/* ==========================================================================
   九九在线视频 · 全站样式
   基础 · 布局 · 组件 · 页面 · 响应式
   ========================================================================== */

/* ==========================================================================
   base —— 变量、重置、排版基准
   ========================================================================== */

:root {
  --bg-page: #f5f6f8;
  --bg-surface: #ffffff;
  --bg-soft: #eceef1;
  --ink: #1f2328;
  --ink-muted: #5b6470;
  --ink-faint: #7d8694;
  --line: #d0d7de;
  --line-soft: #e3e7ec;
  --blue: #1f6feb;
  --green: #2da44e;
  --amber: #bf8700;
  --purple: #8250df;
  --red: #cf222e;
  --radius: 6px;
  --radius-sm: 4px;
  --wrap: 1120px;
  --gap: 20px;
  --shadow: 0 1px 2px rgba(31, 35, 40, 0.06);
  --font-sans: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Source Han Sans SC", "Noto Sans CJK SC", system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  --font-mono: "SFMono-Regular", "JetBrains Mono", Consolas, "Liberation Mono", Menlo, monospace;
}

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

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

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

h1,
h2,
h3,
h4 {
  margin: 0;
  line-height: 1.3;
  font-weight: 700;
  color: var(--ink);
}

p {
  margin: 0;
}

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

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

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

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

button {
  font: inherit;
  color: inherit;
}

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

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

/* ==========================================================================
   layout —— 骨架：页头、导航、主容器、面包屑、页标题、页脚
   ========================================================================== */

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

.header-inner {
  max-width: var(--wrap);
  margin: 0 auto;
  padding: 0 20px;
  min-height: 64px;
  display: flex;
  align-items: center;
  gap: 16px;
}

.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  color: var(--ink);
  text-decoration: none;
  flex: 0 0 auto;
}

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

.brand-mark {
  width: 30px;
  height: 30px;
  border-radius: var(--radius-sm);
  background: var(--blue);
  position: relative;
  flex: 0 0 auto;
}

.brand-mark::before,
.brand-mark::after {
  content: "";
  position: absolute;
  left: 6px;
  right: 6px;
  height: 3px;
  border-radius: 2px;
  background: #ffffff;
}

.brand-mark::before {
  top: 9px;
}

.brand-mark::after {
  top: 17px;
  right: 12px;
}

.brand-text {
  display: flex;
  flex-direction: column;
  line-height: 1.25;
}

.brand-name {
  font-size: 17px;
  font-weight: 700;
}

.brand-slogan {
  font-size: 12px;
  color: var(--ink-muted);
}

.nav-toggle {
  display: none;
  align-items: center;
  gap: 6px;
  margin-left: auto;
  padding: 8px 12px;
  min-height: 44px;
  background: var(--bg-surface);
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
  cursor: pointer;
}

.nav-toggle-icon {
  width: 16px;
  height: 12px;
  position: relative;
  flex: 0 0 auto;
}

.nav-toggle-icon::before,
.nav-toggle-icon::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  height: 2px;
  background: var(--ink);
}

.nav-toggle-icon::before {
  top: 0;
  box-shadow: 0 5px 0 var(--ink);
}

.nav-toggle-icon::after {
  bottom: 0;
}

.nav-toggle-text {
  font-size: 14px;
}

.site-nav {
  margin-left: auto;
}

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

.nav-link {
  display: block;
  padding: 8px 12px;
  font-size: 15px;
  color: var(--ink);
  border-bottom: 2px solid transparent;
}

.nav-link:hover {
  color: var(--blue);
  text-decoration: none;
}

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

.site-main {
  display: block;
}

.inner-main {
  max-width: var(--wrap);
  margin: 0 auto;
  padding: 24px 20px 56px;
}

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

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

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

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

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

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

.page-title {
  font-size: 28px;
  line-height: 1.35;
}

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

.page-lead {
  margin-top: 10px;
  font-size: 14px;
  color: var(--ink-muted);
}

.page-lead a {
  margin-right: 12px;
}

.site-footer {
  margin-top: 40px;
  background: var(--bg-surface);
  border-top: 1px solid var(--line);
}

