3 {
  font-size: 17px;
}

.channel-choose-section .step-item h3::before {
  content: counter(channel-step) ". ";
  color: var(--accent);
}

.channel-choose-section .step-item p {
  font-size: 14px;
  line-height: 1.7;
}

.channel-figure {
  margin: 0 0 56px;
}

.channel-figure img {
  aspect-ratio: 21 / 9;
}

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

.topics-list h2,
.topic-channel-map h2,
.reading-order h2,
.related-entry h2,
.records-section h2,
.records-types h2,
.records-archive h2,
.related-section h2 {
  margin-bottom: 8px;
}

.topics-list,
.topic-channel-map,
.reading-order,
.related-entry,
.records-section,
.records-types,
.records-archive,
.related-section {
  margin-bottom: 56px;
}

.topics-list .topic-card {
  display: grid;
  grid-template-columns: 300px minmax(0, 1fr);
  gap: 28px;
  align-items: start;
  margin-bottom: 32px;
  padding-bottom: 28px;
  border-bottom: 1px solid var(--line);
}

.topics-list .topic-cover img {
  aspect-ratio: 4 / 3;
}

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

.topics-list .topic-body .topic-name {
  margin-bottom: 10px;
}

.topics-list .topic-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 20px;
  margin: 14px 0;
  padding: 0;
  list-style: none;
}

.topics-list .topic-meta li {
  margin: 0;
  color: var(--ink-soft);
  font-size: 14px;
}

.topics-list .topic-meta li::before {
  content: "· ";
  color: var(--accent);
}

.topics-list .topic-entry {
  display: inline-block;
  margin-top: 6px;
  font-size: 15px;
  font-weight: 600;
}

.topics-list .topic-entry::after {
  content: " →";
}

.topic-channel-map .data-table tbody th {
  width: 220px;
}

.order-steps {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 24px;
  margin: 0;
  padding: 0;
  list-style: none;
  counter-reset: reading-step;
}

.order-step {
  min-width: 0;
  padding-top: 16px;
  border-top: 2px solid var(--ink);
  counter-increment: reading-step;
}

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

.order-step h3::before {
  content: counter(reading-step) ". ";
  color: var(--accent);
}

.order-step p {
  font-size: 14px;
  line-height: 1.7;
}

/* ==========================================================================
   7. pages · 观看指引
   ========================================================================== */

.guide-prep,
.guide-fields,
.guide-faq,
.guide-feedback {
  margin-bottom: 56px;
}

.prep-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 24px;
}

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

.prep-index {
  margin-bottom: 8px;
  color: var(--accent);
  font-size: 13px;
  font-weight: 600;
}

.prep-item h3 {
  margin-bottom: 10px;
  font-size: 17px;
}

.prep-item p {
  font-size: 14px;
  line-height: 1.7;
}

.fields-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr) var(--aside-col);
  gap: var(--gap);
  align-items: start;
}

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

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

.guide-figure img {
  aspect-ratio: 16 / 9;
}

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

.fields-body h3 {
  margin-top: 20px;
  padding-top: 16px;
  border-top: 1px solid var(--line);
  font-size: 17px;
}

.fields-body h3:first-child {
  margin-top: 0;
  padding-top: 0;
  border-top: 0;
}

.fields-body p {
  font-size: 15px;
}

.fields-aside {
  min-width: 0;
  padding: 20px;
  background-color: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.fields-aside h3 {
  margin-bottom: 12px;
  font-size: 17px;
}

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

.field-quick dt {
  padding-top: 10px;
  color: var(--ink);
  font-size: 14px;
  font-weight: 600;
}

.field-quick dd {
  margin: 2px 0 0;
  padding-bottom: 10px;
  border-bottom: 1px solid var(--line);
  color: var(--ink-soft);
  font-size: 13px;
  line-height: 1.7;
}

.aside-note {
  margin-top: 14px;
  font-size: 13px;
}

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

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

.boundary-block .boundary-col h3 {
  font-size: 17px;
}

.boundary-list {
  margin: 0;
  padding-left: 18px;
}

.boundary-list li {
  margin-bottom: 8px;
  font-size: 14px;
  line-height: 1.7;
}

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

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

.faq-item summary {
  position: relative;
  padding: 16px 32px 16px 0;
  color: var(--ink);
  font-size: 16px;
  font-weight: 600;
  cursor: pointer;
  list-style: none;
}

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

.faq-item summary::after {
  content: "+";
  position: absolute;
  right: 4px;
  top: 50%;
  transform: translateY(-50%);
  color: var(--accent);
  font-size: 20px;
  font-weight: 400;
}

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

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

.faq-item p {
  padding: 0 32px 18px 0;
  color: var(--ink-soft);
  font-size: 15px;
}

.feedback-body {
  max-width: var(--body-col);
  padding: 22px;
  background-color: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.feedback-body > p {
  font-size: 15px;
}

.feedback-steps {
  margin: 14px 0 0;
  padding-left: 20px;
}

.feedback-steps li {
  margin-bottom: 8px;
  font-size: 15px;
}

/* ==========================================================================
   8. pages · 整理记录
   ========================================================================== */

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

.record-month-title {
  margin-bottom: 16px;
  padding-bottom: 8px;
  border-bottom: 2px solid var(--ink);
  font-size: 19px;
}

