/* ============================================================
   Base
   ============================================================ */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  font-size: 16px;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
    "Hiragino Sans GB", "Microsoft YaHei", "Helvetica Neue", Helvetica, Arial,
    sans-serif;
  font-size: 15px;
  line-height: 1.7;
  color: #222222;
  background-color: #f5f6f7;
}

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

a {
  color: #1f6feb;
  text-decoration: none;
}

a:hover {
  text-decoration: underline;
}

ul,
ol {
  list-style: none;
}

h1,
h2,
h3,
h4 {
  font-weight: 600;
  line-height: 1.4;
}

h1 {
  font-size: 28px;
}

h2 {
  font-size: 18px;
}

h3 {
  font-size: 16px;
}

p {
  margin-bottom: 0;
}

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

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

/* ============================================================
   Layout 通用容器
   ============================================================ */
.site-header {
  background: #ffffff;
  border-bottom: 1px solid #e5e6e8;
}

.header-inner {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 20px;
  height: 60px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
}

.site-brand {
  font-size: 20px;
  font-weight: 600;
  flex-shrink: 0;
}

.site-brand a {
  color: #222222;
}

.site-brand a:hover {
  text-decoration: none;
}

.site-nav .nav-list {
  display: flex;
  gap: 4px;
}

.site-nav .nav-list li a {
  display: block;
  padding: 6px 14px;
  font-size: 14px;
  color: #222222;
  border-radius: 4px;
  line-height: 1.4;
}

.site-nav .nav-list li a:hover {
  background: #f0f2f5;
  text-decoration: none;
}

.site-nav .nav-list li a.is-current {
  color: #1f6feb;
  background: #eef4fe;
  font-weight: 600;
}

.nav-toggle {
  display: none;
  width: 44px;
  height: 44px;
  align-items: center;
  justify-content: center;
  background: transparent;
  border: 1px solid #e5e6e8;
  border-radius: 6px;
  cursor: pointer;
  padding: 0;
  flex-shrink: 0;
}

.nav-toggle-icon {
  display: block;
  width: 18px;
  height: 2px;
  background: #222222;
  position: relative;
}

.nav-toggle-icon::before,
.nav-toggle-icon::after {
  content: "";
  position: absolute;
  left: 0;
  width: 18px;
  height: 2px;
  background: #222222;
}

.nav-toggle-icon::before {
  top: -6px;
}

.nav-toggle-icon::after {
  top: 6px;
}

.site-main {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 20px;
}

.site-main.home-main {
  padding: 0 20px;
}

.site-main.inner-main {
  padding: 24px 20px 60px;
}

.site-footer {
  background: #ffffff;
  border-top: 1px solid #e5e6e8;
  margin-top: 40px;
}

.footer-inner {
  max-width: 1200px;
  margin: 0 auto;
  padding: 40px 20px 24px;
  display: grid;
  grid-template-columns: 1.2fr 1fr 1.4fr 1.4fr;
  gap: 32px;
}

.footer-title {
  font-size: 15px;
  color: #222222;
  margin-bottom: 12px;
}

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

.footer-col ul li a {
  font-size: 14px;
  color: #666666;
}

.footer-col ul li a:hover {
  color: #1f6feb;
}

.footer-brand p {
  font-size: 14px;
  color: #666666;
  line-height: 1.7;
}

.footer-bottom {
  border-top: 1px solid #e5e6e8;
  padding: 16px 20px;
  text-align: center;
}

.footer-bottom p {
  font-size: 13px;
  color: #888888;
  line-height: 1.6;
}

.footer-bottom .content-note {
  margin-top: 4px;
}

/* 面包屑 */
.breadcrumb {
  font-size: 13px;
  color: #888888;
  margin-bottom: 16px;
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 6px;
}

.breadcrumb a {
  color: #666666;
}

.breadcrumb a:hover {
  color: #1f6feb;
}

.breadcrumb-sep {
  color: #bbbbbb;
}

.breadcrumb-current {
  color: #222222;
}

/* 页面标题区 */
.page-header {
  margin-bottom: 28px;
  padding-bottom: 16px;
  border-bottom: 1px solid #e5e6e8;
}

.page-title {
  font-size: 28px;
  color: #222222;
  margin-bottom: 8px;
}

.page-description {
  font-size: 15px;
  color: #666666;
  max-width: 720px;
}

/* 通用 section 标题 */
.section-title {
  font-size: 18px;
  color: #222222;
  margin-bottom: 16px;
  padding-bottom: 8px;
  border-bottom: 2px solid #1f6feb;
  display: inline-block;
}