.footer-inner {
  max-width: var(--wrap);
  margin: 0 auto;
  padding: 32px 20px 8px;
  display: grid;
  grid-template-columns: minmax(0, 1.4fr) minmax(0, 1fr) minmax(0, 1.2fr);
  gap: 28px;
}

.footer-name {
  font-size: 16px;
  font-weight: 700;
  margin-bottom: 8px;
}

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

.footer-nav-title,
.footer-note-title {
  font-size: 14px;
  margin-bottom: 10px;
}

.footer-nav-list {
  display: grid;
  gap: 6px;
}

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

.footer-nav-list a:hover {
  color: var(--blue);
}

.footer-note-text {
  font-size: 13px;
  color: var(--ink-muted);
  margin-bottom: 10px;
}

.back-top {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 6px 12px;
  font-size: 13px;
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
  color: var(--ink);
  background: var(--bg-page);
}

.back-top::before {
  content: "";
  width: 8px;
  height: 8px;
  border-left: 2px solid currentColor;
  border-top: 2px solid currentColor;
  transform: rotate(45deg);
}

.back-top:hover {
  border-color: var(--blue);
  color: var(--blue);
  text-decoration: none;
}

.footer-copy {
  max-width: var(--wrap);
  margin: 0 auto;
  padding: 14px 20px 24px;
  font-size: 12px;
  color: var(--ink-faint);
  border-top: 1px solid var(--line-soft);
}

/* ==========================================================================
   components —— 通用组件
   ========================================================================== */

.section {
  margin-bottom: 44px;
}

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

.section-title {
  font-size: 21px;
  padding-left: 12px;
  border-left: 4px solid var(--blue);
}

.section-desc,
.section-intro {
  margin-top: 8px;
  font-size: 14px;
  color: var(--ink-muted);
  max-width: 880px;
}

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

.text-link {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-weight: 700;
}

.text-link::after {
  content: "→";
  font-weight: 400;
}

.tag {
  display: inline-block;
  padding: 1px 8px;
  font-size: 12px;
  line-height: 1.6;
  border-radius: 10px;
  border: 1px solid currentColor;
}

.tag-add {
  color: var(--green);
}

.tag-adjust {
  color: var(--amber);
}

.tag-field {
  color: var(--purple);
}

.tag-scope {
  display: inline-block;
  padding: 1px 8px;
  font-size: 12px;
  line-height: 1.6;
  border-radius: 10px;
  border: 1px solid var(--line);
  color: var(--ink-muted);
  background: var(--bg-page);
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 44px;
  padding: 10px 18px;
  border-radius: var(--radius);
  border: 1px solid transparent;
  font-size: 15px;
  cursor: pointer;
}

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

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

.btn-primary:hover {
  background: #1a5fd0;
}

.btn-secondary {
  background: var(--bg-surface);
  border-color: var(--line);
  color: var(--ink);
}

.btn-secondary:hover {
  border-color: var(--blue);
  color: var(--blue);
}

.btn-ghost {
  background: transparent;
  border-color: var(--line);
  color: var(--ink-muted);
}

.btn-ghost:hover {
  border-color: var(--ink-muted);
  color: var(--ink);
}

/* 表格：字段说明 */
.table-wrap {
  overflow-x: auto;
  background: var(--bg-surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.field-table {
  min-width: 560px;
  font-size: 14px;
}

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

.field-table th,
.field-table td {
  padding: 10px 14px;
  text-align: left;
  border-bottom: 1px solid var(--line-soft);
  vertical-align: top;
}

.field-table thead th {
  background: var(--bg-soft);
  font-size: 13px;
  color: var(--ink-muted);
  white-space: nowrap;
}

.field-table tbody th {
  font-weight: 700;
  white-space: nowrap;
  font-family: var(--font-mono);
  font-size: 13px;
}

.field-table tbody tr:last-child th,
.field-table tbody tr:last-child td {
  border-bottom: none;
}

