/* ==========================================================================
   优视频 besteasylearn.com — 全站样式
   分组：base / layout / components / pages / responsive
   ========================================================================== */

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

:root {
  --ink: #0E1B24;
  --teal: #123A44;
  --paper: #F5F6F2;
  --card: #FFFFFF;
  --line: #C8CFC9;
  --muted: #5B6B70;
  --amber: #B4762A;
  --brick: #8C3A2E;
  --paper-deep: #EDEFE8;
  --radius: 2px;
  --wrap: 1180px;
  --pad: 24px;
  --serif: "Noto Serif SC", "Songti SC", "SimSun", Georgia, serif;
  --sans: -apple-system, BlinkMacSystemFont, "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", "Helvetica Neue", Arial, sans-serif;
  --mono: ui-monospace, SFMono-Regular, "SF Mono", Menlo, Consolas, "Liberation Mono", monospace;
}

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

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

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

h1,
h2,
h3,
h4 {
  margin: 0;
  font-family: var(--serif);
  font-weight: 600;
  line-height: 1.35;
  color: var(--ink);
}

p {
  margin: 0;
}

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

figure {
  margin: 0;
}

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

a {
  color: var(--teal);
  text-decoration: none;
  text-underline-offset: 3px;
}

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

button {
  font: inherit;
  color: inherit;
}

.mono {
  font-family: var(--mono);
  font-size: 0.92em;
  letter-spacing: 0;
}

/* --------------------------------------------------------------------------
   2. layout — 页头、主容器、内页骨架、页脚
   -------------------------------------------------------------------------- */

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

.header-inner {
  max-width: var(--wrap);
  margin: 0 auto;
  padding: 0 var(--pad);
  min-height: 68px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  position: relative;
}

.brand {
  font-family: var(--serif);
  font-size: 21px;
  font-weight: 600;
  color: var(--ink);
  white-space: nowrap;
  flex: 0 0 auto;
}

.brand:hover {
  text-decoration: none;
  color: var(--teal);
}

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

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

.nav-list li {
  display: block;
}

.nav-list a {
  display: block;
  padding: 8px 11px;
  font-size: 14.5px;
  color: var(--ink);
  border-bottom: 2px solid transparent;
  white-space: nowrap;
}

.nav-list a:hover {
  color: var(--teal);
  text-decoration: none;
  border-bottom-color: var(--line);
}

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

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

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

.nav-toggle:hover {
  background: var(--paper-deep);
}

.site-main {
  display: block;
}

.home-main,
.inner-main,
.error-main {
  max-width: var(--wrap);
  margin: 0 auto;
  padding: 0 var(--pad) 64px;
}

/* 内页统一外壳 */

.breadcrumb {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 8px;
  padding: 20px 0 0;
  font-size: 13px;
  color: var(--muted);
}

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

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

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

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

.page-header {
  padding: 14px 0 18px;
  border-bottom: 1px solid var(--line);
}

.page-title {
  font-size: clamp(26px, 3.4vw, 38px);
  font-weight: 600;
  color: var(--ink);
  max-width: 22em;
}

/* 页脚 */

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

.footer-top {
  max-width: var(--wrap);
  margin: 0 auto;
  padding: 40px var(--pad) 32px;
  display: grid;
  grid-template-columns: 1.2fr 1fr 1.4fr;
  gap: 40px;
}

.footer-title {
  font-size: 15px;
  font-weight: 600;
  color: var(--ink);
  margin-bottom: 14px;
}

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

.footer-links a {
  font-size: 14px;
  color: var(--muted);
}

.footer-links a:hover {
  color: var(--teal);
}

.footer-col:last-child p {
  font-size: 14px;
  color: var(--muted);
  line-height: 1.8;
}

.footer-col:last-child p + p {
  margin-top: 8px;
}

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

.footer-bottom {
  max-width: var(--wrap);
  margin: 0 auto;
  padding: 18px var(--pad) 28px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 10px;
}

.footer-brand {
  font-size: 13px;
  color: var(--muted);
}

.footer-bottom-links {
  display: flex;
  gap: 18px;
}

.footer-bottom-links a {
  font-size: 13px;
  color: var(--muted);
}

.footer-bottom-links a:hover {
  color: var(--teal);
}

/* --------------------------------------------------------------------------
   3. components — 通用按钮、表格、状态、注释、折叠、步骤、链接组、图片
   -------------------------------------------------------------------------- */

/* 按钮 */

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 44px;
  padding: 10px 22px;
  font-size: 15px;
  font-weight: 600;
  border-radius: var(--radius);
  border: 1px solid var(--teal);
  transition: background-color 0.15s ease, color 0.15s ease;
}

