/* ==========================================================================
   吃瓜爆料 - 全站样式表
   版本: 1.0
   说明: 覆盖首页、内页、404页全部真实DOM
   ========================================================================== */

/* ==========================================================================
   Base - 基础变量与重置
   ========================================================================== */

:root {
  --color-white: #ffffff;
  --color-ink: #1a1a1a;
  --color-text: #333333;
  --color-muted: #666666;
  --color-accent: #c0392b;
  --color-accent-light: #e74c3c;
  --color-border: #e5e5e5;
  --color-bg-soft: #f7f7f5;
  --font-stack: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', sans-serif;
  --container-width: 1200px;
  --radius-sm: 4px;
  --radius-md: 6px;
  --radius-lg: 8px;
  --transition-fast: 0.2s ease;
  --transition-slow: 0.3s ease;
}

*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

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

body {
  font-family: var(--font-stack);
  font-size: 16px;
  line-height: 1.7;
  color: var(--color-text);
  background-color: var(--color-white);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

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

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

a:hover {
  color: var(--color-accent-light);
}

ul,
ol {
  list-style: none;
}

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

h1 {
  font-size: 2rem;
}

h2 {
  font-size: 1.5rem;
}

h3 {
  font-size: 1.125rem;
}

/* ==========================================================================
   Layout - 全站骨架
   ========================================================================== */

.site-header {
  background-color: var(--color-white);
  border-bottom: 1px solid var(--color-border);
  position: sticky;
  top: 0;
  z-index: 100;
}

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

.brand {
  display: flex;
  align-items: baseline;
  gap: 10px;
  flex-shrink: 0;
}

.brand-name {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--color-ink);
  letter-spacing: 0.02em;
}

.brand-slogan {
  font-size: 0.875rem;
  color: var(--color-muted);
  white-space: nowrap;
}

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

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

.nav-list li a {
  display: block;
  padding: 8px 16px;
  font-size: 0.9375rem;
  color: var(--color-text);
  border-radius: var(--radius-sm);
  transition: background-color var(--transition-fast), color var(--transition-fast);
}

.nav-list li a:hover {
  color: var(--color-accent);
  background-color: var(--color-bg-soft);
}

.nav-list li a.is-current {
  color: var(--color-accent);
  font-weight: 600;
  background-color: rgba(192, 57, 43, 0.08);
}

.nav-toggle {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: 8px;
  flex-direction: column;
  gap: 5px;
  align-items: center;
  justify-content: center;
}

.nav-toggle-bar {
  display: block;
  width: 24px;
  height: 2px;
  background-color: var(--color-ink);
  border-radius: 2px;
  transition: transform var(--transition-fast), opacity var(--transition-fast);
}

.site-main {
  flex: 1 0 auto;
}

.inner-main {
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 0 24px;
  width: 100%;
}

.site-footer {
  background-color: var(--color-bg-soft);
  border-top: 1px solid var(--color-border);
  margin-top: 64px;
  flex-shrink: 0;
}

.footer-inner {
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 48px 24px 24px;
}

.footer-brand {
  margin-bottom: 32px;
}

.footer-brand-name {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--color-ink);
  margin-bottom: 4px;
}

.footer-tagline {
  font-size: 0.875rem;
  color: var(--color-muted);
}

.footer-links {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 32px;
  padding-bottom: 32px;
  border-bottom: 1px solid var(--color-border);
}

.footer-col h3 {
  font-size: 0.9375rem;
  color: var(--color-ink);
  margin-bottom: 12px;
}

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

.footer-col ul li a {
  font-size: 0.875rem;
  color: var(--color-muted);
}

.footer-col ul li a:hover {
  color: var(--color-accent);
}

.footer-copyright {
  padding-top: 24px;
  font-size: 0.8125rem;
  color: var(--color-muted);
  text-align: center;
}

/* ==========================================================================
   Components - 通用组件
   ========================================================================== */

/* 面包屑 */
.breadcrumb {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 20px 0;
  font-size: 0.875rem;
  flex-wrap: wrap;
}