/* 图片容器 */
figure {
  margin: 0;
}

figcaption {
  margin-top: 8px;
  font-size: 13px;
  color: var(--ink-muted);
}

/* 分步清单：首页与观看指引共用结构，父级分别限定 */
.step-list {
  display: grid;
  gap: 12px;
}

.step-item {
  display: flex;
  gap: 14px;
  padding: 14px 16px;
  background: var(--bg-surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.step-no {
  flex: 0 0 auto;
  width: 26px;
  height: 26px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border-radius: 50%;
  background: var(--blue);
  color: #ffffff;
  font-size: 13px;
  font-family: var(--font-mono);
}

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

.step-name,
.step-title {
  font-size: 16px;
  margin-bottom: 4px;
}

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

/* ==========================================================================
   pages —— 首页
   ========================================================================== */

.home-main {
  display: block;
}

.hero {
  background: var(--bg-surface);
  border-bottom: 1px solid var(--line);
}

.hero-grid {
  max-width: var(--wrap);
  margin: 0 auto;
  padding: 36px 20px 32px;
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1.05fr);
  gap: 32px;
  align-items: start;
}

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

.hero-kicker {
  display: inline-block;
  padding: 3px 10px;
  font-size: 12px;
  color: var(--blue);
  border: 1px solid var(--blue);
  border-radius: 10px;
  margin-bottom: 12px;
}

.hero-title {
  font-size: 32px;
  line-height: 1.35;
}

.hero-text {
  margin-top: 14px;
  font-size: 15px;
  color: var(--ink-muted);
  max-width: 520px;
}

.hero-actions {
  margin-top: 22px;
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.hero-media {
  min-width: 0;
  display: grid;
  gap: 18px;
}

.hero-figure img {
  width: 100%;
  height: 240px;
  object-fit: cover;
  border-radius: var(--radius);
  border: 1px solid var(--line);
  background: var(--bg-soft);
}

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

.hero-timeline-title {
  font-size: 14px;
  color: var(--ink-muted);
  margin-bottom: 10px;
}

.mini-timeline {
  display: grid;
  gap: 8px;
}

.mini-timeline-item {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 8px;
  font-size: 13px;
  padding-left: 12px;
  border-left: 2px solid var(--line);
}

.mini-timeline-type {
  color: var(--blue);
  font-weight: 700;
}

.mini-timeline-scope {
  color: var(--ink-muted);
}

/* 首页 · 线路式频道总览 */
.channels-layout {
  display: grid;
  grid-template-columns: minmax(0, 1.35fr) minmax(0, 1fr);
  gap: 24px;
  align-items: start;
}

.route-list {
  display: grid;
  gap: 12px;
}

.route-card {
  display: flex;
  gap: 0;
  background: var(--bg-surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
}

.route-line {
  flex: 0 0 6px;
  background: var(--blue);
}

.route-body {
  min-width: 0;
  padding: 12px 16px;
}

.route-code {
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--ink-faint);
}

.route-name {
  font-size: 16px;
  margin: 2px 0 6px;
}

.route-scope {
  font-size: 14px;
  color: var(--ink-muted);
}

.route-dir {
  margin-top: 6px;
  font-size: 13px;
  color: var(--ink-faint);
}

.route-blue .route-line {
  background: var(--blue);
}

.route-green .route-line {
  background: var(--green);
}

.route-amber .route-line {
  background: var(--amber);
}

.route-purple .route-line {
  background: var(--purple);
}

.route-red .route-line {
  background: var(--red);
}

.section-figure img {
  width: 100%;
  height: 260px;
  object-fit: cover;
  border-radius: var(--radius);
  border: 1px solid var(--line);
  background: var(--bg-soft);
}

/* 首页 · 最新进展时间线 */
.timeline {
  display: grid;
  gap: 14px;
  border-left: 2px solid var(--line);
  padding-left: 18px;
}

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

.timeline-item::before {
  content: "";
  position: absolute;
  left: -25px;
  top: 20px;
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: var(--bg-surface);
  border: 2px solid var(--blue);
}

