/* ==========================================================================
   九九电影网 · 全站样式表
   分组：base / layout / components / pages / responsive
   ========================================================================== */

/* --------------------------------------------------------------------------
   base · 变量与全局基础
   -------------------------------------------------------------------------- */
:root {
  --page-bg: #f4f5f7;
  --card-bg: #ffffff;
  --brand-blue: #1c3f6e;
  --brand-blue-dark: #142e51;
  --brand-red: #a8322d;
  --text-main: #1f2329;
  --text-muted: #5a6472;
  --line: #d9dde3;
  --tint: #e8edf4;
  --radius: 6px;
  --radius-sm: 4px;
  --shadow-card: 0 1px 2px rgba(28, 63, 110, 0.06);
  --font-stack: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Source Han Sans SC", "Noto Sans CJK SC", Arial, sans-serif;
  --content-width: 1180px;
}

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

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

body {
  margin: 0;
  background: var(--page-bg);
  color: var(--text-main);
  font-family: var(--font-stack);
  font-size: 16px;
  line-height: 1.75;
}

h1,
h2,
h3,
h4 {
  margin: 0;
  font-weight: 700;
  color: var(--brand-blue);
}

p {
  margin: 0;
}

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

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

a:hover {
  color: var(--brand-red);
}

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

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

figure {
  margin: 0;
}

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

/* --------------------------------------------------------------------------
   layout · 骨架：页头 / 主内容 / 页脚
   -------------------------------------------------------------------------- */
.site-body {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  background: var(--page-bg);
  color: var(--text-main);
  font-family: var(--font-stack);
  font-size: 16px;
  line-height: 1.75;
}

/* 顶部信息条（仅首页） */
.top-bar {
  background: var(--brand-blue-dark);
  color: #dce4ef;
}

.top-bar-text {
  max-width: var(--content-width);
  margin: 0 auto;
  padding: 7px 20px;
  font-size: 13px;
  line-height: 1.6;
}

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

.header-inner {
  max-width: var(--content-width);
  margin: 0 auto;
  padding: 0 20px;
  min-height: 62px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
}

.brand {
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  font-size: 20px;
  font-weight: 700;
  color: var(--brand-blue);
  letter-spacing: 0;
}

.brand:hover {
  color: var(--brand-red);
}

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

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

.nav-link {
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  padding: 0 12px;
  font-size: 15px;
  color: var(--text-main);
  border-bottom: 2px solid transparent;
}

.nav-link:hover {
  color: var(--brand-blue);
  border-bottom-color: var(--line);
}

.nav-link.is-current {
  color: var(--brand-blue);
  font-weight: 700;
  border-bottom-color: var(--brand-red);
}

/* 目录按钮：桌面隐藏，移动显示 */
.nav-toggle {
  display: none;
  width: 44px;
  height: 44px;
  padding: 0;
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
  background: var(--card-bg);
  cursor: pointer;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 5px;
}

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

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

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

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

/* 主内容区 */
.site-main {
  flex: 1 0 auto;
  width: 100%;
}

.inner-main {
  max-width: var(--content-width);
  margin: 0 auto;
  padding: 22px 20px 48px;
}

.home-main {
  width: 100%;
}

/* 面包屑 */
.breadcrumb {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 6px;
  font-size: 13px;
  color: var(--text-muted);
  margin-bottom: 14px;
}

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

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

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

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

/* 页面标题区 */
.page-header {
  padding-bottom: 18px;
  margin-bottom: 24px;
  border-bottom: 1px solid var(--line);
}

.page-title {
  font-size: 30px;
  line-height: 1.3;
  letter-spacing: 0;
}

.page-description {
  margin-top: 10px;
  max-width: 860px;
  font-size: 15px;
  color: var(--text-muted);
}

/* 页脚 */
.site-footer {
  background: var(--brand-blue);
  color: #d7dfeb;
  margin-top: 40px;
}

.footer-inner {
  max-width: var(--content-width);
  margin: 0 auto;
  padding: 38px 20px 26px;
  display: grid;
  grid-template-columns: 1.6fr 1fr 1fr 1fr;
  gap: 28px;
}

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

.footer-brand-name {
  font-size: 17px;
  font-weight: 700;
  color: #ffffff;
  margin-bottom: 8px;
}