.btn:hover {
  text-decoration: none;
}

.btn-primary {
  background: var(--teal);
  color: #FFFFFF;
}

.btn-primary:hover {
  background: var(--ink);
  border-color: var(--ink);
  color: #FFFFFF;
}

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

.btn-ghost:hover {
  background: var(--paper-deep);
  color: var(--teal);
}

/* 文本链接 */

.text-link {
  display: inline-block;
  font-size: 14px;
  color: var(--teal);
  border-bottom: 1px solid var(--teal);
  padding-bottom: 1px;
}

.text-link:hover {
  text-decoration: none;
  color: var(--ink);
  border-bottom-color: var(--ink);
}

/* 表格 */

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

.data-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 14px;
  line-height: 1.5;
}

.data-table caption,
.table-caption {
  caption-side: top;
  text-align: left;
  padding: 12px 16px;
  font-size: 13px;
  color: var(--muted);
  border-bottom: 1px solid var(--line);
}

.data-table thead th {
  padding: 12px 16px;
  text-align: left;
  font-family: var(--sans);
  font-weight: 600;
  font-size: 13px;
  color: var(--ink);
  border-bottom: 1px solid var(--ink);
  white-space: nowrap;
}

.data-table tbody th {
  padding: 12px 16px;
  text-align: left;
  font-family: var(--sans);
  font-weight: 400;
  color: var(--ink);
  border-bottom: 1px solid var(--line);
  vertical-align: top;
}

.data-table tbody td {
  padding: 12px 16px;
  color: var(--muted);
  border-bottom: 1px solid var(--line);
  vertical-align: top;
}

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

.data-table tbody tr:hover th,
.data-table tbody tr:hover td {
  background: var(--paper-deep);
}

.data-table th.row-strong {
  font-weight: 600;
  color: var(--teal);
}

.table-note {
  margin-top: 10px;
  font-size: 13px;
  line-height: 1.65;
  color: var(--muted);
}

/* 状态标签 */

.status {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 46px;
  padding: 2px 8px;
  font-size: 12px;
  line-height: 1.5;
  border-radius: var(--radius);
  border: 1px solid currentColor;
  white-space: nowrap;
  flex: 0 0 auto;
}

.status-ok {
  color: var(--teal);
}

.status-tip {
  color: var(--amber);
}

.status-warn {
  color: var(--amber);
}

.status-risk {
  color: var(--brick);
}

.status-note {
  color: var(--muted);
}

/* 注释块 */

.note-block {
  border-left: 2px solid var(--line);
  padding: 4px 0 4px 16px;
  font-size: 13px;
  line-height: 1.7;
  color: var(--muted);
}

.note-block p + p {
  margin-top: 8px;
}

.note-block h3 {
  font-size: 15px;
  font-family: var(--sans);
  font-weight: 600;
  color: var(--ink);
  margin-bottom: 6px;
}

/* 折叠问答 */

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

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

.faq-item summary {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 16px 4px;
  font-size: 16px;
  font-weight: 600;
  color: var(--ink);
  cursor: pointer;
  list-style: none;
}

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

.faq-item summary::after {
  content: "+";
  flex: 0 0 auto;
  font-family: var(--mono);
  font-size: 18px;
  color: var(--teal);
}

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

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

.faq-item p,
.faq-answer p {
  padding: 0 4px 18px;
  font-size: 15px;
  color: var(--muted);
  max-width: 68em;
}

.faq-answer p {
  padding-top: 0;
}

/* 编号步骤列表 */

.step-list {
  counter-reset: step;
  display: grid;
  gap: 18px;
}

.step-item {
  counter-increment: step;
  position: relative;
  padding-left: 46px;
  min-height: 34px;
}

.step-item::before {
  content: counter(step);
  position: absolute;
  left: 0;
  top: 0;
  width: 32px;
  height: 32px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: var(--mono);
  font-size: 14px;
  color: var(--teal);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--card);
}

.step-item h3 {
  font-size: 16px;
  font-family: var(--sans);
  font-weight: 600;
  margin-bottom: 4px;
}

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

/* 相关链接组（首页 / 专题页横条） */

.related-links {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 10px 18px;
  margin-top: 40px;
  padding-top: 18px;
  border-top: 1px solid var(--line);
  font-size: 14px;
}

.related-links-label {
  color: var(--muted);
  font-size: 13px;
}

.related-links-item {
  color: var(--teal);
  border-bottom: 1px solid var(--line);
}

.related-links-item:hover {
  border-bottom-color: var(--teal);
  text-decoration: none;
}