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

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

.breadcrumb-sep {
  color: #cccccc;
}

.breadcrumb-current {
  color: var(--color-text);
  font-weight: 500;
}

/* 页面标题区 */
.page-header {
  padding: 16px 0 32px;
  border-bottom: 1px solid var(--color-border);
  margin-bottom: 32px;
}

.page-title {
  font-size: 2rem;
  color: var(--color-ink);
  margin-bottom: 12px;
}

.page-description {
  font-size: 1rem;
  color: var(--color-muted);
  max-width: 720px;
  line-height: 1.7;
}

/* 布局壳 */
.layout-shell {
  display: flex;
  gap: 40px;
  align-items: flex-start;
}

.main-column,
.main-content {
  flex: 1 1 0;
  min-width: 0;
}

.side-column,
.sidebar {
  width: 340px;
  flex-shrink: 0;
}

/* 侧栏通用 */
.sidebar-block,
.hot-topics,
.aside-card {
  background-color: var(--color-bg-soft);
  border-radius: var(--radius-lg);
  padding: 24px;
  margin-bottom: 24px;
}

.sidebar-block h2,
.hot-topics h2,
.aside-card h2 {
  font-size: 1.125rem;
  margin-bottom: 16px;
  padding-bottom: 12px;
  border-bottom: 1px solid var(--color-border);
}

.sidebar-list li,
.topic-links li,
.aside-link-list li {
  margin-bottom: 12px;
  padding-left: 16px;
  position: relative;
}

.sidebar-list li::before,
.topic-links li::before,
.aside-link-list li::before {
  content: '';
  position: absolute;
  left: 0;
  top: 0.6em;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background-color: var(--color-accent);
}

.sidebar-list li a,
.topic-links li a,
.aside-link-list li a {
  font-size: 0.9375rem;
  color: var(--color-text);
  line-height: 1.5;
}

.sidebar-list li a:hover,
.topic-links li a:hover,
.aside-link-list li a:hover {
  color: var(--color-accent);
}

/* 按钮 */
.btn-primary,
.btn-secondary {
  display: inline-block;
  padding: 12px 28px;
  font-size: 0.9375rem;
  font-weight: 600;
  border-radius: var(--radius-md);
  transition: background-color var(--transition-fast), transform var(--transition-fast), box-shadow var(--transition-fast);
}

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

.btn-primary:hover {
  background-color: #a93226;
  color: var(--color-white);
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(192, 57, 43, 0.2);
}

.btn-secondary {
  background-color: transparent;
  color: var(--color-accent);
  border: 1px solid var(--color-accent);
}

.btn-secondary:hover {
  background-color: rgba(192, 57, 43, 0.06);
  transform: translateY(-2px);
}

/* 频道标签 */
.channel-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.channel-tags li a {
  display: inline-block;
  padding: 8px 20px;
  font-size: 0.9375rem;
  color: var(--color-text);
  background-color: var(--color-bg-soft);
  border: 1px solid var(--color-border);
  border-radius: 24px;
  transition: all var(--transition-fast);
}

.channel-tags li a:hover {
  color: var(--color-white);
  background-color: var(--color-accent);
  border-color: var(--color-accent);
}

/* 专题卡片 */
.topic-card {
  background-color: var(--color-white);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  overflow: hidden;
  transition: transform var(--transition-slow), box-shadow var(--transition-slow);
}

.topic-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 8px 24px rgba(0, 0, 0, 0.08);
}

.topic-card a {
  display: block;
  color: inherit;
}

.topic-card figure,
.topic-figure {
  aspect-ratio: 16 / 9;
  overflow: hidden;
  background-color: var(--color-bg-soft);
}

.topic-card figure img,
.topic-figure img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.topic-card h3 {
  padding: 16px 16px 8px;
  font-size: 1.0625rem;
}

.topic-card p {
  padding: 0 16px 16px;
  font-size: 0.875rem;
  color: var(--color-muted);
  line-height: 1.6;
}