.footer-brand-text {
  font-size: 13px;
  line-height: 1.7;
  color: #b9c6da;
  max-width: 360px;
}

.footer-list li + li {
  margin-top: 8px;
}

.footer-list a {
  display: inline-block;
  min-height: 26px;
  font-size: 13px;
  color: #d7dfeb;
}

.footer-list a:hover {
  color: #ffffff;
  text-decoration: underline;
}

.footer-meta-text {
  font-size: 13px;
  color: #b9c6da;
  line-height: 1.7;
}

.footer-copy {
  margin-top: 10px;
  font-size: 13px;
  color: #93a4bd;
}

/* --------------------------------------------------------------------------
   components · 通用元素
   -------------------------------------------------------------------------- */
.section {
  margin-bottom: 40px;
}

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

.section-title {
  font-size: 22px;
  line-height: 1.4;
  letter-spacing: 0;
}

.section-desc {
  margin-top: 8px;
  font-size: 14px;
  color: var(--text-muted);
  max-width: 860px;
}

.section-intro,
.section-lead {
  margin-top: 8px;
  margin-bottom: 16px;
  font-size: 15px;
  color: var(--text-muted);
  max-width: 860px;
}

.sub-title {
  font-size: 17px;
  line-height: 1.45;
  margin-bottom: 10px;
}

.subsection-title {
  font-size: 16px;
  line-height: 1.45;
  margin-bottom: 10px;
}

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

.text-link {
  display: inline-flex;
  align-items: center;
  min-height: 30px;
  font-size: 14px;
  font-weight: 700;
  color: var(--brand-red);
  border-bottom: 1px solid transparent;
}

.text-link:hover {
  color: var(--brand-blue);
  border-bottom-color: var(--brand-blue);
}

/* 按钮 */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 44px;
  padding: 0 20px;
  border-radius: var(--radius-sm);
  font-size: 15px;
  font-weight: 700;
  border: 1px solid transparent;
}

.btn-primary {
  background: var(--brand-blue);
  color: #ffffff;
}

.btn-primary:hover {
  background: var(--brand-blue-dark);
  color: #ffffff;
}

.btn-ghost {
  background: var(--card-bg);
  color: var(--brand-blue);
  border-color: var(--brand-blue);
}

.btn-ghost:hover {
  background: var(--tint);
  color: var(--brand-blue-dark);
}

/* 通用表格外观 */
.data-table,
.field-table {
  width: 100%;
  background: var(--card-bg);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
  font-size: 14px;
}

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

.data-table th,
.data-table td,
.field-table th,
.field-table td {
  padding: 11px 14px;
  text-align: left;
  vertical-align: top;
  border-bottom: 1px solid var(--line);
  line-height: 1.65;
}

.data-table thead th,
.field-table thead th {
  background: var(--tint);
  color: var(--brand-blue);
  font-weight: 700;
  white-space: nowrap;
}

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

.data-table tbody tr:hover,
.field-table tbody tr:hover {
  background: #f8fafc;
}

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

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

/* 图片容器统一约束 */
.hero-figure,
.topic-media,
.topic-figure,
.section-figure,
.updates-figure,
.guide-figure {
  overflow: hidden;
  border-radius: var(--radius);
  background: var(--tint);
}

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

.figure-caption,
.updates-figure-caption {
  padding: 10px 14px;
  font-size: 13px;
  color: var(--text-muted);
  background: var(--card-bg);
  border-top: 1px solid var(--line);
}

/* --------------------------------------------------------------------------
   pages · 首页
   -------------------------------------------------------------------------- */
.hero {
  background: var(--card-bg);
  border-bottom: 1px solid var(--line);
}

.hero-layout {
  max-width: var(--content-width);
  margin: 0 auto;
  padding: 40px 20px 26px;
  display: grid;
  grid-template-columns: minmax(0, 1.05fr) minmax(0, 0.95fr);
  gap: 36px;
  align-items: center;
}

.hero-eyebrow {
  font-size: 13px;
  color: var(--brand-red);
  font-weight: 700;
  margin-bottom: 10px;
}

.hero-title {
  font-size: 30px;
  line-height: 1.3;
  letter-spacing: 0;
}

.hero-lead {
  margin-top: 14px;
  font-size: 15px;
  color: var(--text-muted);
  max-width: 560px;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 22px;
}