/* 相关入口组（内页列表） */

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

.related-list a {
  display: flex;
  align-items: center;
  min-height: 44px;
  padding: 10px 16px;
  font-size: 14px;
  color: var(--teal);
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.related-list a:hover {
  text-decoration: none;
  background: var(--paper-deep);
  border-color: var(--teal);
}

/* 图片容器 */

.hero-figure,
.topic-media,
.flow-media figure,
.group-media,
.topic-feature-media,
.media-figure,
.access-figure,
.updates-figure {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
}

.hero-figure img,
.topic-media img,
.flow-media img,
.group-media img,
.topic-feature-media img,
.media-figure img,
.access-figure img,
.updates-figure img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 16 / 10;
  object-fit: cover;
}

.hero-figure figcaption,
.topic-media figcaption,
.flow-media figcaption,
.group-media figcaption,
.topic-feature-media figcaption,
.media-figure figcaption,
.access-figure figcaption,
.updates-figure figcaption {
  padding: 10px 14px;
  font-size: 13px;
  line-height: 1.65;
  color: var(--muted);
  border-top: 1px solid var(--line);
}

/* 内页底部页面地址行 */

.page-url,
.page-url-line {
  margin-top: 32px;
  padding-top: 14px;
  border-top: 1px solid var(--line);
  font-size: 13px;
  color: var(--muted);
  overflow-wrap: anywhere;
}

.page-url a,
.page-url-line a {
  font-family: var(--mono);
  font-size: 12.5px;
  color: var(--muted);
}

.page-url a:hover,
.page-url-line a:hover {
  color: var(--teal);
}

/* 内页通用区块 */

.section-title {
  font-size: 22px;
  margin-bottom: 12px;
}

.section-intro {
  font-size: 15px;
  color: var(--muted);
  max-width: 62em;
  margin-bottom: 18px;
}

.section-note {
  font-size: 15px;
  color: var(--muted);
  max-width: 62em;
  margin-bottom: 18px;
}

/* --------------------------------------------------------------------------
   4. pages — 各页业务模块
   -------------------------------------------------------------------------- */

/* ---------- 首页 ---------- */

.anchor-bar {
  padding: 14px 0 0;
  border-bottom: 1px solid var(--line);
  overflow-x: auto;
}

.anchor-list {
  display: flex;
  gap: 4px;
  min-width: max-content;
}

.anchor-list a {
  display: block;
  padding: 6px 12px 12px;
  font-size: 13.5px;
  color: var(--muted);
  border-bottom: 2px solid transparent;
  white-space: nowrap;
}

.anchor-list a:hover {
  color: var(--teal);
  text-decoration: none;
  border-bottom-color: var(--line);
}

/* 首页首屏 */

.hero-portal {
  display: grid;
  grid-template-columns: minmax(0, 1.9fr) minmax(0, 1fr);
  gap: 40px;
  padding: 36px 0 44px;
  border-bottom: 1px solid var(--line);
}

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

.hero-kicker {
  font-size: 13px;
  color: var(--amber);
  margin-bottom: 12px;
}

.hero-title {
  font-size: clamp(28px, 3.6vw, 42px);
  font-weight: 600;
  color: var(--ink);
  margin-bottom: 16px;
  max-width: 18em;
}

.hero-lead {
  font-size: 16px;
  line-height: 1.8;
  color: var(--muted);
  max-width: 44em;
  margin-bottom: 22px;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-bottom: 26px;
}

.hero-figure {
  margin-top: 4px;
}

.hero-side {
  display: flex;
  flex-direction: column;
  gap: 20px;
  min-width: 0;
}

.side-panel {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 18px;
}

.panel-title {
  font-size: 16px;
  font-family: var(--sans);
  font-weight: 600;
  color: var(--ink);
  margin-bottom: 12px;
  padding-bottom: 10px;
  border-bottom: 1px solid var(--line);
}

.channel-tags {
  display: flex;
  flex-direction: column;
  gap: 2px;
}

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

.channel-tags li:last-child {
  border-bottom: 0;
}

.channel-tags a {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 10px;
  min-height: 40px;
  padding: 8px 2px;
  font-size: 14px;
  color: var(--ink);
}

.channel-tags a:hover {
  color: var(--teal);
  text-decoration: none;
}

.tag-name {
  min-width: 0;
}

.tag-count {
  flex: 0 0 auto;
  font-family: var(--mono);
  font-size: 12px;
  color: var(--muted);
}

.panel-link {
  display: inline-block;
  margin-top: 12px;
  font-size: 13px;
  color: var(--teal);
}