.timeline-date {
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--ink-faint);
}

.timeline-name {
  font-size: 16px;
  margin: 4px 0 6px;
}

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

.timeline-meta {
  margin-top: 8px;
}

/* 首页 · 本周专题片单速览 */
.special-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 16px;
}

.special-card {
  background: var(--bg-surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 16px;
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.special-name {
  font-size: 16px;
}

.special-name a {
  color: var(--ink);
}

.special-name a:hover {
  color: var(--blue);
}

.special-scope {
  font-size: 14px;
  color: var(--ink-muted);
}

.special-range {
  font-size: 13px;
  color: var(--ink-faint);
  font-family: var(--font-mono);
}

/* 首页 · 内容边界与反馈入口 */
.boundary-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.4fr) minmax(0, 1fr);
  gap: 24px;
  align-items: start;
}

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

.boundary-subtitle {
  font-size: 16px;
  margin-bottom: 8px;
}

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

.boundary-list {
  display: grid;
  gap: 8px;
  margin-top: 10px;
}

.boundary-item {
  font-size: 14px;
  color: var(--ink-muted);
  padding-left: 16px;
  position: relative;
}

.boundary-item::before {
  content: "";
  position: absolute;
  left: 0;
  top: 10px;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--line);
}

.boundary-links {
  margin-top: 12px;
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  font-size: 14px;
}

/* ==========================================================================
   pages —— 频道分类
   ========================================================================== */

.page-layout {
  display: grid;
  gap: 28px;
  align-items: start;
}

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

.filter-panel {
  background: var(--bg-surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 16px;
}

.panel-title {
  font-size: 16px;
  margin-bottom: 6px;
}

.panel-note {
  font-size: 13px;
  color: var(--ink-muted);
  margin-bottom: 14px;
}

.filter-group {
  padding-top: 12px;
  border-top: 1px solid var(--line-soft);
  margin-top: 12px;
}

.filter-group:first-of-type {
  border-top: none;
  margin-top: 0;
  padding-top: 0;
}

.filter-group-title {
  font-size: 14px;
  margin-bottom: 8px;
}

.filter-list {
  display: grid;
  gap: 4px;
}

.filter-link {
  display: inline-flex;
  align-items: center;
  min-height: 32px;
  padding: 4px 10px;
  font-size: 14px;
  color: var(--ink-muted);
  border-radius: var(--radius-sm);
  border: 1px solid transparent;
}

.filter-link:hover {
  background: var(--bg-page);
  color: var(--ink);
  text-decoration: none;
}

.filter-link.is-active {
  background: var(--bg-page);
  border-color: var(--blue);
  color: var(--blue);
  font-weight: 700;
}

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

.channel-figure img {
  width: 100%;
  height: 220px;
  object-fit: cover;
  border-radius: var(--radius);
  border: 1px solid var(--line);
  background: var(--bg-soft);
}

.line-card {
  background: var(--bg-surface);
  border: 1px solid var(--line);
  border-left: 5px solid var(--blue);
  border-radius: var(--radius);
  padding: 16px;
  margin-bottom: 14px;
}

.line-card:last-child {
  margin-bottom: 0;
}

.line-blue {
  border-left-color: var(--blue);
}

.line-green {
  border-left-color: var(--green);
}

.line-amber {
  border-left-color: var(--amber);
}

.line-purple {
  border-left-color: var(--purple);
}

.line-red {
  border-left-color: var(--red);
}

.line-card-head {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 8px;
}

.line-code {
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--ink-faint);
  border: 1px solid var(--line);
  border-radius: 10px;
  padding: 1px 8px;
}

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

.line-scope {
  font-size: 14px;
  color: var(--ink-muted);
}

.line-meta {
  margin: 12px 0 0;
  display: grid;
  grid-template-columns: minmax(88px, auto) minmax(0, 1fr);
  gap: 6px 14px;
  font-size: 14px;
}

.line-meta dt {
  color: var(--ink-faint);
  font-family: var(--font-mono);
  font-size: 13px;
}