.hero-figure {
  aspect-ratio: 16 / 10;
  border: 1px solid var(--line);
}

.hero-facts {
  max-width: var(--content-width);
  margin: 0 auto;
  padding: 0 20px 34px;
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 14px;
}

.hero-fact {
  background: var(--card-bg);
  border: 1px solid var(--line);
  border-left: 3px solid var(--brand-blue);
  border-radius: var(--radius-sm);
  padding: 12px 14px;
}

.fact-label {
  display: block;
  font-size: 13px;
  font-weight: 700;
  color: var(--brand-red);
  margin-bottom: 4px;
}

.fact-text {
  display: block;
  font-size: 14px;
  color: var(--text-muted);
}

.home-main .section {
  max-width: var(--content-width);
  margin: 0 auto 40px;
  padding: 0 20px;
}

.home-main .section:first-of-type {
  margin-top: 34px;
}

/* 频道分类总览：四列行式 */
.channel-table {
  display: block;
  background: var(--card-bg);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
}

.channel-row {
  display: grid;
  grid-template-columns: 1.1fr 1.5fr 1.6fr 1.2fr;
  border-bottom: 1px solid var(--line);
}

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

.channel-row-head {
  background: var(--tint);
  font-weight: 700;
  color: var(--brand-blue);
  font-size: 14px;
}

.channel-row:not(.channel-row-head):hover {
  background: #f8fafc;
}

.channel-table .cell {
  padding: 12px 14px;
  font-size: 14px;
  line-height: 1.65;
  border-right: 1px solid var(--line);
  min-width: 0;
}

.channel-table .cell:last-child {
  border-right: 0;
}

.channel-table .cell-name {
  font-weight: 700;
}

.channel-table .cell-name a {
  display: inline-block;
  min-height: 24px;
}

.channel-table .cell-type {
  color: var(--text-muted);
}

/* 专题合集入口：两列卡片 */
.topic-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 18px;
}

.topic-card {
  display: flex;
  flex-direction: column;
  background: var(--card-bg);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
  transition: border-color 0.18s ease, background-color 0.18s ease;
}

.topic-card:hover {
  border-color: var(--brand-blue);
  background: #fbfcfe;
}

.topic-media {
  aspect-ratio: 16 / 9;
  border-bottom: 1px solid var(--line);
  border-radius: 0;
}

.topic-body {
  padding: 14px 16px 16px;
}

.topic-name {
  font-size: 17px;
  line-height: 1.45;
  margin-bottom: 8px;
}

.topic-scope {
  font-size: 14px;
  color: var(--text-main);
}

.topic-count {
  margin-top: 8px;
  font-size: 13px;
  color: var(--text-muted);
}

/* 更新线索速览：三列月份分组 */
.update-months {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 18px;
}

.update-month {
  background: var(--card-bg);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 16px;
}

.month-name {
  font-size: 16px;
  line-height: 1.45;
  padding-bottom: 10px;
  margin-bottom: 10px;
  border-bottom: 1px solid var(--line);
}

.update-list li + li {
  margin-top: 12px;
  padding-top: 12px;
  border-top: 1px dashed var(--line);
}

.update-date {
  display: inline-block;
  font-size: 13px;
  font-weight: 700;
  color: var(--brand-red);
  margin-right: 8px;
}

.update-channel,
.update-topic {
  display: inline-block;
  font-size: 12px;
  color: var(--brand-blue);
  background: var(--tint);
  border-radius: var(--radius-sm);
  padding: 1px 7px;
  margin-right: 6px;
}

.update-note {
  margin-top: 6px;
  font-size: 14px;
  color: var(--text-muted);
}

/* 字段说明与浏览指引摘要：左右双栏 */
.fields-layout {
  display: grid;
  grid-template-columns: minmax(0, 1.15fr) minmax(0, 0.85fr);
  gap: 24px;
  align-items: start;
}

.fields-table-wrap {
  min-width: 0;
}

.field-table[role="table"] {
  display: block;
  overflow: hidden;
}

.field-row {
  display: grid;
  grid-template-columns: 0.9fr 1.6fr 1.5fr;
  border-bottom: 1px solid var(--line);
}