.recent-list {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.recent-list li {
  display: flex;
  gap: 10px;
  align-items: baseline;
  font-size: 13.5px;
  color: var(--muted);
  padding-bottom: 10px;
  border-bottom: 1px solid var(--line);
}

.recent-list li:last-child {
  border-bottom: 0;
  padding-bottom: 0;
}

.batch-no {
  flex: 0 0 auto;
  font-family: var(--mono);
  font-size: 12px;
  color: var(--teal);
}

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

/* 首页区块通用 */

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

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

.section-head h2 {
  font-size: 22px;
  margin-bottom: 8px;
}

.section-lead {
  font-size: 15px;
  color: var(--muted);
  max-width: 62em;
}

/* 频道权重总览 */

.section-table .data-table thead th:last-child,
.section-table .data-table tbody td:last-child {
  white-space: nowrap;
}

/* 专题片单交错块 */

.section-topics .topic-block {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
  gap: 32px;
  align-items: center;
  padding: 26px 0;
  border-top: 1px solid var(--line);
}

.section-topics .topic-block:first-of-type {
  border-top: 0;
  padding-top: 0;
}

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

.topic-tag {
  display: inline-block;
  font-size: 12px;
  color: var(--teal);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 1px 8px;
  margin-bottom: 10px;
}

.topic-title {
  font-size: 19px;
  margin-bottom: 10px;
}

.topic-desc {
  font-size: 15px;
  color: var(--muted);
  margin-bottom: 12px;
}

.topic-order {
  font-size: 13px;
  color: var(--muted);
  border-left: 2px solid var(--line);
  padding-left: 12px;
}

.section-topics .topic-block-reverse .topic-text {
  order: 2;
}

.section-topics .topic-block-reverse .topic-media {
  order: 1;
}

/* 观看前核验清单 */

.section-precheck {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1.7fr);
  gap: 40px;
  align-items: start;
}

.precheck-intro h2 {
  font-size: 22px;
  margin-bottom: 10px;
}

.precheck-intro p {
  font-size: 15px;
  color: var(--muted);
  margin-bottom: 14px;
}

.precheck-list {
  display: flex;
  flex-direction: column;
  gap: 2px;
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.precheck-list li {
  display: flex;
  align-items: flex-start;
  gap: 14px;
  padding: 14px 18px;
  border-bottom: 1px solid var(--line);
}

.precheck-list li:last-child {
  border-bottom: 0;
}

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

.precheck-body h3 {
  font-size: 15px;
  font-family: var(--sans);
  font-weight: 600;
  margin-bottom: 2px;
}

.precheck-body p {
  font-size: 14px;
  color: var(--muted);
}

/* 观看流程 */

.section-flow {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1.15fr);
  gap: 40px;
  align-items: start;
}

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

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

.flow-body h2 {
  font-size: 22px;
  margin-bottom: 8px;
}

.flow-body .section-lead {
  margin-bottom: 20px;
}

/* 近期编排动态 */

.section-updates .text-link {
  margin-top: 14px;
}

/* 常见问题 */

.section-faq .faq-item summary {
  font-size: 16px;
}

/* 反馈入口条 */

.section-cta {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 20px;
  padding: 32px 0;
  border-bottom: 1px solid var(--line);
}

.cta-body {
  flex: 1 1 380px;
  min-width: 0;
}

.cta-body h2 {
  font-size: 20px;
  margin-bottom: 6px;
}

.cta-body p {
  font-size: 15px;
  color: var(--muted);
}

.cta-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  flex: 0 0 auto;
}

/* ---------- 频道总览 ---------- */

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

.page-tag,
.page-label {
  display: inline-block;
  font-size: 12px;
  color: var(--teal);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 1px 8px;
  margin-bottom: 12px;
}

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

.page-meta {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px 14px;
  margin-top: 12px;
  font-size: 13px;
  color: var(--muted);
}

.page-meta .mono {
  font-size: 12.5px;
  color: var(--teal);
}

.channel-index {
  padding: 26px 0 8px;
}

.anchor-row {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.anchor-row a {
  display: inline-flex;
  align-items: center;
  min-height: 36px;
  padding: 6px 12px;
  font-size: 13.5px;
  color: var(--teal);
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.anchor-row a:hover {
  text-decoration: none;
  border-color: var(--teal);
  background: var(--paper-deep);
}

.channel-group {
  padding: 30px 0;
  border-bottom: 1px solid var(--line);
}

.group-note {
  font-size: 15px;
  color: var(--muted);
  max-width: 62em;
  margin-bottom: 18px;
}