.section-desc,
.section-note,
.section-intro {
  font-size: 14px;
  color: #666666;
  margin-bottom: 16px;
}

/* 按钮 */
.btn {
  display: inline-block;
  padding: 10px 22px;
  font-size: 14px;
  font-weight: 600;
  border-radius: 6px;
  line-height: 1.5;
  cursor: pointer;
  text-align: center;
  border: 1px solid transparent;
}

.btn-primary {
  background: #1f6feb;
  color: #ffffff;
  border-color: #1f6feb;
}

.btn-primary:hover {
  background: #185abc;
  text-decoration: none;
}

.btn-secondary {
  background: #ffffff;
  color: #1f6feb;
  border-color: #1f6feb;
}

.btn-secondary:hover {
  background: #eef4fe;
  text-decoration: none;
}

/* ============================================================
   首页
   ============================================================ */
/* Hero 区 */
.hero-section {
  padding: 32px 0 8px;
}

.hero-layout {
  display: grid;
  grid-template-columns: 1.3fr 1fr;
  gap: 32px;
  align-items: center;
  margin-bottom: 28px;
}

.hero-copy h1 {
  font-size: 28px;
  margin-bottom: 12px;
}

.hero-tagline {
  font-size: 16px;
  color: #666666;
  margin-bottom: 20px;
  max-width: 520px;
}

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

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

.hero-media {
  background: #ffffff;
  border: 1px solid #e5e6e8;
  border-radius: 8px;
  overflow: hidden;
}

.hero-media img {
  width: 100%;
  height: 240px;
  object-fit: cover;
}

/* 时间线 */
.timeline-updates {
  background: #ffffff;
  border: 1px solid #e5e6e8;
  border-radius: 8px;
  padding: 20px;
  margin-bottom: 32px;
}

.timeline-updates .section-title {
  margin-bottom: 12px;
}

.timeline-list {
  display: grid;
  gap: 0;
}

.timeline-item {
  display: flex;
  align-items: baseline;
  gap: 16px;
  padding: 10px 0;
  border-bottom: 1px solid #f0f1f3;
}

.timeline-item:last-child {
  border-bottom: none;
}

.timeline-item time {
  font-size: 12px;
  color: #888888;
  flex-shrink: 0;
  width: 80px;
}

.timeline-item p {
  font-size: 14px;
  color: #333333;
}

.content-media-primary {
  margin: 0 0 32px;
}

.content-media-primary img {
  width: 100%;
  height: 200px;
  object-fit: cover;
  border-radius: 8px;
}

.content-media-primary figcaption {
  font-size: 13px;
  color: #888888;
  padding: 8px 0 0;
}

/* 频道标签 */
.quick-tags {
  margin-bottom: 32px;
}

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

.tag-item {
  display: inline-block;
  padding: 6px 16px;
  background: #ffffff;
  border: 1px solid #e5e6e8;
  border-radius: 20px;
  font-size: 14px;
  color: #333333;
}

.tag-item:hover {
  border-color: #1f6feb;
  color: #1f6feb;
  text-decoration: none;
}

/* 三栏门户 */
.portal-columns {
  display: grid;
  grid-template-columns: 1fr 1fr 1fr;
  gap: 20px;
  margin-bottom: 40px;
}

.portal-col {
  background: #ffffff;
  border: 1px solid #e5e6e8;
  border-radius: 8px;
  padding: 20px;
  min-width: 0;
}

.portal-col .section-title {
  margin-bottom: 14px;
}

.channel-mini-list li,
.playlist-pick-list li,
.guide-mini-list li {
  padding: 8px 0;
  border-bottom: 1px solid #f0f1f3;
}

.channel-mini-list li:last-child,
.playlist-pick-list li:last-child,
.guide-mini-list li:last-child {
  border-bottom: none;
}

.channel-mini-list li a,
.playlist-pick-list li a,
.guide-mini-list li a {
  font-size: 14px;
  color: #333333;
}

.channel-mini-list li a:hover,
.playlist-pick-list li a:hover,
.guide-mini-list li a:hover {
  color: #1f6feb;
}

.channel-mini-list li {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 8px;
}