.field-row:last-child {
  border-bottom: 0;
}

.field-row-head {
  background: var(--tint);
  font-weight: 700;
  color: var(--brand-blue);
  font-size: 14px;
}

.field-table .cell {
  padding: 11px 14px;
  font-size: 14px;
  line-height: 1.65;
  border-right: 1px solid var(--line);
  min-width: 0;
}

.field-table .cell:last-child {
  border-right: 0;
}

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

.fields-text {
  font-size: 14px;
  color: var(--text-muted);
}

.order-list {
  margin-top: 14px;
  counter-reset: order;
}

.order-item {
  position: relative;
  padding-left: 30px;
  font-size: 14px;
  color: var(--text-main);
}

.order-item + .order-item {
  margin-top: 12px;
}

.order-item::before {
  counter-increment: order;
  content: counter(order);
  position: absolute;
  left: 0;
  top: 2px;
  width: 20px;
  height: 20px;
  border-radius: 50%;
  background: var(--brand-blue);
  color: #ffffff;
  font-size: 12px;
  font-weight: 700;
  display: flex;
  align-items: center;
  justify-content: center;
}

.fields-more {
  margin-top: 14px;
}

/* 站内页面索引：四列 */
.index-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 16px;
}

.index-card {
  background: var(--card-bg);
  border: 1px solid var(--line);
  border-top: 3px solid var(--brand-blue);
  border-radius: var(--radius-sm);
  padding: 16px;
  transition: border-color 0.18s ease, background-color 0.18s ease;
}

.index-card:hover {
  border-color: var(--brand-blue);
  background: #fbfcfe;
}

.index-name {
  font-size: 16px;
  line-height: 1.45;
  margin-bottom: 8px;
}

.index-name a {
  display: inline-block;
  min-height: 26px;
}

.index-desc {
  font-size: 14px;
  color: var(--text-muted);
}

/* --------------------------------------------------------------------------
   pages · 内页通用布局
   -------------------------------------------------------------------------- */
.page-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 26px;
  align-items: start;
}

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

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

/* 侧栏 */
.channel-index,
.topic-sidebar {
  background: var(--card-bg);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 16px;
}

.aside-title,
.sidebar-title {
  font-size: 16px;
  line-height: 1.45;
  margin-bottom: 8px;
}

.aside-note,
.sidebar-note {
  font-size: 13px;
  color: var(--text-muted);
  margin-bottom: 12px;
}

.channel-index-list li + li,
.sidebar-list li + li {
  margin-top: 4px;
}

.channel-index-link,
.sidebar-list a {
  display: block;
  min-height: 40px;
  padding: 8px 10px;
  font-size: 14px;
  border-radius: var(--radius-sm);
  border-left: 3px solid transparent;
  color: var(--text-main);
}

.channel-index-link:hover,
.sidebar-list a:hover {
  background: var(--tint);
  color: var(--brand-blue);
}

.channel-index-link.is-current {
  background: var(--tint);
  border-left-color: var(--brand-red);
  color: var(--brand-blue);
  font-weight: 700;
}

.sidebar-list a {
  border-left: 3px solid var(--line);
}

.sidebar-note a {
  color: var(--brand-red);
  font-weight: 700;
}

/* --------------------------------------------------------------------------
   pages · 频道分类
   -------------------------------------------------------------------------- */
.channel-overview .section-figure {
  margin: 16px 0 20px;
  border: 1px solid var(--line);
}

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

.channel-block {
  background: var(--card-bg);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 18px;
}

.channel-block + .channel-block {
  margin-top: 16px;
}

.block-title {
  font-size: 17px;
  line-height: 1.45;
  margin-bottom: 8px;
}

.block-text {
  font-size: 15px;
  color: var(--text-main);
}

.block-list {
  margin-top: 12px;
}

.block-list li {
  position: relative;
  padding-left: 18px;
  font-size: 14px;
  color: var(--text-muted);
}

.block-list li + li {
  margin-top: 8px;
}

.block-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 10px;
  width: 6px;
  height: 6px;
  background: var(--brand-red);
  border-radius: 1px;
}

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

.column-block {
  background: var(--card-bg);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 18px;
}