.group-media {
  margin-bottom: 18px;
  max-width: 720px;
}

.audience-map {
  padding: 30px 0;
  border-bottom: 1px solid var(--line);
}

.audience-map .data-table tbody th {
  white-space: nowrap;
}

.related-links h2 {
  font-size: 18px;
  margin-bottom: 14px;
}

/* ---------- 专题片单 ---------- */

.page-hero {
  padding: 18px 0 24px;
  border-bottom: 1px solid var(--line);
}

.section-tag {
  display: inline-block;
  font-size: 12px;
  color: var(--teal);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 1px 8px;
  margin-bottom: 12px;
}

.page-hero .page-lead,
.section-tag + .page-lead {
  margin-bottom: 14px;
}

.meta-line {
  display: flex;
  flex-wrap: wrap;
  gap: 10px 28px;
  margin: 0;
}

.meta-item {
  display: flex;
  align-items: baseline;
  gap: 8px;
  font-size: 13px;
}

.meta-item dt {
  color: var(--muted);
}

.meta-item dd {
  margin: 0;
  color: var(--ink);
  font-family: var(--mono);
  font-size: 12.5px;
}

.topic-feature {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1.1fr);
  gap: 36px;
  align-items: center;
  padding: 36px 0;
  border-bottom: 1px solid var(--line);
}

.topic-feature-text {
  min-width: 0;
}

.topic-feature-text h2 {
  font-size: 24px;
  margin-bottom: 12px;
}

.topic-feature-text p {
  font-size: 15px;
  color: var(--muted);
}

.topic-feature-media {
  min-width: 0;
}

.topic-parts {
  padding: 36px 0;
  border-bottom: 1px solid var(--line);
}

.topic-parts h2,
.topic-secondary h2,
.topic-rules h2 {
  font-size: 22px;
  margin-bottom: 8px;
}

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

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

.topic-part h3 {
  font-size: 16px;
  font-family: var(--sans);
  font-weight: 600;
  margin-bottom: 8px;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--line);
}

.topic-part p {
  font-size: 14.5px;
  color: var(--muted);
}

.topic-secondary {
  padding: 36px 0;
  border-bottom: 1px solid var(--line);
}

.topic-rules {
  padding: 36px 0;
  border-bottom: 1px solid var(--line);
}

.rule-list {
  display: grid;
  gap: 16px;
  margin-top: 20px;
}

.rule-item {
  padding-left: 16px;
  border-left: 2px solid var(--line);
  min-width: 0;
}

.rule-item h3 {
  font-size: 16px;
  font-family: var(--sans);
  font-weight: 600;
  margin-bottom: 4px;
}

.rule-item p {
  font-size: 14.5px;
  color: var(--muted);
  max-width: 62em;
}

/* ---------- 观看指南 ---------- */

.page-intro {
  padding: 18px 0 24px;
  border-bottom: 1px solid var(--line);
}

.page-intro .page-lead {
  margin-bottom: 12px;
}

.page-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 300px;
  gap: 40px;
  align-items: start;
  padding-top: 32px;
}

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

.side-column {
  min-width: 0;
}

.section-block {
  margin-bottom: 36px;
}

.section-block h2 {
  font-size: 22px;
  margin-bottom: 8px;
}

.section-block > .table-wrap {
  margin-top: 4px;
}

.section-block .note-block {
  margin-top: 14px;
}

.side-card {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 20px;
}

.side-card-title {
  font-size: 16px;
  font-family: var(--sans);
  font-weight: 600;
  margin-bottom: 14px;
  padding-bottom: 10px;
  border-bottom: 1px solid var(--line);
}

.quick-list {
  display: flex;
  flex-direction: column;
  gap: 14px;
}

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

.quick-title {
  font-size: 14px;
  font-family: var(--sans);
  font-weight: 600;
  color: var(--teal);
  margin-bottom: 2px;
}

.quick-item p {
  font-size: 13.5px;
  line-height: 1.65;
  color: var(--muted);
}

.media-figure {
  margin: 0 0 36px;
}

.related-nav {
  padding: 28px 0 0;
  border-top: 1px solid var(--line);
}

.related-title {
  font-size: 18px;
  margin-bottom: 14px;
}

/* ---------- 入口核验 ---------- */

.page-title-block {
  padding: 18px 0 24px;
  border-bottom: 1px solid var(--line);
}

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

.access-steps {
  padding: 32px 0;
  border-bottom: 1px solid var(--line);
}

.access-steps h2 {
  font-size: 22px;
  margin-bottom: 8px;
}

.steps-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 16px;
  margin-top: 20px;
}