.records-section .record-list {
  margin: 0;
  padding: 0;
  list-style: none;
}

.records-section .record-item {
  display: grid;
  grid-template-columns: 140px 96px minmax(0, 1fr);
  gap: 20px;
  align-items: start;
  margin: 0;
  padding: 14px 0;
  border-bottom: 1px solid var(--line);
}

.records-section .record-item:last-child {
  border-bottom: 0;
}

.records-section .record-date {
  color: var(--ink);
  font-size: 14px;
}

.records-section .record-type {
  display: inline-block;
  padding: 2px 10px;
  border-radius: var(--radius);
  font-size: 13px;
  line-height: 1.6;
  text-align: center;
}

.records-section .record-type-add {
  background-color: rgba(180, 83, 42, 0.12);
  color: #8f3f1d;
}

.records-section .record-type-adjust {
  background-color: rgba(28, 31, 36, 0.08);
  color: var(--ink);
}

.records-section .record-type-field {
  background-color: rgba(74, 80, 88, 0.12);
  color: var(--ink-soft);
}

.records-section .record-text {
  margin: 0;
  font-size: 15px;
  line-height: 1.75;
}

.type-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 24px;
}

.type-card {
  min-width: 0;
  padding: 20px;
  background-color: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.type-card h3 {
  margin-bottom: 8px;
  font-size: 17px;
}

.type-card p {
  font-size: 14px;
  line-height: 1.7;
}

.archive-nav {
  padding-top: 16px;
  border-top: 1px solid var(--line);
}

.archive-list {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.archive-list li {
  margin: 0;
}

.archive-list a {
  display: inline-block;
  padding: 8px 16px;
  min-height: 40px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  color: var(--ink);
  font-size: 14px;
}

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

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

.related-figure img {
  aspect-ratio: 21 / 9;
}

/* ==========================================================================
   9. pages · 404
   ========================================================================== */

.error-main {
  padding-top: 72px;
  padding-bottom: 88px;
}

.error-block {
  max-width: 720px;
  margin: 0 auto;
  text-align: left;
}

.error-code {
  margin-bottom: 10px;
  color: var(--accent);
  font-size: 15px;
  font-weight: 600;
}

.error-block h1 {
  margin-bottom: 16px;
}

.error-text {
  font-size: 16px;
  line-height: 1.75;
}

.error-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
  margin: 26px 0 34px;
}

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

.error-links li {
  margin: 0;
  padding: 16px 18px;
  background-color: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.error-links a {
  font-size: 15px;
  font-weight: 600;
}

/* ==========================================================================
   10. responsive
   ========================================================================== */

@media (max-width: 1024px) {
  .site-footer-inner {
    grid-template-columns: 1fr 1fr;
    gap: 32px;
  }

  .hero {
    gap: 32px;
  }

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

  .channel-fields-section .field-grid,
  .prep-grid,
  .type-grid,
  .record-groups,
  .index-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .index-grid {
    gap: 20px;
  }
}

@media (max-width: 768px) {
  h1,
  .page-title {
    font-size: 28px;
    line-height: 1.25;
  }

  h2 {
    font-size: 22px;
  }

  h3 {
    font-size: 18px;
  }

  .site-header-inner {
    flex-wrap: wrap;
    padding: 14px 20px;
  }

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

  .site-nav {
    flex-basis: 100%;
    justify-content: flex-start;
  }

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

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

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

  .nav-list a {
    display: block;
    padding: 14px 4px;
    min-height: 48px;
    border-bottom: 0;
  }

  .nav-list a.is-current {
    border-bottom: 0;
  }

  .site-main {
    padding: 28px 20px 48px;
  }

  .home-main {
    padding-top: 32px;
  }

  .hero {
    grid-template-columns: minmax(0, 1fr);
    gap: 24px;
    margin-bottom: 48px;
  }

  .hero-media {
    order: -1;
  }

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

  .hero-facts {
    grid-template-columns: minmax(0, 1fr);
    gap: 12px;
  }

  .section {
    margin-bottom: 44px;
  }

  .section-topics .topic-grid,
  .topics-list .topic-card,
  .order-steps,
  .channel-choose-section .step-list,
  .type-grid,
  .prep-grid,
  .record-groups,
  .index-grid,
  .boundary-block,
  .error-links {
    grid-template-columns: minmax(0, 1fr);
  }

  .topics-list .topic-card {
    gap: 18px;
  }

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

  .records-section .record-item {
    grid-template-columns: minmax(0, 1fr);
    gap: 8px;
  }

  .records-section .record-type {
    justify-self: start;
  }

  .site-footer-inner {
    grid-template-columns: minmax(0, 1fr);
    gap: 28px;
    padding: 36px 20px 32px;
  }

  .error-main {
    padding-top: 48px;
    padding-bottom: 64px;
  }
}

@media (max-width: 480px) {
  .site-notice {
    padding: 10px 16px;
    font-size: 13px;
  }

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

  .btn {
    width: 100%;
  }

  .faq-item summary {
    padding-right: 28px;
  }

  .feedback-body {
    padding: 18px;
  }
}

/* 滚动淡入增强：默认可见，仅在支持动效且用户未要求减弱时生效 */
@media (prefers-reduced-motion: no-preference) {
  .section,
  .hero {
    animation: fade-up 0.5s ease-out both;
  }

  @keyframes fade-up {
    from {
      transform: translateY(8px);
    }

    to {
      transform: translateY(0);
    }
  }
}