.time-badge {
  font-size: 12px;
  color: #888888;
  flex-shrink: 0;
}

.item-desc {
  font-size: 13px;
  color: #888888;
  margin-top: 4px;
  line-height: 1.5;
}

.more-link {
  display: inline-block;
  margin-top: 14px;
  font-size: 13px;
  color: #1f6feb;
}

/* 数据报告 */
.data-report {
  background: #ffffff;
  border: 1px solid #e5e6e8;
  border-radius: 8px;
  padding: 24px;
  margin-bottom: 40px;
}

.report-layout {
  display: grid;
  grid-template-columns: 1.2fr 1fr;
  gap: 32px;
  align-items: start;
}

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

.report-table {
  width: 100%;
}

.report-table th,
.report-table td {
  padding: 10px 12px;
  border: 1px solid #e5e6e8;
  font-size: 14px;
  text-align: left;
}

.report-table th {
  background: #f8f9fa;
  font-weight: 600;
  color: #333333;
}

.report-table td {
  color: #444444;
}

.report-table tbody tr:hover {
  background: #f8f9fa;
}

.report-notes p {
  font-size: 14px;
  color: #444444;
  margin-bottom: 12px;
  line-height: 1.7;
}

.report-notes .source-note {
  font-size: 13px;
  color: #888888;
  margin-bottom: 0;
}

/* 双路径 */
.dual-path {
  margin-bottom: 40px;
}

.path-cards {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 20px;
}

.path-card {
  background: #ffffff;
  border: 1px solid #e5e6e8;
  border-radius: 8px;
  padding: 24px;
}

.path-card h3 {
  font-size: 16px;
  margin-bottom: 10px;
}

.path-card p {
  font-size: 14px;
  color: #666666;
  margin-bottom: 16px;
  line-height: 1.7;
}

/* 帮助与反馈 */
.help-feedback {
  margin-bottom: 40px;
}

.help-cards {
  display: grid;
  grid-template-columns: 1fr 1fr 1fr;
  gap: 20px;
}

.help-card {
  background: #ffffff;
  border: 1px solid #e5e6e8;
  border-radius: 8px;
  padding: 20px;
}

.help-card h3 {
  font-size: 15px;
  margin-bottom: 8px;
}

.help-card p {
  font-size: 14px;
  color: #666666;
  margin-bottom: 12px;
  line-height: 1.6;
}

.help-card a {
  font-size: 14px;
  color: #1f6feb;
}

/* ============================================================
   频道总览
   ============================================================ */
.channel-grid {
  margin-bottom: 40px;
}

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

.channel-card {
  background: #ffffff;
  border: 1px solid #e5e6e8;
  border-radius: 8px;
  padding: 16px;
  display: flex;
  flex-direction: column;
  min-width: 0;
}

.channel-card img {
  width: 100%;
  height: 160px;
  object-fit: cover;
  border-radius: 6px;
  margin-bottom: 12px;
}

.channel-card h3 {
  font-size: 16px;
  margin-bottom: 8px;
}

.channel-card p {
  font-size: 14px;
  color: #666666;
  margin-bottom: 12px;
  line-height: 1.6;
  flex-grow: 1;
}

.channel-card a {
  font-size: 14px;
  color: #1f6feb;
}

.comparison-table {
  margin-bottom: 40px;
}

.table-wrapper {
  overflow-x: auto;
  background: #ffffff;
  border: 1px solid #e5e6e8;
  border-radius: 8px;
}

.table-wrapper table {
  width: 100%;
  min-width: 640px;
}

.table-wrapper th,
.table-wrapper td {
  padding: 12px 14px;
  border: 1px solid #e5e6e8;
  font-size: 14px;
  text-align: left;
}

.table-wrapper th {
  background: #f8f9fa;
  font-weight: 600;
  color: #333333;
}

.table-wrapper td {
  color: #444444;
}

.table-wrapper tbody tr:hover {
  background: #f8f9fa;
}

.channel-dynamics {
  margin-bottom: 40px;
}

.dynamics-list {
  background: #ffffff;
  border: 1px solid #e5e6e8;
  border-radius: 8px;
  padding: 8px 20px;
}

.dynamics-list li {
  display: flex;
  align-items: baseline;
  gap: 16px;
  padding: 10px 0;
  border-bottom: 1px solid #f0f1f3;
}

.dynamics-list li:last-child {
  border-bottom: none;
}

.dynamics-list time {
  font-size: 12px;
  color: #888888;
  flex-shrink: 0;
  width: 90px;
}