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

.step-num {
  display: inline-block;
  font-size: 13px;
  color: var(--teal);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 0 6px;
  margin-bottom: 10px;
}

.step-card h3 {
  font-size: 15px;
  font-family: var(--sans);
  font-weight: 600;
  margin-bottom: 6px;
}

.step-card p {
  font-size: 14px;
  color: var(--muted);
}

.access-figure {
  margin: 0 0 32px;
}

.access-table-section {
  padding: 32px 0;
  border-bottom: 1px solid var(--line);
}

.access-table-section h2 {
  font-size: 22px;
  margin-bottom: 8px;
}

.access-table-section .data-table td:first-child {
  color: var(--ink);
}

.access-table-section .status {
  margin-right: 6px;
}

.access-boundary {
  padding: 32px 0;
  border-bottom: 1px solid var(--line);
}

.access-boundary h2 {
  font-size: 20px;
  margin-bottom: 12px;
}

/* ---------- 更新说明 ---------- */

.updates-principles {
  padding: 32px 0;
  border-bottom: 1px solid var(--line);
}

.updates-principles h2 {
  font-size: 22px;
  margin-bottom: 8px;
}

.principle-list {
  display: grid;
  gap: 16px;
  margin-top: 20px;
}

.principle-item {
  padding-left: 16px;
  border-left: 2px solid var(--line);
  min-width: 0;
}

.principle-item h3 {
  font-size: 16px;
  font-family: var(--sans);
  font-weight: 600;
  margin-bottom: 4px;
}

.principle-item p {
  font-size: 14.5px;
  color: var(--muted);
  max-width: 62em;
}

.updates-figure {
  margin: 0 0 32px;
}

.updates-batches {
  padding: 32px 0;
  border-bottom: 1px solid var(--line);
}

.updates-batches h2 {
  font-size: 22px;
  margin-bottom: 8px;
}

.updates-notes {
  padding: 32px 0;
  border-bottom: 1px solid var(--line);
}

.updates-notes h2 {
  font-size: 20px;
  margin-bottom: 16px;
}

.updates-notes .note-block + .note-block {
  margin-top: 18px;
}

/* ---------- 问题反馈 ---------- */

.feedback-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 32px;
  padding: 32px 0;
  border-bottom: 1px solid var(--line);
}

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

.feedback-col h2 {
  font-size: 20px;
  margin-bottom: 8px;
}

.feedback-item {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 16px 18px;
  margin-top: 12px;
  min-width: 0;
}

.feedback-item h3 {
  font-size: 15px;
  font-family: var(--sans);
  font-weight: 600;
  margin-bottom: 4px;
}

.feedback-item p {
  font-size: 14px;
  color: var(--muted);
}

.feedback-flow {
  padding: 32px 0;
  border-bottom: 1px solid var(--line);
}

.feedback-flow h2 {
  font-size: 22px;
  margin-bottom: 8px;
}

.feedback-flow .step-list {
  margin-top: 20px;
}

.flow-link {
  margin-top: 18px;
  font-size: 14px;
}

.flow-link a {
  color: var(--teal);
  border-bottom: 1px solid var(--teal);
}

.flow-link a:hover {
  text-decoration: none;
  color: var(--ink);
  border-bottom-color: var(--ink);
}

.feedback-boundary {
  padding: 32px 0;
  border-bottom: 1px solid var(--line);
}

.feedback-boundary h2 {
  font-size: 20px;
  margin-bottom: 12px;
}

.feedback-grid + .feedback-flow {
  border-bottom: 1px solid var(--line);
}

/* ---------- 404 ---------- */

.error-main {
  padding-top: 56px;
}

.error-panel {
  max-width: 640px;
}

.error-code {
  font-family: var(--mono);
  font-size: 14px;
  color: var(--amber);
  margin-bottom: 10px;
}

.error-panel h1 {
  font-size: clamp(26px, 3.4vw, 38px);
  margin-bottom: 14px;
}

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

.error-hints {
  display: grid;
  gap: 8px;
  margin-bottom: 26px;
}

.error-hints li {
  position: relative;
  padding-left: 18px;
  font-size: 15px;
  color: var(--muted);
}

.error-hints li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.72em;
  width: 6px;
  height: 6px;
  background: var(--line);
  border-radius: 1px;
}

.error-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-bottom: 44px;
}

.error-links {
  padding-top: 28px;
  border-top: 1px solid var(--line);
}

.error-links h2 {
  font-size: 18px;
  margin-bottom: 14px;
}

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

.error-link-list a {
  display: flex;
  align-items: center;
  min-height: 44px;
  padding: 10px 16px;
  font-size: 14px;
  color: var(--teal);
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.error-link-list a:hover {
  text-decoration: none;
  background: var(--paper-deep);
  border-color: var(--teal);
}