/* ==========================================================================
   Pages - 首页
   ========================================================================== */

.home-main {
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 0 24px;
}

/* Hero 焦点区 */
.hero-section {
  display: grid;
  grid-template-columns: 1.1fr 0.9fr;
  gap: 48px;
  align-items: center;
  padding: 56px 0 48px;
}

.hero-content h1 {
  font-size: 2.25rem;
  line-height: 1.3;
  margin-bottom: 16px;
}

.hero-description {
  font-size: 1.0625rem;
  color: var(--color-muted);
  margin-bottom: 32px;
  line-height: 1.8;
  max-width: 520px;
}

.hero-actions {
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
}

.hero-media {
  aspect-ratio: 4 / 3;
  border-radius: var(--radius-lg);
  overflow: hidden;
  background-color: var(--color-bg-soft);
}

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

/* 频道导航带 */
.channel-nav-section {
  padding: 48px 0;
  border-top: 1px solid var(--color-border);
}

.channel-nav-section h2,
.latest-news-section h2,
.topics-section h2,
.recommend-section h2,
.source-feedback-section h2 {
  font-size: 1.5rem;
  margin-bottom: 8px;
}

.section-intro {
  font-size: 0.9375rem;
  color: var(--color-muted);
  margin-bottom: 24px;
  max-width: 640px;
}

.channel-nav-more {
  margin-top: 20px;
}

.channel-nav-more a,
.topics-more a {
  font-size: 0.9375rem;
  color: var(--color-accent);
  font-weight: 500;
}

/* 最新资讯 */
.latest-news-section {
  padding: 48px 0;
  border-top: 1px solid var(--color-border);
}

.news-group {
  margin-bottom: 32px;
}

.news-group h3 {
  font-size: 1.125rem;
  margin-bottom: 16px;
  padding-left: 12px;
  border-left: 4px solid var(--color-accent);
}

.news-list li {
  padding: 16px 0;
  border-bottom: 1px solid var(--color-border);
}

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

.news-list li a {
  display: grid;
  grid-template-columns: 1fr auto;
  grid-template-areas:
    "title date"
    "summary date";
  gap: 4px 24px;
  align-items: baseline;
}

.news-title {
  grid-area: title;
  font-size: 1rem;
  font-weight: 600;
  color: var(--color-ink);
  transition: color var(--transition-fast);
}

.news-summary {
  grid-area: summary;
  font-size: 0.875rem;
  color: var(--color-muted);
  line-height: 1.5;
}

.news-date {
  grid-area: date;
  font-size: 0.8125rem;
  color: #999999;
  white-space: nowrap;
}

.news-list li a:hover .news-title {
  color: var(--color-accent);
}

/* 专题策划 */
.topics-section {
  padding: 48px 0;
  border-top: 1px solid var(--color-border);
}

.topics-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 24px;
}

.topics-more {
  margin-top: 24px;
}

/* 编辑推荐 */
.recommend-section {
  padding: 48px 0;
  border-top: 1px solid var(--color-border);
}

.recommend-list li {
  padding: 20px 24px;
  background-color: var(--color-bg-soft);
  border-radius: var(--radius-md);
  margin-bottom: 16px;
  transition: transform var(--transition-fast), box-shadow var(--transition-fast);
}

.recommend-list li:hover {
  transform: translateY(-2px);
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.06);
}

.recommend-list li a {
  display: block;
}

.recommend-title {
  display: block;
  font-size: 1.0625rem;
  font-weight: 600;
  color: var(--color-ink);
  margin-bottom: 4px;
}

.recommend-reason {
  display: block;
  font-size: 0.875rem;
  color: var(--color-muted);
}

.recommend-list li a:hover .recommend-title {
  color: var(--color-accent);
}

/* 来源与反馈 */
.source-feedback-section {
  padding: 48px 0;
  border-top: 1px solid var(--color-border);
}

.source-block {
  background-color: var(--color-bg-soft);
  border-radius: var(--radius-lg);
  padding: 24px;
  margin-bottom: 20px;
}