.dynamics-list span {
  font-size: 14px;
  color: #333333;
}

/* 页面布局（主内容 + 侧栏） */
.page-layout {
  display: grid;
  grid-template-columns: 1fr 320px;
  gap: 24px;
  align-items: start;
  margin-bottom: 40px;
}

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

.aside-suggestions {
  background: #ffffff;
  border: 1px solid #e5e6e8;
  border-radius: 8px;
  padding: 20px;
}

.aside-title {
  font-size: 16px;
  margin-bottom: 14px;
  padding-bottom: 8px;
  border-bottom: 2px solid #1f6feb;
  display: inline-block;
}

.aside-suggestions ul li {
  padding: 8px 0;
  border-bottom: 1px solid #f0f1f3;
  font-size: 14px;
  color: #444444;
  line-height: 1.6;
}

.aside-suggestions ul li:last-child {
  border-bottom: none;
}

/* 关联链接 */
.related-links {
  margin-bottom: 40px;
}

.related-links-list {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.related-links-list a {
  display: inline-block;
  padding: 10px 20px;
  background: #ffffff;
  border: 1px solid #e5e6e8;
  border-radius: 6px;
  font-size: 14px;
  color: #333333;
}

.related-links-list a:hover {
  border-color: #1f6feb;
  color: #1f6feb;
  text-decoration: none;
}

/* ============================================================
   专题片单
   ============================================================ */
.playlist-grid {
  margin-bottom: 40px;
}

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

.playlist-card {
  background: #ffffff;
  border: 1px solid #e5e6e8;
  border-radius: 8px;
  padding: 16px;
  display: flex;
  flex-direction: column;
  min-width: 0;
}

.playlist-figure {
  margin-bottom: 12px;
}

.playlist-figure img {
  width: 100%;
  height: 150px;
  object-fit: cover;
  border-radius: 6px;
}

.playlist-card h3 {
  font-size: 16px;
  margin-bottom: 8px;
}

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

.tag-scene,
.tag-duration {
  display: inline-block;
  font-size: 12px;
  color: #666666;
  background: #f0f2f5;
  padding: 2px 8px;
  border-radius: 4px;
}

.playlist-desc {
  font-size: 14px;
  color: #666666;
  line-height: 1.6;
  margin-bottom: 12px;
  flex-grow: 1;
}

.card-link {
  font-size: 14px;
  color: #1f6feb;
}

.playlist-comparison {
  margin-bottom: 40px;
}

.comparison-table th {
  font-weight: 600;
}

.table-note {
  font-size: 13px;
  color: #888888;
  margin-top: 10px;
}

.playlist-dynamics {
  margin-bottom: 40px;
}

.dynamics-name {
  font-size: 14px;
  color: #333333;
}

/* 选择建议 */
.suggestion-list li {
  padding: 10px 0;
  border-bottom: 1px solid #f0f1f3;
}

.suggestion-list li:last-child {
  border-bottom: none;
}

.suggestion-list strong {
  display: block;
  font-size: 14px;
  color: #333333;
  margin-bottom: 4px;
}

.suggestion-list li {
  font-size: 13px;
  color: #666666;
  line-height: 1.6;
}

/* 关联内容 */
.related-links-label {
  font-size: 14px;
  color: #666666;
  margin-right: 8px;
}

.related-links-item {
  display: inline-block;
  padding: 8px 16px;
  background: #ffffff;
  border: 1px solid #e5e6e8;
  border-radius: 6px;
  font-size: 14px;
  color: #333333;
  margin-right: 8px;
}

.related-links-item:hover {
  border-color: #1f6feb;
  color: #1f6feb;
  text-decoration: none;
}

/* ============================================================
   观看指南
   ============================================================ */
.guide-steps {
  margin-bottom: 40px;
}

.steps-list {
  display: grid;
  gap: 16px;
}

.step-item {
  display: flex;
  gap: 16px;
  background: #ffffff;
  border: 1px solid #e5e6e8;
  border-radius: 8px;
  padding: 20px;
}

.step-number {
  width: 36px;
  height: 36px;
  border-radius: 50%;
  background: #1f6feb;
  color: #ffffff;
  font-size: 16px;
  font-weight: 600;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}