/* --------------------------------------------------------------------------
   5. responsive — 1080px / 720px / 480px
   -------------------------------------------------------------------------- */

@media (max-width: 1080px) {
  .hero-portal {
    grid-template-columns: minmax(0, 1.6fr) minmax(0, 1fr);
    gap: 28px;
  }

  .section-precheck,
  .section-flow,
  .topic-feature {
    gap: 28px;
  }

  .page-layout {
    grid-template-columns: minmax(0, 1fr) 260px;
    gap: 28px;
  }

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

  .footer-top {
    grid-template-columns: 1fr 1fr 1.2fr;
    gap: 28px;
  }
}

@media (max-width: 900px) {
  .nav-list a {
    padding: 8px 8px;
    font-size: 14px;
  }

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

  .hero-side {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 16px;
  }

  .section-precheck,
  .section-flow,
  .topic-feature {
    grid-template-columns: minmax(0, 1fr);
  }

  .section-flow .flow-media {
    order: 2;
  }

  .section-flow .flow-body {
    order: 1;
  }

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

  .side-column {
    order: 2;
  }

  .content-column {
    order: 1;
  }
}

@media (max-width: 720px) {
  :root {
    --pad: 16px;
  }

  body {
    font-size: 15px;
  }

  .header-inner {
    min-height: 60px;
    gap: 12px;
  }

  .brand {
    font-size: 19px;
  }

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

  .site-nav {
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    z-index: 30;
    display: block;
    background: var(--card);
    border-bottom: 1px solid var(--line);
    padding: 8px var(--pad) 14px;
    box-shadow: 0 6px 0 rgba(14, 27, 36, 0.04);
  }

  .nav-list {
    display: none;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    width: 100%;
  }

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

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

  .nav-list li:last-child {
    border-bottom: 0;
  }

  .nav-list a {
    display: flex;
    align-items: center;
    min-height: 44px;
    padding: 10px 4px;
    font-size: 15px;
    border-bottom: 0;
  }

  .nav-list a.is-current {
    color: var(--teal);
    border-bottom: 0;
  }

  .home-main,
  .inner-main,
  .error-main {
    padding-bottom: 44px;
  }

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

  .breadcrumb {
    padding-top: 16px;
    font-size: 12.5px;
  }

  .page-header {
    padding: 12px 0 14px;
  }

  .anchor-bar {
    padding-top: 10px;
  }

  .anchor-list a {
    padding: 6px 10px 10px;
    font-size: 13px;
  }

  .hero-portal {
    padding: 24px 0 32px;
    gap: 24px;
  }

  .hero-title {
    font-size: 24px;
    max-width: none;
  }

  .hero-lead {
    font-size: 15px;
  }

  .hero-actions {
    gap: 10px;
    margin-bottom: 20px;
  }

  .hero-actions .btn {
    flex: 1 1 140px;
  }

  .hero-side {
    grid-template-columns: minmax(0, 1fr);
    gap: 14px;
  }

  .section {
    padding: 30px 0;
  }

  .section-head h2,
  .precheck-intro h2,
  .flow-body h2,
  .topic-parts h2,
  .topic-secondary h2,
  .topic-rules h2,
  .access-steps h2,
  .access-table-section h2,
  .updates-principles h2,
  .updates-batches h2,
  .feedback-flow h2,
  .section-block h2,
  .section-title {
    font-size: 19px;
  }

  .section-topics .topic-block {
    grid-template-columns: minmax(0, 1fr);
    gap: 16px;
    padding: 22px 0;
  }

  .section-topics .topic-block-reverse .topic-text,
  .section-topics .topic-block-reverse .topic-media {
    order: 0;
  }

  .topic-title {
    font-size: 17px;
  }

  .topic-desc,
  .topic-order {
    font-size: 14px;
  }

  .section-precheck {
    gap: 20px;
  }

  .precheck-list li {
    padding: 12px 14px;
    gap: 10px;
  }

  .section-flow {
    gap: 22px;
  }

  .section-flow .flow-media {
    order: 2;
  }

  .section-flow .flow-body {
    order: 1;
  }

  .section-cta {
    flex-direction: column;
    align-items: flex-start;
    gap: 16px;
    padding: 24px 0;
  }

  .cta-actions {
    width: 100%;
  }

  .cta-actions .btn {
    flex: 1 1 140px;
  }

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

  .related-links {
    gap: 8px 14px;
    margin-top: 28px;
  }

  /* 表格转标签行 */

  .table-wrap {
    overflow-x: visible;
    border: 0;
    background: transparent;
  }