.column-title {
  font-size: 16px;
  line-height: 1.45;
  margin-bottom: 8px;
}

.column-text {
  font-size: 14px;
  color: var(--text-muted);
}

/* --------------------------------------------------------------------------
   pages · 专题合集
   -------------------------------------------------------------------------- */
.topic-group {
  background: var(--card-bg);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 18px;
}

.topic-group + .topic-group {
  margin-top: 18px;
}

.topic-figure {
  margin-bottom: 14px;
  border: 1px solid var(--line);
}

.topic-figure img {
  aspect-ratio: 16 / 7;
}

.topic-group .topic-name {
  font-size: 18px;
  margin-bottom: 10px;
}

.topic-meta {
  margin: 0;
  display: grid;
  grid-template-columns: 96px minmax(0, 1fr);
  gap: 6px 14px;
  font-size: 14px;
}

.topic-meta dt {
  color: var(--brand-blue);
  font-weight: 700;
}

.topic-meta dd {
  margin: 0;
  color: var(--text-muted);
}

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

.topic-link a {
  font-weight: 700;
  color: var(--brand-red);
}

.topic-link a:hover {
  color: var(--brand-blue);
}

.topic-usage {
  margin-top: 34px;
}

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

.usage-col {
  background: var(--card-bg);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 18px;
}

.usage-title {
  font-size: 16px;
  line-height: 1.45;
  margin-bottom: 10px;
}

.usage-list li {
  position: relative;
  padding-left: 18px;
  font-size: 14px;
  color: var(--text-muted);
}

.usage-list li + li {
  margin-top: 8px;
}

.usage-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 10px;
  width: 6px;
  height: 6px;
  background: var(--brand-blue);
  border-radius: 1px;
}

/* --------------------------------------------------------------------------
   pages · 更新线索
   -------------------------------------------------------------------------- */
.updates-intro {
  margin-bottom: 36px;
}

.updates-intro-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.25fr) minmax(0, 0.75fr);
  gap: 24px;
  align-items: start;
}

.updates-intro-col {
  background: var(--card-bg);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 18px;
}

.updates-intro-col p {
  font-size: 14px;
  color: var(--text-muted);
}

.updates-intro-col p + p {
  margin-top: 10px;
}

.updates-note-list {
  margin-top: 14px;
}

.updates-note-list li {
  position: relative;
  padding-left: 18px;
  font-size: 14px;
  color: var(--text-main);
}

.updates-note-list li + li {
  margin-top: 8px;
}

.updates-note-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 10px;
  width: 6px;
  height: 6px;
  background: var(--brand-red);
  border-radius: 1px;
}

.updates-intro-aside {
  background: var(--card-bg);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 18px;
}

.updates-intro-tip {
  margin-top: 12px;
  font-size: 14px;
}

.updates-timeline {
  margin-bottom: 36px;
}

.month-jump {
  margin-bottom: 18px;
}

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

.month-jump-list a {
  display: inline-flex;
  align-items: center;
  min-height: 36px;
  padding: 0 14px;
  font-size: 14px;
  background: var(--card-bg);
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
  color: var(--brand-blue);
}

.month-jump-list a:hover {
  border-color: var(--brand-blue);
  background: var(--tint);
}

.updates-figure {
  margin-bottom: 24px;
  border: 1px solid var(--line);
}

.updates-figure img {
  aspect-ratio: 21 / 8;
}

.timeline {
  position: relative;
  padding-left: 26px;
  border-left: 2px solid var(--line);
}

.timeline-month + .timeline-month {
  margin-top: 30px;
}

.timeline-month-title {
  position: relative;
  font-size: 18px;
  line-height: 1.45;
  margin-bottom: 14px;
}

.timeline-month-title::before {
  content: "";
  position: absolute;
  left: -34px;
  top: 8px;
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: var(--brand-blue);
  border: 2px solid var(--card-bg);
}

.timeline-item {
  background: var(--card-bg);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 14px 16px;
}

.timeline-item + .timeline-item {
  margin-top: 12px;
}

.timeline-date {
  font-size: 13px;
  font-weight: 700;
  color: var(--brand-red);
}

.timeline-meta {
  margin-top: 4px;
  font-size: 13px;
  color: var(--brand-blue);
}

.timeline-text {
  margin-top: 8px;
  font-size: 14px;
  color: var(--text-main);
}