.step-content {
  min-width: 0;
}

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

.step-content p {
  font-size: 14px;
  color: #666666;
  line-height: 1.7;
}

.step-content a {
  font-size: 14px;
  color: #1f6feb;
}

.device-tips {
  margin-bottom: 40px;
}

.device-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 20px;
}

.device-card {
  background: #ffffff;
  border: 1px solid #e5e6e8;
  border-radius: 8px;
  padding: 16px;
  display: flex;
  gap: 16px;
}

.device-media {
  flex-shrink: 0;
  width: 160px;
}

.device-media img {
  width: 160px;
  height: 110px;
  object-fit: cover;
  border-radius: 6px;
}

.device-content {
  min-width: 0;
}

.device-content h3 {
  font-size: 15px;
  margin-bottom: 6px;
}

.device-content p {
  font-size: 14px;
  color: #666666;
  line-height: 1.6;
}

.entry-reminder {
  margin-bottom: 40px;
}

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

.reminder-list li {
  background: #ffffff;
  border: 1px solid #e5e6e8;
  border-radius: 8px;
  padding: 16px;
}

.reminder-list h3 {
  font-size: 15px;
  margin-bottom: 6px;
}

.reminder-list p {
  font-size: 14px;
  color: #666666;
  line-height: 1.6;
}

/* 关联页面 */
.aside-related {
  background: #ffffff;
  border: 1px solid #e5e6e8;
  border-radius: 8px;
  padding: 20px;
  margin-bottom: 40px;
}

.aside-related h2 {
  font-size: 16px;
  margin-bottom: 10px;
  padding-bottom: 8px;
  border-bottom: 2px solid #1f6feb;
  display: inline-block;
}

.aside-related p {
  font-size: 14px;
  color: #666666;
  margin-bottom: 12px;
}

.aside-links li {
  padding: 6px 0;
}

.aside-links li a {
  font-size: 14px;
  color: #1f6feb;
}

/* 返回目录 */
.back-to-catalog {
  margin-bottom: 40px;
  background: #ffffff;
  border: 1px solid #e5e6e8;
  border-radius: 8px;
  padding: 20px;
}

.back-to-catalog h2 {
  font-size: 16px;
  margin-bottom: 8px;
}

.back-to-catalog p {
  font-size: 14px;
  color: #666666;
  margin-bottom: 12px;
}

.catalog-links {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.catalog-link {
  display: inline-block;
  padding: 10px 20px;
  background: #f0f2f5;
  border-radius: 6px;
  font-size: 14px;
  color: #333333;
}

.catalog-link:hover {
  background: #eef4fe;
  color: #1f6feb;
  text-decoration: none;
}

/* ============================================================
   入口核验
   ============================================================ */
.check-dimensions {
  margin-bottom: 40px;
}

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

.dimension-card {
  background: #ffffff;
  border: 1px solid #e5e6e8;
  border-radius: 8px;
  padding: 20px;
}

.dimension-card h3 {
  font-size: 15px;
  margin-bottom: 8px;
}

.dimension-card p {
  font-size: 14px;
  color: #666666;
  line-height: 1.6;
}

.check-list {
  margin-bottom: 40px;
}

.check-table {
  width: 100%;
  min-width: 560px;
}

.check-table th,
.check-table td {
  padding: 12px 14px;
  border: 1px solid #e5e6e8;
  font-size: 14px;
  text-align: left;
}

.check-table th {
  background: #f8f9fa;
  font-weight: 600;
  color: #333333;
}

.check-table td {
  color: #444444;
}

.check-table tbody tr:hover {
  background: #f8f9fa;
}

.troubleshooting {
  margin-bottom: 40px;
}

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

.trouble-list li {
  background: #ffffff;
  border: 1px solid #e5e6e8;
  border-radius: 8px;
  padding: 20px;
}

.trouble-list h3 {
  font-size: 15px;
  margin-bottom: 8px;
}

.trouble-list p {
  font-size: 14px;
  color: #666666;
  line-height: 1.6;
}

/* 观看前小提示 */
.aside-notes {
  background: #ffffff;
  border: 1px solid #e5e6e8;
  border-radius: 8px;
  padding: 20px;
  margin-bottom: 40px;
}

.aside-notes h2 {
  font-size: 16px;
  margin-bottom: 12px;
  padding-bottom: 8px;
  border-bottom: 2px solid #1f6feb;
  display: inline-block;
}