.source-block p {
  font-size: 0.9375rem;
  color: var(--color-text);
  margin-bottom: 12px;
  line-height: 1.7;
}

.source-block p:last-child {
  margin-bottom: 0;
}

.feedback-link a {
  font-size: 0.9375rem;
  font-weight: 500;
}

/* ==========================================================================
   Pages - 频道分类 (channels)
   ========================================================================== */

.page-layout {
  display: flex;
  gap: 40px;
  align-items: flex-start;
}

.channel-list h2,
.channel-featured h2 {
  font-size: 1.25rem;
  margin-bottom: 24px;
  padding-bottom: 12px;
  border-bottom: 1px solid var(--color-border);
}

.channel-item {
  display: flex;
  gap: 24px;
  padding: 24px 0;
  border-bottom: 1px solid var(--color-border);
  align-items: flex-start;
}

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

.channel-media {
  width: 220px;
  aspect-ratio: 3 / 2;
  border-radius: var(--radius-md);
  overflow: hidden;
  background-color: var(--color-bg-soft);
  flex-shrink: 0;
}

.channel-media img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.channel-content {
  flex: 1;
  min-width: 0;
}

.channel-content h3 {
  font-size: 1.125rem;
  margin-bottom: 8px;
}

.channel-content p {
  font-size: 0.9375rem;
  color: var(--color-muted);
  margin-bottom: 12px;
  line-height: 1.7;
}

.channel-link {
  font-size: 0.875rem;
  font-weight: 500;
}

.channel-featured {
  margin-top: 40px;
}

.channel-featured > p {
  font-size: 0.9375rem;
  color: var(--color-muted);
  margin-bottom: 20px;
}

.featured-list li {
  padding: 16px 20px;
  background-color: var(--color-bg-soft);
  border-radius: var(--radius-md);
  margin-bottom: 12px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
}

.featured-list li a {
  font-size: 0.9375rem;
  color: var(--color-text);
  font-weight: 500;
  flex: 1;
}

.featured-list li a:hover {
  color: var(--color-accent);
}

.featured-list .tag {
  font-size: 0.75rem;
  color: var(--color-accent);
  background-color: rgba(192, 57, 43, 0.08);
  padding: 4px 12px;
  border-radius: 16px;
  flex-shrink: 0;
}

/* ==========================================================================
   Pages - 内容专题 (topics)
   ========================================================================== */

.topic-list h2,
.timeline-preview h2 {
  font-size: 1.25rem;
  margin-bottom: 24px;
  padding-bottom: 12px;
  border-bottom: 1px solid var(--color-border);
}

.topic-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 24px;
  margin-bottom: 48px;
}

.topic-card-link {
  display: block;
  color: inherit;
}

.topic-card-link:hover {
  color: inherit;
}

.topic-card .topic-figure {
  aspect-ratio: 16 / 9;
  overflow: hidden;
  background-color: var(--color-bg-soft);
}

.topic-card .topic-figure img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform var(--transition-slow);
}

.topic-card:hover .topic-figure img {
  transform: scale(1.03);
}

.topic-card h3 {
  padding: 16px 16px 8px;
  font-size: 1.0625rem;
}

.topic-card p {
  padding: 0 16px 16px;
  font-size: 0.875rem;
  color: var(--color-muted);
  line-height: 1.6;
}

.timeline-preview {
  margin-top: 40px;
}

.timeline-preview > p {
  font-size: 0.9375rem;
  color: var(--color-muted);
  margin-bottom: 24px;
}

.timeline-list {
  position: relative;
  padding-left: 24px;
}

.timeline-list::before {
  content: '';
  position: absolute;
  left: 6px;
  top: 8px;
  bottom: 8px;
  width: 2px;
  background-color: var(--color-border);
}

.timeline-item {
  position: relative;
  padding-bottom: 24px;
}

.timeline-item::before {
  content: '';
  position: absolute;
  left: -23px;
  top: 6px;
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background-color: var(--color-accent);
  border: 2px solid var(--color-white);
  box-shadow: 0 0 0 2px var(--color-accent);
}

