/* ============================================================
   BASE
   ============================================================ */
:root {
  --color-primary: #2c3e50;
  --color-accent: #e74c3c;
  --color-bg: #ecf0f1;
  --color-card: #ffffff;
  --color-text: #2c3e50;
  --color-text-secondary: #7f8c8d;
  --color-border: #dce1e5;
  --color-primary-light: #3d566e;
  --color-accent-dark: #c0392b;
  --color-accent-light: #fdecea;
  --font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
  --container-width: 1200px;
  --container-padding: 0 24px;
  --header-height: 64px;
  --radius-sm: 4px;
  --radius-md: 8px;
  --radius-lg: 8px;
  --transition-fast: 0.2s ease;
  --transition-normal: 0.3s ease;
  --shadow-sm: 0 1px 3px rgba(44, 62, 80, 0.08);
  --shadow-md: 0 2px 8px rgba(44, 62, 80, 0.1);
  --font-size-h1: 28px;
  --font-size-h2: 22px;
  --font-size-h3: 18px;
  --font-size-body: 16px;
}

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

html {
  font-size: var(--font-size-body);
  -webkit-text-size-adjust: 100%;
  scroll-behavior: smooth;
}

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

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

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

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

ul,
ol {
  list-style-position: inside;
}

h1,
h2,
h3,
h4,
h5,
h6 {
  font-weight: 700;
  line-height: 1.4;
  color: var(--color-text);
}

h1 {
  font-size: var(--font-size-h1);
}

h2 {
  font-size: var(--font-size-h2);
}

h3 {
  font-size: var(--font-size-h3);
}

p {
  margin-bottom: 12px;
}

/* ============================================================
   LAYOUT - 全站统一外壳
   ============================================================ */

/* 站点主体容器 */
.site-body {
  display: flex;
  flex-direction: column;
  min-height: 100vh;
}

.site-main {
  flex: 1 0 auto;
  width: 100%;
}

/* 统一内页容器宽度 */
.inner-main {
  width: 100%;
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 32px 24px 56px;
}

/* 首页主容器 */
.home-main {
  width: 100%;
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 0 24px 56px;
}

/* ============================================================
   HEADER - 全站统一页头
   ============================================================ */

.site-header {
  background-color: var(--color-primary);
  border-bottom: 3px solid var(--color-accent);
  position: sticky;
  top: 0;
  z-index: 100;
  box-shadow: var(--shadow-sm);
}

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

.brand {
  flex-shrink: 0;
}

.brand a {
  display: flex;
  flex-direction: column;
  line-height: 1.2;
}

.brand-name {
  font-size: 22px;
  font-weight: 700;
  color: #ffffff;
  letter-spacing: 1px;
}

.brand-tagline {
  font-size: 12px;
  color: rgba(255, 255, 255, 0.7);
  letter-spacing: 2px;
}

.brand a:hover .brand-name {
  color: #ffffff;
}

/* 主导航 */
.site-nav {
  display: flex;
  align-items: center;
}

.nav-list {
  display: flex;
  list-style: none;
  gap: 4px;
}

.nav-list li {
  margin: 0;
}

.nav-list a {
  display: block;
  padding: 8px 18px;
  color: rgba(255, 255, 255, 0.85);
  font-size: 15px;
  font-weight: 500;
  border-radius: var(--radius-sm);
  transition: background-color var(--transition-fast), color var(--transition-fast);
}

.nav-list a:hover {
  color: #ffffff;
  background-color: rgba(255, 255, 255, 0.12);
}

.nav-list a.is-current {
  color: #ffffff;
  background-color: var(--color-accent);
  font-weight: 600;
}

/* 汉堡按钮 - 桌面隐藏 */
.nav-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 44px;
  height: 44px;
  padding: 10px;
  background: transparent;
  border: 1px solid rgba(255, 255, 255, 0.3);
  border-radius: var(--radius-sm);
  cursor: pointer;
}

.nav-toggle-bar {
  display: block;
  width: 100%;
  height: 2px;
  background-color: #ffffff;
  border-radius: 2px;
  transition: transform var(--transition-fast), opacity var(--transition-fast);
}

/* ============================================================
   FOOTER - 全站统一页脚
   ============================================================ */

.site-footer {
  background-color: var(--color-primary);
  color: rgba(255, 255, 255, 0.8);
  margin-top: auto;
  flex-shrink: 0;
}

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

.footer-brand p {
  font-size: 15px;
  color: rgba(255, 255, 255, 0.6);
  margin-bottom: 32px;
  max-width: 420px;
}