.updates-related-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 16px;
}

.updates-related-card {
  background: var(--card-bg);
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
  padding: 16px;
  transition: border-color 0.18s ease, background-color 0.18s ease;
}

.updates-related-card:hover {
  border-color: var(--brand-blue);
  background: #fbfcfe;
}

.updates-related-name {
  font-size: 16px;
  line-height: 1.45;
  margin-bottom: 8px;
}

.updates-related-name a {
  display: inline-block;
  min-height: 26px;
}

.updates-related-text {
  font-size: 14px;
  color: var(--text-muted);
}

/* --------------------------------------------------------------------------
   pages · 浏览指引
   -------------------------------------------------------------------------- */
.guide-side {
  background: var(--card-bg);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 18px;
  min-width: 0;
}

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

.content-block {
  background: var(--card-bg);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 18px;
}

.content-block + .content-block {
  margin-top: 18px;
}

.order-columns {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 20px;
  margin-top: 6px;
}

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

.point-list li {
  position: relative;
  padding-left: 18px;
  font-size: 14px;
  color: var(--text-muted);
}

.point-list li + li {
  margin-top: 8px;
}

.point-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 10px;
  width: 6px;
  height: 6px;
  background: var(--brand-blue);
  border-radius: 1px;
}

.guide-figure {
  margin: 16px 0;
  border: 1px solid var(--line);
}

.guide-figure img {
  aspect-ratio: 16 / 7;
}

.side-note {
  margin-top: 12px;
  font-size: 13px;
  color: var(--text-muted);
}

/* 浏览顺序步骤条 */
.step-list {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 16px;
  margin-top: 16px;
}

.step-item {
  background: var(--card-bg);
  border: 1px solid var(--line);
  border-top: 3px solid var(--brand-blue);
  border-radius: var(--radius-sm);
  padding: 16px;
}

.step-index {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 26px;
  height: 26px;
  border-radius: 50%;
  background: var(--brand-blue);
  color: #ffffff;
  font-size: 13px;
  font-weight: 700;
  margin-bottom: 8px;
}

.step-name {
  font-size: 16px;
  line-height: 1.45;
  margin-bottom: 6px;
}

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

.step-details {
  margin-top: 12px;
}

.step-body {
  font-size: 14px;
}

.step-action {
  color: var(--text-main);
}

.step-expect {
  margin-top: 6px;
  color: var(--brand-blue);
}

.step-fallback {
  margin-top: 8px;
  font-size: 13px;
  color: var(--text-muted);
  background: var(--tint);
  border-radius: var(--radius-sm);
  padding: 8px 10px;
}

/* 收录边界 */
.scope-columns {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 20px;
  margin-top: 6px;
}

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

/* 相关入口 */
.related-block .related-list {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 12px;
  margin-top: 8px;
}

.related-item {
  background: var(--card-bg);
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
  padding: 12px 14px;
  font-size: 14px;
}

.related-item a {
  display: inline-block;
  min-height: 26px;
  font-weight: 700;
}

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

/* 常见问题（若页面使用） */
.faq-list {
  margin-top: 6px;
}

.faq-item {
  background: var(--card-bg);
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
  padding: 14px 16px;
}

.faq-item + .faq-item {
  margin-top: 12px;
}

.faq-question {
  font-size: 15px;
  font-weight: 700;
  color: var(--brand-blue);
}

.faq-answer {
  margin-top: 8px;
  font-size: 14px;
  color: var(--text-muted);
}

/* --------------------------------------------------------------------------
   pages · 404
   -------------------------------------------------------------------------- */
.error-main {
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 60px 20px;
}

.error-inner {
  max-width: 640px;
  width: 100%;
  background: var(--card-bg);
  border: 1px solid var(--line);
  border-top: 3px solid var(--brand-red);
  border-radius: var(--radius);
  padding: 30px;
  text-align: left;
}

.error-code {
  font-size: 40px;
  font-weight: 700;
  color: var(--brand-red);
  line-height: 1.1;
}

.error-title {
  font-size: 24px;
  line-height: 1.35;
  margin-top: 8px;
}

.error-text {
  margin-top: 12px;
  font-size: 15px;
  color: var(--text-muted);
}