.timeline-item h3 {
  font-size: 1rem;
  margin-bottom: 4px;
}

.timeline-item p {
  font-size: 0.875rem;
  color: var(--color-muted);
  line-height: 1.6;
}

/* ==========================================================================
   Pages - 热点解读 (hotspot)
   ========================================================================== */

.analysis-framework h2,
.case-analysis h2,
.related-reading h2 {
  font-size: 1.25rem;
  margin-bottom: 16px;
  padding-bottom: 12px;
  border-bottom: 1px solid var(--color-border);
}

.analysis-framework > p,
.case-analysis > p {
  font-size: 0.9375rem;
  color: var(--color-muted);
  margin-bottom: 24px;
  line-height: 1.7;
}

.framework-step {
  padding: 20px 24px;
  background-color: var(--color-bg-soft);
  border-radius: var(--radius-md);
  margin-bottom: 16px;
}

.framework-step h3 {
  font-size: 1.0625rem;
  margin-bottom: 8px;
  display: flex;
  align-items: center;
  gap: 8px;
}

.framework-step h3::before {
  content: '';
  display: inline-block;
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background-color: var(--color-accent);
  flex-shrink: 0;
}

.framework-step p {
  font-size: 0.9375rem;
  color: var(--color-text);
  line-height: 1.7;
}

.case-analysis {
  margin-top: 48px;
}

.case-figure {
  aspect-ratio: 16 / 9;
  border-radius: var(--radius-lg);
  overflow: hidden;
  background-color: var(--color-bg-soft);
  margin-bottom: 16px;
}

.case-figure img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.case-figure figcaption {
  font-size: 0.8125rem;
  color: var(--color-muted);
  padding: 12px 16px;
  background-color: var(--color-bg-soft);
}

.comparison-table-wrap {
  overflow-x: auto;
  margin: 24px 0;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
}

.comparison-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.9375rem;
  min-width: 560px;
}

.comparison-table caption {
  font-size: 0.9375rem;
  font-weight: 600;
  color: var(--color-ink);
  padding: 16px;
  text-align: left;
  background-color: var(--color-bg-soft);
  border-bottom: 1px solid var(--color-border);
}

.comparison-table thead th {
  background-color: var(--color-bg-soft);
  font-weight: 600;
  color: var(--color-ink);
  text-align: left;
  padding: 12px 16px;
  border-bottom: 2px solid var(--color-border);
}

.comparison-table tbody td {
  padding: 12px 16px;
  border-bottom: 1px solid var(--color-border);
  vertical-align: top;
  line-height: 1.6;
}

.comparison-table tbody tr:last-child td {
  border-bottom: none;
}

.comparison-table tbody tr:nth-child(even) {
  background-color: rgba(0, 0, 0, 0.02);
}

.related-reading {
  margin-top: 48px;
}

.related-list li {
  padding: 16px 20px;
  background-color: var(--color-bg-soft);
  border-radius: var(--radius-md);
  margin-bottom: 12px;
}

.related-list li a {
  font-size: 0.9375rem;
  color: var(--color-text);
  font-weight: 500;
  line-height: 1.5;
}

.related-list li a:hover {
  color: var(--color-accent);
}

/* ==========================================================================
   Pages - 阅读指南 (guide)
   ========================================================================== */

.guide-layout {
  display: flex;
  gap: 40px;
  align-items: flex-start;
}

.guide-main {
  flex: 1;
  min-width: 0;
}

.guide-aside {
  width: 340px;
  flex-shrink: 0;
}

.guide-section {
  margin-bottom: 48px;
}

.guide-section h2 {
  font-size: 1.25rem;
  margin-bottom: 16px;
  padding-bottom: 12px;
  border-bottom: 1px solid var(--color-border);
}

.guide-section > p {
  font-size: 0.9375rem;
  color: var(--color-muted);
  margin-bottom: 20px;
  line-height: 1.7;
}