.footer-brand strong {
  color: #ffffff;
  font-size: 18px;
  display: block;
  margin-bottom: 8px;
}

.footer-links {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 32px;
  padding-bottom: 32px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.15);
}

.footer-col h4 {
  color: #ffffff;
  font-size: 15px;
  font-weight: 600;
  margin-bottom: 16px;
}

.footer-col ul {
  list-style: none;
}

.footer-col li {
  margin-bottom: 10px;
}

.footer-col a {
  color: rgba(255, 255, 255, 0.7);
  font-size: 14px;
}

.footer-col a:hover {
  color: #ffffff;
}

.footer-bottom {
  padding-top: 24px;
  text-align: center;
}

.footer-bottom p {
  font-size: 13px;
  color: rgba(255, 255, 255, 0.5);
  margin: 0;
}

/* ============================================================
   COMPONENTS - 通用组件
   ============================================================ */

/* 面包屑 */
.breadcrumb {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 8px;
  font-size: 14px;
  color: var(--color-text-secondary);
  margin-bottom: 24px;
}

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

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

.breadcrumb-sep {
  color: #bdc3c7;
}

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

/* 页面标题区 */
.page-header {
  margin-bottom: 32px;
  padding-bottom: 24px;
  border-bottom: 1px solid var(--color-border);
}

.page-title {
  font-size: var(--font-size-h1);
  font-weight: 700;
  color: var(--color-text);
  margin-bottom: 12px;
}

.page-description {
  font-size: 16px;
  color: var(--color-text-secondary);
  line-height: 1.8;
  max-width: 720px;
}

/* 区块标题 */
.section-heading {
  margin-bottom: 28px;
}

.section-heading h2 {
  font-size: var(--font-size-h2);
  color: var(--color-text);
  margin-bottom: 8px;
  position: relative;
  padding-left: 14px;
}

.section-heading h2::before {
  content: "";
  position: absolute;
  left: 0;
  top: 4px;
  bottom: 4px;
  width: 4px;
  background-color: var(--color-accent);
  border-radius: 2px;
}

.section-heading p {
  color: var(--color-text-secondary);
  font-size: 15px;
  margin: 0;
}

.section-more-link {
  margin-top: 20px;
  text-align: right;
}

.section-more-link a {
  display: inline-block;
  font-size: 14px;
  font-weight: 500;
  color: var(--color-accent);
  padding: 6px 16px;
  border: 1px solid var(--color-accent);
  border-radius: var(--radius-sm);
  transition: background-color var(--transition-fast), color var(--transition-fast);
}

.section-more-link a:hover {
  background-color: var(--color-accent);
  color: #ffffff;
}

/* 按钮 */
.btn-primary,
.btn-secondary {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 44px;
  padding: 10px 24px;
  font-size: 15px;
  font-weight: 600;
  border-radius: var(--radius-sm);
  transition: background-color var(--transition-fast), color var(--transition-fast), border-color var(--transition-fast);
}

.btn-primary {
  background-color: var(--color-accent);
  color: #ffffff;
  border: 1px solid var(--color-accent);
}

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

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

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

/* 侧栏卡片 */
.sidebar-card {
  background-color: var(--color-card);
  border-radius: var(--radius-md);
  padding: 24px;
  box-shadow: var(--shadow-sm);
  margin-bottom: 24px;
}

.sidebar-card h2,
.sidebar-card h3 {
  font-size: 17px;
  font-weight: 600;
  margin-bottom: 16px;
  padding-bottom: 12px;
  border-bottom: 2px solid var(--color-accent);
}

.sidebar-card ul {
  list-style: none;
}

.sidebar-card li {
  margin-bottom: 12px;
}

.sidebar-card a {
  font-size: 14px;
  line-height: 1.6;
  display: inline-block;
}

/* 时间线组件（通用） */
.timeline-item {
  position: relative;
}

/* 来源说明 */
.source-note {
  background-color: var(--color-card);
  border-radius: var(--radius-md);
  padding: 28px;
  box-shadow: var(--shadow-sm);
  border-left: 4px solid var(--color-accent);
}

.source-note p {
  font-size: 14px;
  color: var(--color-text-secondary);
  margin-bottom: 8px;
  line-height: 1.8;
}

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

/* ============================================================
   PAGES - 首页
   ============================================================ */

/* Hero 首屏 */
.hero-section {
  padding: 56px 0 48px;
}

.hero-wrapper {
  display: grid;
  grid-template-columns: 1.1fr 0.9fr;
  gap: 48px;
  align-items: center;
}

.hero-copy h1 {
  font-size: 34px;
  font-weight: 700;
  line-height: 1.35;
  margin-bottom: 16px;
  color: var(--color-text);
}