.error-action {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 44px;
  margin-top: 20px;
  padding: 0 20px;
  background: var(--brand-blue);
  color: #ffffff;
  border-radius: var(--radius-sm);
  font-size: 15px;
  font-weight: 700;
}

.error-action:hover {
  background: var(--brand-blue-dark);
  color: #ffffff;
}

.error-links {
  margin-top: 26px;
  padding-top: 18px;
  border-top: 1px solid var(--line);
}

.error-links-title {
  font-size: 16px;
  line-height: 1.45;
  margin-bottom: 10px;
}

.error-links-list {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 10px;
}

.error-links-list a {
  display: inline-flex;
  align-items: center;
  min-height: 40px;
  padding: 0 12px;
  font-size: 14px;
  background: var(--tint);
  border-radius: var(--radius-sm);
  color: var(--brand-blue);
}

.error-links-list a:hover {
  background: #dbe4f0;
  color: var(--brand-red);
}

/* --------------------------------------------------------------------------
   responsive · 平板与手机
   -------------------------------------------------------------------------- */
@media (max-width: 1023px) {
  .hero-layout {
    grid-template-columns: minmax(0, 1fr);
    gap: 24px;
    padding-top: 30px;
  }

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

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

  .channel-row {
    grid-template-columns: 1fr 1.4fr 1.4fr;
  }

  .channel-table .cell-type {
    display: none;
  }

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

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

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

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

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

@media (max-width: 767px) {
  body {
    font-size: 15px;
    line-height: 1.7;
  }

  .top-bar-text {
    padding: 7px 16px;
  }

  .header-inner {
    padding: 0 16px;
    gap: 12px;
  }

  .brand {
    font-size: 18px;
  }

  .nav-toggle {
    display: flex;
  }

  .site-nav {
    position: relative;
  }

  .nav-list {
    display: none;
    position: absolute;
    top: calc(100% + 12px);
    right: 0;
    width: min(280px, calc(100vw - 32px));
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    background: var(--card-bg);
    border: 1px solid var(--line);
    border-radius: var(--radius);
    box-shadow: 0 8px 20px rgba(28, 63, 110, 0.12);
    padding: 6px;
    z-index: 50;
  }

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

  .nav-link {
    min-height: 44px;
    padding: 0 12px;
    border-bottom: 0;
    border-left: 3px solid transparent;
    border-radius: var(--radius-sm);
  }

  .nav-link:hover {
    background: var(--tint);
    border-bottom-color: transparent;
  }

  .nav-link.is-current {
    background: var(--tint);
    border-left-color: var(--brand-red);
    border-bottom-color: transparent;
  }

  .inner-main {
    padding: 18px 16px 40px;
  }

  .page-title {
    font-size: 24px;
    line-height: 1.35;
  }

  .section-title {
    font-size: 19px;
  }

  .hero-layout {
    padding: 26px 16px 20px;
  }

  .hero-title {
    font-size: 24px;
    line-height: 1.35;
  }

  .hero-facts {
    grid-template-columns: minmax(0, 1fr);
    padding: 0 16px 26px;
  }

  .home-main .section {
    padding: 0 16px;
    margin-bottom: 32px;
  }

  .channel-table .cell-feature {
    display: none;
  }

  .channel-row {
    grid-template-columns: 1fr 1.3fr;
  }

  .topic-grid,
  .update-months,
  .index-grid,
  .updates-related-grid,
  .split-columns,
  .usage-columns,
  .order-columns,
  .scope-columns,
  .related-block .related-list,
  .error-links-list {
    grid-template-columns: minmax(0, 1fr);
  }

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

  .field-row {
    grid-template-columns: 1fr 1.4fr;
  }

  .field-table .cell:last-child {
    display: none;
  }

  .topic-meta {
    grid-template-columns: 84px minmax(0, 1fr);
  }

  .timeline {
    padding-left: 18px;
  }

  .timeline-month-title::before {
    left: -26px;
  }

  .footer-inner {
    grid-template-columns: minmax(0, 1fr);
    gap: 22px;
    padding: 28px 16px 22px;
  }

  .footer-brand-text {
    max-width: none;
  }

  .error-main {
    padding: 40px 16px;
  }

  .error-inner {
    padding: 22px;
  }

  .error-code {
    font-size: 32px;
  }

  .error-title {
    font-size: 20px;
  }
}