.line-meta dd {
  margin: 0;
  color: var(--ink-muted);
}

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

.section-foot a {
  margin-right: 14px;
}

/* ==========================================================================
   pages —— 专题片单
   ========================================================================== */

.section-media img {
  width: 100%;
  height: 240px;
  object-fit: cover;
  border-radius: var(--radius);
  border: 1px solid var(--line);
  background: var(--bg-soft);
}

.media-caption {
  margin-top: 8px;
}

.topic-grid {
  margin-top: 20px;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 16px;
}

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

.topic-title {
  font-size: 17px;
  margin-bottom: 10px;
}

.topic-range,
.topic-time,
.topic-rep {
  font-size: 14px;
  color: var(--ink-muted);
  margin-bottom: 6px;
}

.topic-rep {
  margin-bottom: 0;
}

.topic-label {
  display: inline-block;
  min-width: 60px;
  color: var(--ink-faint);
  font-size: 13px;
}

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

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

.range-item-title {
  font-size: 16px;
  margin-bottom: 6px;
}

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

.relation-body {
  background: var(--bg-surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 16px;
}

.relation-text {
  font-size: 14px;
  color: var(--ink-muted);
  margin-bottom: 10px;
}

.relation-note {
  font-size: 13px;
  color: var(--ink-faint);
}

/* ==========================================================================
   pages —— 观看指引
   ========================================================================== */

.guide-media img {
  width: 100%;
  height: 230px;
  object-fit: cover;
  border-radius: var(--radius);
  border: 1px solid var(--line);
  background: var(--bg-soft);
  margin-top: 16px;
}

.guide-steps .step-list {
  margin-top: 20px;
}

.check-list {
  display: grid;
  gap: 12px;
}

.check-item {
  display: flex;
  gap: 14px;
  background: var(--bg-surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 14px 16px;
}

.check-index {
  flex: 0 0 auto;
  width: 26px;
  height: 26px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-sm);
  background: var(--bg-soft);
  color: var(--ink-muted);
  font-size: 13px;
  font-family: var(--font-mono);
}

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

.check-title {
  font-size: 16px;
  margin-bottom: 4px;
}

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

.faq-list {
  display: grid;
  gap: 10px;
}

.faq-item {
  background: var(--bg-surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 0 16px;
}

.faq-question {
  cursor: pointer;
  list-style: none;
  padding: 13px 24px 13px 0;
  font-size: 16px;
  font-weight: 700;
  position: relative;
}

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

.faq-question::after {
  content: "";
  position: absolute;
  right: 2px;
  top: 21px;
  width: 8px;
  height: 8px;
  border-right: 2px solid var(--ink-muted);
  border-bottom: 2px solid var(--ink-muted);
  transform: rotate(45deg);
}

.faq-item[open] .faq-question::after {
  transform: rotate(-135deg);
  top: 24px;
}

.faq-answer {
  padding: 12px 0 14px;
  font-size: 14px;
  color: var(--ink-muted);
  border-top: 1px solid var(--line-soft);
}

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

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

.feedback-title {
  font-size: 16px;
  margin-bottom: 6px;
}

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

.feedback-note {
  margin-top: 14px;
  font-size: 14px;
  color: var(--ink-muted);
}

/* ==========================================================================
   pages —— 变动记录
   ========================================================================== */

.page-layout.updates-layout {
  grid-template-columns: minmax(0, 1fr) minmax(0, 320px);
}

.updates-timeline {
  min-width: 0;
}

.timeline-group {
  margin-top: 22px;
}

.timeline-month {
  font-size: 16px;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--line);
  font-family: var(--font-mono);
}

.timeline-list {
  display: grid;
  gap: 12px;
  margin-top: 12px;
}

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

.timeline-time {
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--ink-faint);
  margin-bottom: 6px;
}

.updates-timeline .timeline-text {
  font-size: 14px;
  color: var(--ink-muted);
  margin-top: 6px;
}

.updates-types,
.updates-archive,
.updates-boundary {
  background: var(--bg-surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 16px;
  margin-bottom: 18px;
}