.hero-copy > p {
  font-size: 16px;
  color: var(--color-text-secondary);
  line-height: 1.9;
  margin-bottom: 28px;
  max-width: 520px;
}

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

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

.hero-figure {
  margin: 0;
  border-radius: var(--radius-md);
  overflow: hidden;
  box-shadow: var(--shadow-md);
  background-color: var(--color-card);
}

.hero-figure img {
  width: 100%;
  height: 340px;
  object-fit: cover;
}

/* 首页内容区块 */
.section-block {
  margin-bottom: 48px;
}

/* 年度概览 - 首页时间线预览 */
.timeline-preview {
  background-color: var(--color-card);
  border-radius: var(--radius-md);
  padding: 24px 28px;
  box-shadow: var(--shadow-sm);
}

.timeline-preview .timeline-item {
  display: grid;
  grid-template-columns: 110px 1fr auto;
  gap: 16px;
  align-items: center;
  padding: 16px 0;
  border-bottom: 1px solid var(--color-border);
}

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

.timeline-preview .timeline-item:first-child {
  padding-top: 0;
}

.timeline-date {
  font-size: 14px;
  font-weight: 600;
  color: var(--color-accent);
  font-variant-numeric: tabular-nums;
}

.timeline-event {
  font-size: 15px;
  font-weight: 500;
  color: var(--color-text);
}

.timeline-status {
  font-size: 12px;
  padding: 4px 12px;
  border-radius: 20px;
  font-weight: 500;
  white-space: nowrap;
  background-color: var(--color-bg);
  color: var(--color-text-secondary);
}

/* 最新资讯 */
.news-list {
  display: grid;
  gap: 0;
}

.news-item {
  background-color: var(--color-card);
  border-radius: var(--radius-md);
  padding: 24px 28px;
  box-shadow: var(--shadow-sm);
  margin-bottom: 16px;
  transition: box-shadow var(--transition-fast), transform var(--transition-fast);
}

.news-item:hover {
  box-shadow: var(--shadow-md);
  transform: translateY(-2px);
}

.news-item h3 {
  font-size: 18px;
  font-weight: 600;
  margin-bottom: 8px;
}

.news-item h3 a {
  color: var(--color-text);
}

.news-item h3 a:hover {
  color: var(--color-accent);
}

.news-summary {
  font-size: 14px;
  color: var(--color-text-secondary);
  line-height: 1.7;
  margin-bottom: 12px;
}

.news-date {
  font-size: 13px;
  color: var(--color-text-secondary);
  font-variant-numeric: tabular-nums;
}

/* 专题推荐 - 首页两卡片 */
.topic-cards {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 24px;
}

.topic-cards .topic-card {
  background-color: var(--color-card);
  border-radius: var(--radius-md);
  overflow: hidden;
  box-shadow: var(--shadow-sm);
  transition: box-shadow var(--transition-fast), transform var(--transition-fast);
  display: flex;
  flex-direction: column;
}

.topic-cards .topic-card:hover {
  box-shadow: var(--shadow-md);
  transform: translateY(-3px);
}

.topic-cards .topic-card img {
  width: 100%;
  height: 200px;
  object-fit: cover;
}

.topic-cards .topic-card h3 {
  font-size: 19px;
  font-weight: 600;
  padding: 20px 24px 8px;
}

.topic-cards .topic-card h3 a {
  color: var(--color-text);
}

.topic-cards .topic-card h3 a:hover {
  color: var(--color-accent);
}

.topic-cards .topic-card p {
  font-size: 14px;
  color: var(--color-text-secondary);
  line-height: 1.7;
  padding: 0 24px 24px;
  margin: 0;
  flex-grow: 1;
}

/* 编辑推荐 */
.pick-list {
  display: grid;
  gap: 16px;
}

.pick-item {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 20px;
  align-items: start;
  background-color: var(--color-card);
  border-radius: var(--radius-md);
  padding: 20px 24px;
  box-shadow: var(--shadow-sm);
}

.pick-tag {
  font-size: 12px;
  font-weight: 600;
  color: var(--color-accent);
  background-color: var(--color-accent-light);
  padding: 4px 12px;
  border-radius: 20px;
  white-space: nowrap;
  margin-top: 2px;
}

.pick-item h3 {
  font-size: 17px;
  font-weight: 600;
  margin-bottom: 6px;
}

.pick-item h3 a {
  color: var(--color-text);
}

.pick-item h3 a:hover {
  color: var(--color-accent);
}

.pick-item p {
  font-size: 14px;
  color: var(--color-text-secondary);
  line-height: 1.7;
  margin: 0;
}