.aside-notes ul li {
  padding: 8px 0;
  border-bottom: 1px solid #f0f1f3;
}

.aside-notes ul li:last-child {
  border-bottom: none;
}

.aside-notes strong {
  display: block;
  font-size: 14px;
  color: #333333;
  margin-bottom: 4px;
}

.aside-notes ul li {
  font-size: 13px;
  color: #666666;
  line-height: 1.6;
}

/* 返回指南 */
.back-to-guide {
  margin-bottom: 40px;
}

.back-to-guide h2 {
  font-size: 16px;
  margin-bottom: 8px;
}

.back-to-guide p {
  font-size: 14px;
  color: #666666;
  margin-bottom: 8px;
}

.check-illustration {
  margin-top: 20px;
}

.check-illustration img {
  width: 100%;
  height: 200px;
  object-fit: cover;
  border-radius: 8px;
}

.check-illustration figcaption {
  font-size: 13px;
  color: #888888;
  padding: 8px 0 0;
}

/* ============================================================
   帮助与反馈
   ============================================================ */
.faq-section {
  margin-bottom: 40px;
}

.faq-group {
  margin-bottom: 24px;
}

.faq-group-title {
  font-size: 16px;
  margin-bottom: 12px;
  padding-bottom: 6px;
  border-bottom: 1px solid #e5e6e8;
}

.faq-item {
  background: #ffffff;
  border: 1px solid #e5e6e8;
  border-radius: 6px;
  margin-bottom: 10px;
}

.faq-item summary {
  padding: 14px 16px;
  font-size: 15px;
  font-weight: 600;
  color: #333333;
  cursor: pointer;
  list-style: none;
  position: relative;
  padding-right: 40px;
}

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

.faq-item summary::after {
  content: "+";
  position: absolute;
  right: 16px;
  top: 50%;
  transform: translateY(-50%);
  font-size: 18px;
  color: #1f6feb;
}

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

.faq-item[open] summary {
  border-bottom: 1px solid #f0f1f3;
}

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

.faq-answer p {
  font-size: 14px;
  color: #555555;
  line-height: 1.7;
  margin-bottom: 8px;
}

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

/* 反馈指南 */
.feedback-guide {
  margin-bottom: 40px;
}

.feedback-steps {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
  margin-bottom: 20px;
}

.feedback-step {
  background: #ffffff;
  border: 1px solid #e5e6e8;
  border-radius: 8px;
  padding: 20px;
}

.feedback-step h3 {
  font-size: 15px;
  margin-bottom: 8px;
}

.feedback-step p {
  font-size: 14px;
  color: #666666;
  line-height: 1.6;
}

.feedback-media img {
  width: 100%;
  height: 180px;
  object-fit: cover;
  border-radius: 8px;
}

.feedback-media figcaption {
  font-size: 13px;
  color: #888888;
  padding: 8px 0 0;
}

/* 帮助导航 */
.help-navigation {
  margin-bottom: 40px;
}

.help-card-list {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
}

.help-card h3 {
  font-size: 15px;
  margin-bottom: 8px;
}

.help-card p {
  font-size: 14px;
  color: #666666;
  margin-bottom: 12px;
  line-height: 1.6;
}

.help-card a {
  font-size: 14px;
  color: #1f6feb;
}

/* 返回目录 */
.back-to-catalog p {
  font-size: 14px;
  color: #666666;
}

.back-to-catalog p a {
  display: inline-block;
  margin-right: 16px;
  padding: 8px 16px;
  background: #f0f2f5;
  border-radius: 6px;
  color: #333333;
  font-size: 14px;
}

.back-to-catalog p a:hover {
  background: #eef4fe;
  color: #1f6feb;
  text-decoration: none;
}

/* ============================================================
   404
   ============================================================ */
.error-main {
  min-height: 60vh;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 60px 20px;
}

.error-section {
  text-align: center;
  max-width: 560px;
  background: #ffffff;
  border: 1px solid #e5e6e8;
  border-radius: 8px;
  padding: 40px;
}

.error-code {
  font-size: 72px;
  font-weight: 700;
  color: #1f6feb;
  line-height: 1;
  margin-bottom: 16px;
}

.error-title {
  font-size: 24px;
  margin-bottom: 12px;
}

.error-desc {
  font-size: 15px;
  color: #666666;
  margin-bottom: 24px;
}

.error-actions {
  margin-bottom: 16px;
}

.error-help {
  font-size: 14px;
  color: #888888;
}

/* ============================================================
   响应式
   ============================================================ */
@media (max-width: 960px) {
  .footer-inner {
    grid-template-columns: 1fr 1fr;
  }