.type-list {
  margin: 0;
  display: grid;
  gap: 10px;
}

.type-item {
  padding-bottom: 10px;
  border-bottom: 1px solid var(--line-soft);
}

.type-item:last-child {
  border-bottom: none;
  padding-bottom: 0;
}

.type-name {
  font-size: 15px;
  font-weight: 700;
  font-family: var(--font-mono);
}

.type-desc {
  margin: 4px 0 0;
  font-size: 14px;
  color: var(--ink-muted);
}

.archive-list {
  display: grid;
  gap: 8px;
}

.archive-item a {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 12px;
  padding: 8px 10px;
  border: 1px solid var(--line-soft);
  border-radius: var(--radius-sm);
  font-size: 14px;
  color: var(--ink);
}

.archive-item a:hover {
  border-color: var(--blue);
  color: var(--blue);
  text-decoration: none;
}

.archive-period {
  font-family: var(--font-mono);
  font-weight: 700;
}

.archive-note {
  font-size: 13px;
  color: var(--ink-muted);
}

.updates-boundary .boundary-list {
  margin-top: 0;
}

/* ==========================================================================
   pages —— 404
   ========================================================================== */

.error-main {
  max-width: var(--wrap);
  margin: 0 auto;
  padding: 56px 20px 64px;
}

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

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

.error-title {
  font-size: 26px;
}

.error-text {
  margin-top: 12px;
  font-size: 15px;
  color: var(--ink-muted);
  max-width: 640px;
}

.error-actions {
  margin-top: 20px;
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

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

.error-hint-title {
  font-size: 18px;
  margin-bottom: 10px;
}

.error-hint-list {
  display: grid;
  gap: 8px;
}

.error-hint-list li {
  font-size: 14px;
  color: var(--ink-muted);
  padding-left: 16px;
  position: relative;
}

.error-hint-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 10px;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--line);
}

/* ==========================================================================
   responsive —— 断点 960px / 640px
   ========================================================================== */

@media (max-width: 960px) {
  .nav-toggle {
    display: inline-flex;
  }

  .site-nav {
    position: absolute;
    left: 0;
    right: 0;
    top: 100%;
    margin-left: 0;
  }

  .nav-list {
    display: none;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    background: var(--bg-surface);
    border-bottom: 1px solid var(--line);
    padding: 6px 20px 12px;
  }

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

  .nav-link {
    min-height: 44px;
    display: flex;
    align-items: center;
    border-bottom: 1px solid var(--line-soft);
  }

  .nav-link.is-current {
    border-bottom-color: var(--line-soft);
  }

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

  .hero-title {
    font-size: 26px;
  }

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

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

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

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

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

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

  .header-inner {
    padding: 0 14px;
    min-height: 58px;
  }

  .brand-slogan {
    display: none;
  }

  .inner-main {
    padding: 18px 14px 40px;
  }

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

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

  .hero-grid {
    padding: 22px 14px 24px;
  }

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

  .hero-figure img,
  .section-figure img,
  .section-media img,
  .channel-figure img,
  .guide-media img {
    height: 180px;
  }

  .hero-actions .btn {
    flex: 1 1 auto;
  }

  .special-grid,
  .topic-grid,
  .range-list,
  .feedback-list {
    grid-template-columns: minmax(0, 1fr);
  }

  .line-meta {
    grid-template-columns: minmax(0, 1fr);
    gap: 2px;
  }

  .line-meta dd {
    margin-bottom: 8px;
  }

  .timeline {
    padding-left: 14px;
  }

  .timeline-item::before {
    left: -21px;
  }

  .footer-inner {
    grid-template-columns: minmax(0, 1fr);
    padding: 24px 14px 8px;
    gap: 20px;
  }

  .footer-copy {
    padding: 12px 14px 20px;
  }

  .error-main {
    padding: 32px 14px 48px;
  }

  .error-panel {
    padding: 22px 18px;
  }

  .error-title {
    font-size: 21px;
  }
}