/* ============================================================
   PAGES - 内页统一布局
   ============================================================ */

/* 通用两栏布局：主内容 + 右侧栏 */
.page-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 320px;
  gap: 32px;
  align-items: start;
}

.page-layout .main-content {
  min-width: 0;
  min-width: 520px;
}

.page-layout .sidebar,
.page-layout .topic-sidebar,
.page-layout .sidebar-area {
  position: sticky;
  top: calc(var(--header-height) + 24px);
}

/* 侧栏在左的布局（channels 页） */
.sidebar-left .page-layout {
  grid-template-columns: 320px minmax(0, 1fr);
}

.sidebar-left .page-layout .content-area {
  min-width: 0;
  min-width: 520px;
}

.sidebar-left .page-layout .sidebar {
  order: 1;
  grid-column: 1;
  grid-row: 1;
}

.sidebar-left .page-layout .content-area {
  order: 2;
  grid-column: 2;
  grid-row: 1;
}

/* ============================================================
   PAGES - 频道分类页
   ============================================================ */

.sidebar-section {
  background-color: var(--color-card);
  border-radius: var(--radius-md);
  padding: 24px;
  box-shadow: var(--shadow-sm);
  margin-bottom: 24px;
}

.sidebar-section h2 {
  font-size: 17px;
  font-weight: 600;
  margin-bottom: 16px;
  padding-bottom: 12px;
  border-bottom: 2px solid var(--color-accent);
}

.sidebar-section p {
  font-size: 14px;
  color: var(--color-text-secondary);
  line-height: 1.8;
  margin-bottom: 12px;
}

.sidebar-section p:last-child {
  margin-bottom: 0;
}

.channel-list-section {
  background-color: var(--color-card);
  border-radius: var(--radius-md);
  padding: 28px;
  box-shadow: var(--shadow-sm);
  margin-bottom: 24px;
}

.channel-list-section h2 {
  font-size: 20px;
  font-weight: 600;
  margin-bottom: 24px;
  padding-bottom: 16px;
  border-bottom: 2px solid var(--color-accent);
}

.channel-list {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 16px;
}

.channel-item {
  display: flex;
  gap: 16px;
  align-items: flex-start;
  padding: 20px;
  background-color: var(--color-bg);
  border-radius: var(--radius-sm);
  transition: background-color var(--transition-fast);
}

.channel-item:hover {
  background-color: #e2e8ed;
}

.channel-media {
  flex-shrink: 0;
  width: 48px;
  height: 48px;
  border-radius: var(--radius-sm);
  background-color: var(--color-primary);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 20px;
  font-weight: 700;
  color: #ffffff;
}

.channel-info h3 {
  font-size: 16px;
  font-weight: 600;
  margin-bottom: 6px;
}

.channel-info p {
  font-size: 13px;
  color: var(--color-text-secondary);
  line-height: 1.6;
  margin: 0;
}

.channel-tips {
  background-color: var(--color-card);
  border-radius: var(--radius-md);
  padding: 28px;
  box-shadow: var(--shadow-sm);
}

.channel-tips h2 {
  font-size: 20px;
  font-weight: 600;
  margin-bottom: 16px;
  padding-bottom: 16px;
  border-bottom: 2px solid var(--color-accent);
}

.channel-tips p {
  font-size: 15px;
  color: var(--color-text-secondary);
  line-height: 1.8;
  margin-bottom: 12px;
}

.channel-tips a {
  color: var(--color-accent);
  font-weight: 500;
}

/* ============================================================
   PAGES - 内容专题页
   ============================================================ */

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

.topic-section h2,
.topic-highlights h2 {
  font-size: 20px;
  font-weight: 600;
  margin-bottom: 8px;
}

.section-intro {
  font-size: 15px;
  color: var(--color-text-secondary);
  margin-bottom: 24px;
}

.topic-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 24px;
}

.topic-grid .topic-card {
  background-color: var(--color-card);
  border-radius: var(--radius-md);
  overflow: hidden;
  box-shadow: var(--shadow-sm);
  transition: box-shadow var(--transition-fast), transform var(--transition-fast);
}

.topic-grid .topic-card:hover {
  box-shadow: var(--shadow-md);
  transform: translateY(-3px);
}

.topic-media {
  margin: 0;
  overflow: hidden;
}

.topic-media img {
  width: 100%;
  height: 180px;
  object-fit: cover;
}

.topic-card-body {
  padding: 20px 24px 24px;
}

.topic-card-body h3 {
  font-size: 17px;
  font-weight: 600;
  margin-bottom: 8px;
}