.guide-column-list li {
  padding: 16px 20px;
  background-color: var(--color-bg-soft);
  border-radius: var(--radius-md);
  margin-bottom: 12px;
}

.guide-column-list li h3 {
  font-size: 1rem;
  margin-bottom: 4px;
}

.guide-column-list li p {
  font-size: 0.875rem;
  color: var(--color-muted);
  line-height: 1.6;
}

.guide-step-list {
  counter-reset: guide-step;
}

.guide-step-list li {
  position: relative;
  padding: 20px 20px 20px 72px;
  background-color: var(--color-bg-soft);
  border-radius: var(--radius-md);
  margin-bottom: 16px;
}

.guide-step-list li::before {
  counter-increment: guide-step;
  content: counter(guide-step);
  position: absolute;
  left: 20px;
  top: 20px;
  width: 36px;
  height: 36px;
  border-radius: 50%;
  background-color: var(--color-accent);
  color: var(--color-white);
  font-size: 1rem;
  font-weight: 600;
  display: flex;
  align-items: center;
  justify-content: center;
}

.guide-step-list li h3 {
  font-size: 1rem;
  margin-bottom: 4px;
}

.guide-step-list li p {
  font-size: 0.875rem;
  color: var(--color-muted);
  line-height: 1.6;
}

.guide-quality-list li {
  padding: 12px 16px;
  padding-left: 32px;
  position: relative;
  font-size: 0.9375rem;
  border-bottom: 1px solid var(--color-border);
}

.guide-quality-list li::before {
  content: '✓';
  position: absolute;
  left: 8px;
  color: var(--color-accent);
  font-weight: 600;
}

.guide-feedback-list li {
  padding: 12px 16px;
  padding-left: 32px;
  position: relative;
  font-size: 0.9375rem;
  border-bottom: 1px solid var(--color-border);
}

.guide-feedback-list li::before {
  content: '';
  position: absolute;
  left: 12px;
  top: 1.1em;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background-color: var(--color-accent);
}

.guide-related-list li {
  padding: 12px 0;
  border-bottom: 1px solid var(--color-border);
}

.guide-related-list li a {
  font-size: 0.9375rem;
  color: var(--color-text);
}

.guide-related-list li a:hover {
  color: var(--color-accent);
}

.aside-card {
  margin-bottom: 24px;
}

.guide-figure {
  aspect-ratio: 16 / 10;
  border-radius: var(--radius-lg);
  overflow: hidden;
  background-color: var(--color-bg-soft);
}

.guide-figure img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.guide-figure figcaption {
  font-size: 0.8125rem;
  color: var(--color-muted);
  padding: 12px 16px;
  background-color: var(--color-bg-soft);
}

/* ==========================================================================
   Pages - 404
   ========================================================================== */

.error-main {
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 80px 24px;
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 60vh;
}

.error-content {
  text-align: center;
  max-width: 480px;
}

.error-code {
  font-size: 5rem;
  font-weight: 700;
  color: var(--color-accent);
  line-height: 1;
  margin-bottom: 16px;
}

.error-content h1 {
  font-size: 1.5rem;
  margin-bottom: 16px;
}

.error-desc {
  font-size: 0.9375rem;
  color: var(--color-muted);
  margin-bottom: 32px;
  line-height: 1.7;
}

.error-action {
  display: inline-block;
  padding: 12px 32px;
  background-color: var(--color-accent);
  color: var(--color-white);
  font-size: 0.9375rem;
  font-weight: 600;
  border-radius: var(--radius-md);
  transition: background-color var(--transition-fast), transform var(--transition-fast);
}

.error-action:hover {
  background-color: #a93226;
  color: var(--color-white);
  transform: translateY(-2px);
}

/* ==========================================================================
   Responsive - 响应式
   ========================================================================== */

@media (max-width: 1024px) {
  .hero-section {
    gap: 32px;
  }

  .hero-content h1 {
    font-size: 1.875rem;
  }

  .layout-shell,
  .page-layout {
    gap: 24px;
  }

  .side-column,
  .sidebar {
    width: 300px;
  }

  .guide-aside {
    width: 300px;
  }
}

@media (max-width: 768px) {
  .header-inner {
    height: 60px;
    padding: 0 16px;
  }