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

  .data-table thead {
    display: none;
  }

  .data-table caption,
  .table-caption {
    display: block;
    padding: 0 0 10px;
    border-bottom: 0;
  }

  .data-table tbody tr {
    background: var(--card);
    border: 1px solid var(--line);
    border-radius: var(--radius);
    margin-bottom: 12px;
    padding: 4px 0;
  }

  .data-table tbody tr:last-child {
    margin-bottom: 0;
  }

  .data-table tbody th {
    font-weight: 600;
    color: var(--ink);
    border-bottom: 1px solid var(--line);
    padding: 10px 14px;
  }

  .data-table tbody td {
    display: flex;
    align-items: flex-start;
    gap: 10px;
    padding: 8px 14px;
    border-bottom: 1px dashed var(--line);
    line-height: 1.6;
  }

  .data-table tbody td::before {
    content: attr(data-label);
    flex: 0 0 84px;
    font-size: 12.5px;
    color: var(--muted);
  }

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

  .data-table tbody tr:hover th,
  .data-table tbody tr:hover td {
    background: transparent;
  }

  .table-note {
    margin-top: 8px;
  }

  /* 内页模块 */

  .page-head,
  .page-hero,
  .page-intro,
  .page-title-block {
    padding: 14px 0 18px;
  }

  .page-lead {
    font-size: 15px;
  }

  .channel-index {
    padding: 20px 0 4px;
  }

  .anchor-row {
    flex-wrap: nowrap;
    overflow-x: auto;
    padding-bottom: 6px;
  }

  .anchor-row li {
    flex: 0 0 auto;
  }

  .anchor-row a {
    white-space: nowrap;
  }

  .channel-group,
  .audience-map,
  .topic-parts,
  .topic-secondary,
  .topic-rules,
  .access-steps,
  .access-table-section,
  .access-boundary,
  .updates-principles,
  .updates-batches,
  .updates-notes,
  .feedback-flow,
  .feedback-boundary {
    padding: 24px 0;
  }

  .topic-feature {
    padding: 24px 0;
    gap: 18px;
  }

  .topic-feature-text h2 {
    font-size: 20px;
  }

  .topic-parts-grid {
    grid-template-columns: minmax(0, 1fr);
    gap: 12px;
    margin-top: 16px;
  }

  .topic-part {
    padding: 16px;
  }

  .page-layout {
    padding-top: 24px;
    gap: 24px;
  }

  .section-block {
    margin-bottom: 28px;
  }

  .side-card {
    padding: 16px;
  }

  .steps-grid {
    grid-template-columns: minmax(0, 1fr);
    gap: 12px;
    margin-top: 16px;
  }

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

  .feedback-item {
    padding: 14px;
    margin-top: 10px;
  }

  .step-item {
    padding-left: 42px;
  }

  .step-item h3 {
    font-size: 15px;
  }

  .step-item p {
    font-size: 14px;
  }

  .faq-item summary {
    padding: 14px 2px;
    font-size: 15px;
    gap: 12px;
  }

  .faq-item p,
  .faq-answer p {
    font-size: 14px;
    padding-bottom: 16px;
  }

  .media-figure,
  .access-figure,
  .updates-figure {
    margin-bottom: 24px;
  }

  .related-nav {
    padding-top: 22px;
  }

  .error-main {
    padding-top: 36px;
  }

  .error-actions {
    margin-bottom: 32px;
  }

  .footer-top {
    grid-template-columns: minmax(0, 1fr);
    gap: 24px;
    padding: 28px var(--pad) 24px;
  }

  .footer-bottom {
    padding: 16px var(--pad) 22px;
    flex-direction: column;
    align-items: flex-start;
    gap: 8px;
  }

  .footer-bottom-links {
    gap: 14px;
  }

  .footer-links a {
    display: inline-flex;
    align-items: center;
    min-height: 32px;
  }
}

@media (max-width: 480px) {
  .hero-actions .btn,
  .cta-actions .btn {
    flex: 1 1 100%;
  }

  .data-table tbody td {
    flex-direction: column;
    gap: 2px;
  }

  .data-table tbody td::before {
    flex: none;
    font-size: 12px;
  }

  .precheck-list li {
    flex-direction: column;
    gap: 6px;
  }
}

@media (prefers-reduced-motion: reduce) {
  .btn,
  .nav-list a,
  .channel-tags a,
  .anchor-row a,
  .related-list a,
  .error-link-list a {
    transition: none;
  }
}