.topic-card-body h3 a {
  color: var(--color-text);
}

.topic-card-body h3 a:hover {
  color: var(--color-accent);
}

.topic-card-body p {
  font-size: 14px;
  color: var(--color-text-secondary);
  line-height: 1.7;
  margin: 0;
}

.topic-tag {
  display: inline-block;
  font-size: 12px;
  color: var(--color-accent);
  background-color: var(--color-accent-light);
  padding: 3px 10px;
  border-radius: 20px;
  margin-bottom: 10px;
}

.topic-highlights {
  margin-bottom: 48px;
}

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

.highlight-item {
  display: grid;
  grid-template-columns: 48px 1fr;
  gap: 16px;
  align-items: start;
  background-color: var(--color-card);
  border-radius: var(--radius-md);
  padding: 20px 24px;
  box-shadow: var(--shadow-sm);
}

.highlight-num {
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background-color: var(--color-accent);
  color: #ffffff;
  font-size: 16px;
  font-weight: 700;
  display: flex;
  align-items: center;
  justify-content: center;
}

.highlight-content h3 {
  font-size: 16px;
  font-weight: 600;
  margin-bottom: 6px;
}

.highlight-content p {
  font-size: 14px;
  color: var(--color-text-secondary);
  line-height: 1.7;
  margin: 0;
}

.related-links {
  background-color: var(--color-card);
  border-radius: var(--radius-md);
  padding: 24px;
  box-shadow: var(--shadow-sm);
  margin-top: 48px;
}

.related-links h2 {
  font-size: 17px;
  font-weight: 600;
  margin-bottom: 16px;
  padding-bottom: 12px;
  border-bottom: 2px solid var(--color-accent);
}

.related-links ul {
  list-style: none;
}

.related-links li {
  margin-bottom: 10px;
}

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

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

/* 专题侧栏 */
.topic-sidebar .sidebar-card h3 {
  font-size: 16px;
}

.topic-sidebar .sidebar-card li {
  padding-left: 12px;
  position: relative;
}

.topic-sidebar .sidebar-card li::before {
  content: "›";
  position: absolute;
  left: 0;
  color: var(--color-accent);
  font-weight: 700;
}

/* ============================================================
   PAGES - 实用指南页
   ============================================================ */

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

.guide-list h2,
.method-steps h2,
.background-analysis h2,
.timeline-tips h2,
.multi-perspective h2,
.source-feedback h2 {
  font-size: 20px;
  font-weight: 600;
  margin-bottom: 16px;
  padding-bottom: 12px;
  border-bottom: 2px solid var(--color-accent);
}

.content-media {
  margin: 24px 0;
  border-radius: var(--radius-md);
  overflow: hidden;
  box-shadow: var(--shadow-sm);
}

.content-media-inline {
  float: left;
  margin: 4px 24px 16px 0;
  width: 320px;
}

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

.content-media figcaption {
  background-color: var(--color-card);
  padding: 10px 16px;
  font-size: 13px;
  color: var(--color-text-secondary);
  text-align: center;
}

.guide-list > p {
  font-size: 15px;
  color: var(--color-text-secondary);
  line-height: 1.8;
  margin-bottom: 24px;
}

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

.guide-card {
  background-color: var(--color-card);
  border-radius: var(--radius-md);
  padding: 24px;
  box-shadow: var(--shadow-sm);
  transition: box-shadow var(--transition-fast), transform var(--transition-fast);
}

.guide-card:hover {
  box-shadow: var(--shadow-md);
  transform: translateY(-2px);
}

.guide-card h3 {
  font-size: 16px;
  font-weight: 600;
  margin-bottom: 8px;
}

.guide-card p {
  font-size: 14px;
  color: var(--color-text-secondary);
  line-height: 1.7;
  margin-bottom: 12px;
}

.guide-card a {
  font-size: 14px;
  font-weight: 500;
  color: var(--color-accent);
  display: inline-block;
}

.method-steps {
  margin-bottom: 48px;
}

.method-steps > p {
  font-size: 15px;
  color: var(--color-text-secondary);
  margin-bottom: 24px;
}

.steps-list {
  list-style: none;
  counter-reset: step-counter;
  display: grid;
  gap: 16px;
}

.steps-list li {
  counter-increment: step-counter;
  background-color: var(--color-card);
  border-radius: var(--radius-md);
  padding: 20px 24px 20px 64px;
  position: relative;
  box-shadow: var(--shadow-sm);
}