  .brand-slogan {
    display: none;
  }

  .nav-toggle {
    display: flex;
    margin-left: auto;
  }

  .site-nav {
    position: fixed;
    top: 60px;
    left: 0;
    right: 0;
    background-color: var(--color-white);
    border-bottom: 1px solid var(--color-border);
    box-shadow: 0 8px 24px rgba(0, 0, 0, 0.08);
    margin-left: 0;
    opacity: 0;
    visibility: hidden;
    transform: translateY(-8px);
    transition: opacity var(--transition-fast), transform var(--transition-fast), visibility var(--transition-fast);
    z-index: 99;
  }

  .nav-list {
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    padding: 8px 16px;
  }

  .nav-list li a {
    padding: 14px 16px;
    border-radius: var(--radius-sm);
  }

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

  .site-nav.is-open {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
  }

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

  .hero-section {
    grid-template-columns: 1fr;
    padding: 32px 0;
    gap: 24px;
  }

  .hero-content h1 {
    font-size: 1.625rem;
  }

  .hero-media {
    aspect-ratio: 16 / 10;
  }

  .channel-nav-section,
  .latest-news-section,
  .topics-section,
  .recommend-section,
  .source-feedback-section {
    padding: 32px 0;
  }

  .topics-grid,
  .topic-grid {
    grid-template-columns: 1fr;
  }

  .layout-shell,
  .page-layout,
  .guide-layout {
    flex-direction: column;
  }

  .main-column,
  .main-content,
  .guide-main {
    width: 100%;
    flex: none;
  }

  .side-column,
  .sidebar,
  .guide-aside {
    width: 100%;
    flex: none;
  }

  .channel-item {
    flex-direction: column;
    gap: 16px;
  }

  .channel-media {
    width: 100%;
    aspect-ratio: 16 / 9;
  }

  .news-list li a {
    grid-template-columns: 1fr;
    grid-template-areas:
      "title"
      "summary"
      "date";
    gap: 4px;
  }

  .news-date {
    margin-top: 4px;
  }

  .footer-inner {
    padding: 32px 16px 16px;
  }

  .footer-links {
    grid-template-columns: 1fr;
    gap: 24px;
  }

  .timeline-list {
    padding-left: 20px;
  }

  .timeline-item::before {
    left: -19px;
  }

  .guide-step-list li {
    padding: 16px 16px 16px 60px;
  }

  .guide-step-list li::before {
    left: 16px;
    width: 32px;
    height: 32px;
    font-size: 0.875rem;
  }

  .error-main {
    padding: 48px 16px;
  }

  .error-code {
    font-size: 3.5rem;
  }
}

@media (max-width: 480px) {
  .hero-actions {
    flex-direction: column;
    gap: 12px;
  }

  .btn-primary,
  .btn-secondary {
    width: 100%;
    text-align: center;
  }

  .channel-tags {
    gap: 8px;
  }

  .channel-tags li a {
    padding: 6px 16px;
    font-size: 0.875rem;
  }

  .featured-list li {
    flex-direction: column;
    align-items: flex-start;
    gap: 8px;
  }

  .page-header {
    padding: 12px 0 24px;
    margin-bottom: 24px;
  }

  .page-title {
    font-size: 1.625rem;
  }

  .breadcrumb {
    padding: 16px 0;
    font-size: 0.8125rem;
  }

  .comparison-table {
    font-size: 0.875rem;
    min-width: 480px;
  }

  .comparison-table thead th,
  .comparison-table tbody td {
    padding: 10px 12px;
  }

  .framework-step {
    padding: 16px;
  }
}

/* 滚动出现动画（增强，不影响初始可见性） */
@media (prefers-reduced-motion: no-preference) {
  .topic-card,
  .channel-item,
  .news-group,
  .recommend-list li,
  .framework-step,
  .timeline-item {
    will-change: opacity, transform;
  }
}