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

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

  .help-card-list {
    grid-template-columns: repeat(2, 1fr);
  }

  .device-grid {
    grid-template-columns: 1fr;
  }

  .device-card {
    flex-direction: column;
  }

  .device-media {
    width: 100%;
  }

  .device-media img {
    width: 100%;
    height: 140px;
  }
}

@media (max-width: 768px) {
  .header-inner {
    height: auto;
    min-height: 60px;
    padding: 8px 16px;
    flex-wrap: wrap;
    gap: 8px;
  }

  .nav-toggle {
    display: flex;
    order: 3;
  }

  .site-nav {
    order: 4;
    width: 100%;
  }

  .site-nav .nav-list {
    display: none;
    flex-direction: column;
    gap: 0;
    padding: 8px 0;
    border-top: 1px solid #e5e6e8;
    margin-top: 4px;
  }

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

  .site-nav .nav-list li a {
    padding: 12px 8px;
    border-radius: 4px;
  }

  .site-main {
    padding: 0 16px;
  }

  .site-main.home-main {
    padding: 0 16px;
  }

  .site-main.inner-main {
    padding: 16px 16px 48px;
  }

  .hero-layout {
    grid-template-columns: 1fr;
    gap: 20px;
  }

  .hero-media img {
    height: 200px;
  }

  .portal-columns {
    grid-template-columns: 1fr;
    gap: 16px;
  }

  .report-layout {
    grid-template-columns: 1fr;
    gap: 20px;
  }

  .path-cards {
    grid-template-columns: 1fr;
    gap: 16px;
  }

  .help-cards {
    grid-template-columns: 1fr;
    gap: 16px;
  }

  .channel-grid-list {
    grid-template-columns: 1fr;
  }

  .playlist-grid-items {
    grid-template-columns: 1fr;
  }

  .page-layout {
    grid-template-columns: 1fr;
    gap: 16px;
  }

  .reminder-list {
    grid-template-columns: 1fr;
    gap: 16px;
  }

  .dimension-grid {
    grid-template-columns: 1fr;
    gap: 16px;
  }

  .trouble-list {
    grid-template-columns: 1fr;
    gap: 16px;
  }

  .feedback-steps {
    grid-template-columns: 1fr;
    gap: 16px;
  }

  .help-card-list {
    grid-template-columns: 1fr;
    gap: 16px;
  }

  .footer-inner {
    grid-template-columns: 1fr;
    gap: 24px;
    padding: 32px 16px 20px;
  }

  .footer-bottom {
    padding: 14px 16px;
  }

  .timeline-item {
    flex-direction: column;
    gap: 2px;
  }

  .timeline-item time {
    width: auto;
  }

  .step-item {
    padding: 16px;
  }

  .step-number {
    width: 32px;
    height: 32px;
    font-size: 14px;
  }

  .error-section {
    padding: 24px;
  }

  .error-code {
    font-size: 56px;
  }

  .related-links-list {
    flex-direction: column;
  }

  .related-links-list a {
    text-align: center;
  }

  .catalog-links {
    flex-direction: column;
  }

  .catalog-link {
    text-align: center;
  }

  .check-table {
    min-width: 480px;
  }
}

@media (max-width: 390px) {
  .header-inner {
    padding: 8px 12px;
  }

  .site-brand {
    font-size: 18px;
  }

  .site-main {
    padding: 0 12px;
  }

  .site-main.home-main {
    padding: 0 12px;
  }

  .site-main.inner-main {
    padding: 12px 12px 40px;
  }

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

  .hero-actions .btn {
    text-align: center;
  }

  .hero-media img {
    height: 180px;
  }

  .content-media-primary img {
    height: 160px;
  }

  .tag-list {
    gap: 8px;
  }

  .tag-item {
    padding: 6px 12px;
    font-size: 13px;
  }

  .channel-card img {
    height: 140px;
  }

  .playlist-figure img {
    height: 130px;
  }

  .device-media img {
    height: 120px;
  }

  .feedback-media img {
    height: 140px;
  }

  .check-illustration img {
    height: 160px;
  }

  .table-wrapper table {
    min-width: 520px;
  }

  .check-table {
    min-width: 420px;
  }
}