.steps-list li::before {
  content: counter(step-counter);
  position: absolute;
  left: 20px;
  top: 20px;
  width: 32px;
  height: 32px;
  border-radius: 50%;
  background-color: var(--color-accent);
  color: #ffffff;
  font-size: 15px;
  font-weight: 700;
  display: flex;
  align-items: center;
  justify-content: center;
}

.steps-list h3 {
  font-size: 16px;
  font-weight: 600;
  margin-bottom: 6px;
}

.steps-list p {
  font-size: 14px;
  color: var(--color-text-secondary);
  line-height: 1.7;
  margin: 0;
}

.background-analysis {
  margin-bottom: 48px;
}

.background-analysis > p {
  font-size: 15px;
  color: var(--color-text-secondary);
  line-height: 1.8;
  margin-bottom: 16px;
}

.background-analysis ul {
  list-style: none;
  margin-bottom: 16px;
}

.background-analysis li {
  background-color: var(--color-card);
  border-radius: var(--radius-sm);
  padding: 16px 20px;
  margin-bottom: 12px;
  font-size: 14px;
  color: var(--color-text-secondary);
  line-height: 1.7;
  box-shadow: var(--shadow-sm);
}

.background-analysis li strong {
  color: var(--color-text);
  display: block;
  margin-bottom: 4px;
}

.background-analysis > p a {
  color: var(--color-accent);
  font-weight: 500;
}

.timeline-tips {
  margin-bottom: 48px;
}

.timeline-tips > p {
  font-size: 15px;
  color: var(--color-text-secondary);
  margin-bottom: 20px;
}

.timeline-table {
  width: 100%;
  border-collapse: collapse;
  background-color: var(--color-card);
  border-radius: var(--radius-md);
  overflow: hidden;
  box-shadow: var(--shadow-sm);
  margin-bottom: 16px;
}

.timeline-table thead {
  background-color: var(--color-primary);
}

.timeline-table th {
  color: #ffffff;
  font-size: 14px;
  font-weight: 600;
  text-align: left;
  padding: 14px 20px;
}

.timeline-table td {
  padding: 14px 20px;
  font-size: 14px;
  border-bottom: 1px solid var(--color-border);
  color: var(--color-text);
}

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

.timeline-table tbody tr:nth-child(even) {
  background-color: #f8f9fa;
}

.timeline-tips > p:last-child a {
  color: var(--color-accent);
  font-weight: 500;
}

.multi-perspective {
  margin-bottom: 48px;
}

.multi-perspective > p {
  font-size: 15px;
  color: var(--color-text-secondary);
  margin-bottom: 20px;
}

.comparison-box {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 20px;
  margin-bottom: 16px;
}

.comparison-item {
  background-color: var(--color-card);
  border-radius: var(--radius-md);
  padding: 24px;
  box-shadow: var(--shadow-sm);
}

.comparison-item h3 {
  font-size: 16px;
  font-weight: 600;
  margin-bottom: 12px;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--color-border);
}

.comparison-item p {
  font-size: 14px;
  color: var(--color-text-secondary);
  line-height: 1.7;
  margin-bottom: 8px;
}

.multi-perspective > p:last-child a {
  color: var(--color-accent);
  font-weight: 500;
}

/* 指南页来源说明 */
.guide-page .source-feedback {
  background-color: var(--color-card);
  border-radius: var(--radius-md);
  padding: 28px;
  box-shadow: var(--shadow-sm);
  border-left: 4px solid var(--color-accent);
}

.guide-page .source-feedback h2 {
  border-bottom: none;
  padding-bottom: 8px;
}

.guide-page .source-feedback p {
  font-size: 14px;
  color: var(--color-text-secondary);
  line-height: 1.8;
  margin: 0;
}

/* ============================================================
   PAGES - 时间线页
   ============================================================ */

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

.main-content-column {
  min-width: 0;
  min-width: 520px;
}

.sidebar-area {
  position: sticky;
  top: calc(var(--header-height) + 24px);
}

.timeline-module {
  margin-bottom: 48px;
}

.timeline-module h2,
.key-nodes-module h2 {
  font-size: 20px;
  font-weight: 600;
  margin-bottom: 8px;
}

.module-intro {
  font-size: 15px;
  color: var(--color-text-secondary);
  margin-bottom: 24px;
}

.timeline-list {
  position: relative;
  padding-left: 32px;
}

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

.timeline-list .timeline-item {
  position: relative;
  background-color: var(--color-card);
  border-radius: var(--radius-md);
  padding: 20px 24px;
  margin-bottom: 20px;
  box-shadow: var(--shadow-sm);
}

.timeline-marker {
  position: absolute;
  left: -32px;
  top: 24px;
  width: 18px;
  height: 18px;
  border-radius: 50%;
  background-color: var(--color-card);
  border: 3px solid var(--color-accent);
  z-index: 1;
}

.timeline-content h3 {
  font-size: 16px;
  font-weight: 600;
  margin-bottom: 8px;
}

.timeline-content p {
  font-size: 14px;
  color: var(--color-text-secondary);
  line-height: 1.7;
  margin: 0;
}

.status-tag {
  display: inline-block;
  font-size: 12px;
  padding: 3px 10px;
  border-radius: 20px;
  margin-bottom: 8px;
  font-weight: 500;
}

.status-origin {
  background-color: #e8f4fd;
  color: #2980b9;
}

.status-develop {
  background-color: #fef9e7;
  color: #d4ac0d;
}

.status-climax {
  background-color: var(--color-accent-light);
  color: var(--color-accent);
}

.status-cooling {
  background-color: #eafaf1;
  color: #27ae60;
}

.status-ending {
  background-color: var(--color-bg);
  color: var(--color-text-secondary);
}

.key-nodes-module {
  margin-bottom: 48px;
}

.table-wrapper {
  overflow-x: auto;
  background-color: var(--color-card);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-sm);
}

.key-nodes-table {
  width: 100%;
  border-collapse: collapse;
  min-width: 480px;
}

.key-nodes-table thead {
  background-color: var(--color-primary);
}

.key-nodes-table th {
  color: #ffffff;
  font-size: 14px;
  font-weight: 600;
  text-align: left;
  padding: 14px 20px;
}

.key-nodes-table td {
  padding: 14px 20px;
  font-size: 14px;
  border-bottom: 1px solid var(--color-border);
  color: var(--color-text);
}

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

.key-nodes-table tbody tr:nth-child(even) {
  background-color: #f8f9fa;
}

.timeline-figure {
  margin: 32px 0;
  border-radius: var(--radius-md);
  overflow: hidden;
  box-shadow: var(--shadow-sm);
}

.timeline-figure img {
  width: 100%;
  height: 260px;
  object-fit: cover;
}

.timeline-figure figcaption {
  background-color: var(--color-card);
  padding: 12px 16px;
  font-size: 13px;
  color: var(--color-text-secondary);
  text-align: center;
}

.in-content-links {
  background-color: var(--color-card);
  border-radius: var(--radius-md);
  padding: 20px 24px;
  box-shadow: var(--shadow-sm);
}

.in-content-links p {
  font-size: 14px;
  color: var(--color-text-secondary);
  margin: 0;
  line-height: 1.8;
}

.in-content-links a {
  color: var(--color-accent);
  font-weight: 500;
  margin-right: 16px;
  display: inline-block;
}

.sidebar-links li {
  padding-left: 12px;
  position: relative;
}

.sidebar-links li::before {
  content: "›";
  position: absolute;
  left: 0;
  color: var(--color-accent);
  font-weight: 700;
}

/* ============================================================
   PAGES - 404 页
   ============================================================ */

.error-main {
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 80px 24px;
  min-height: calc(100vh - var(--header-height) - 300px);
}

.error-section {
  text-align: center;
  max-width: 560px;
  width: 100%;
}

.error-section h1 {
  font-size: 36px;
  font-weight: 700;
  color: var(--color-text);
  margin-bottom: 16px;
}

.error-code {
  font-size: 72px;
  font-weight: 700;
  color: var(--color-accent);
  line-height: 1.2;
  margin-bottom: 16px;
}

.error-message {
  font-size: 18px;
  color: var(--color-text-secondary);
  margin-bottom: 32px;
}

.error-home-link {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 44px;
  padding: 10px 32px;
  background-color: var(--color-accent);
  color: #ffffff;
  font-size: 15px;
  font-weight: 600;
  border-radius: var(--radius-sm);
  margin-bottom: 24px;
}

.error-home-link:hover {
  background-color: var(--color-accent-dark);
  color: #ffffff;
}

.error-suggestion {
  font-size: 14px;
  color: var(--color-text-secondary);
}

/* ============================================================
   RESPONSIVE - 响应式
   ============================================================ */

/* 平板及以下 */
@media (max-width: 1024px) {
  .hero-wrapper {
    gap: 32px;
  }

  .page-layout,
  .sidebar-left .page-layout {
    grid-template-columns: minmax(0, 1fr) 280px;
    gap: 24px;
  }

  .page-layout .main-content,
  .sidebar-left .page-layout .content-area,
  .main-content-column {
    min-width: 0;
  }

  .layout-shell {
    grid-template-columns: minmax(0, 1fr) 260px;
    gap: 24px;
  }
}

/* 手机端断点 768px */
@media (max-width: 768px) {
  :root {
    --header-height: 56px;
  }

  .header-container {
    padding: 0 16px;
    height: var(--header-height);
  }

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

  .brand-tagline {
    font-size: 11px;
  }

  /* 汉堡按钮显示 */
  .nav-toggle {
    display: flex;
  }

  /* 导航列表默认收起 */
  .site-nav {
    position: absolute;
    top: var(--header-height);
    left: 0;
    right: 0;
    background-color: var(--color-primary);
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.2);
    max-height: 0;
    overflow: hidden;
    transition: max-height var(--transition-normal);
  }

  .site-nav .nav-list.is-open {
    max-height: none;
  }

  .site-nav .nav-list {
    display: none;
    flex-direction: column;
    padding: 12px 16px;
    gap: 2px;
  }

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

  .nav-list a {
    padding: 14px 16px;
    font-size: 15px;
    border-radius: var(--radius-sm);
  }

  /* 首页 */
  .home-main {
    padding: 0 16px 40px;
  }

  .hero-section {
    padding: 32px 0 32px;
  }

  .hero-wrapper {
    grid-template-columns: 1fr;
    gap: 24px;
  }

  .hero-copy h1 {
    font-size: 26px;
  }

  .hero-figure img {
    height: 220px;
  }

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

  .hero-actions .btn-primary,
  .hero-actions .btn-secondary {
    width: 100%;
  }

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

  .timeline-preview .timeline-item {
    grid-template-columns: 1fr auto;
    gap: 8px 12px;
  }

  .timeline-event {
    grid-column: 1;
  }

  .timeline-status {
    grid-column: 2;
    grid-row: 1;
  }

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

  .pick-item {
    grid-template-columns: 1fr;
    gap: 12px;
  }

  /* 内页 */
  .inner-main {
    padding: 24px 16px 40px;
  }

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

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

  .page-layout,
  .sidebar-left .page-layout,
  .layout-shell {
    grid-template-columns: 1fr;
    gap: 24px;
  }

  .page-layout .sidebar,
  .page-layout .topic-sidebar,
  .page-layout .sidebar-area,
  .sidebar-left .page-layout .sidebar,
  .sidebar-area {
    position: static;
    order: 3;
    grid-column: 1;
    grid-row: auto;
  }

  .page-layout .main-content,
  .sidebar-left .page-layout .content-area,
  .main-content-column {
    grid-column: 1;
    grid-row: auto;
    order: 1;
  }

  /* 频道页 */
  .channel-list {
    grid-template-columns: 1fr;
  }

  .channel-item {
    padding: 16px;
  }

  /* 专题页 */
  .topic-grid {
    grid-template-columns: 1fr;
  }

  .highlight-item {
    grid-template-columns: 40px 1fr;
    padding: 16px;
  }

  /* 指南页 */
  .content-media-inline {
    float: none;
    width: 100%;
    margin: 16px 0;
  }

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

  .comparison-box {
    grid-template-columns: 1fr;
  }

  .steps-list li {
    padding: 16px 16px 16px 56px;
  }

  .steps-list li::before {
    left: 16px;
    top: 16px;
  }

  /* 时间线页 */
  .timeline-list {
    padding-left: 24px;
  }

  .timeline-list::before {
    left: 6px;
  }

  .timeline-marker {
    left: -24px;
    width: 14px;
    height: 14px;
  }

  .timeline-list .timeline-item {
    padding: 16px;
  }

  /* 页脚 */
  .footer-container {
    padding: 32px 16px 20px;
  }

  .footer-links {
    grid-template-columns: repeat(2, 1fr);
    gap: 24px;
  }

  .footer-brand p {
    margin-bottom: 24px;
  }

  /* 404 */
  .error-main {
    padding: 48px 16px;
  }

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

/* 小屏手机 */
@media (max-width: 480px) {
  .footer-links {
    grid-template-columns: 1fr 1fr;
    gap: 20px;
  }

  .footer-col h4 {
    font-size: 14px;
  }

  .footer-col a {
    font-size: 13px;
  }

  .topic-cards .topic-card img {
    height: 160px;
  }

  .topic-media img {
    height: 150px;
  }

  .timeline-figure img {
    height: 180px;
  }

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

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

/* ============================================================
   动效增强（不影响初始可见性）
   ============================================================ */

@media (prefers-reduced-motion: no-preference) {
  .news-item,
  .topic-card,
  .guide-card,
  .highlight-item,
  .pick-item,
  .timeline-list .timeline-item,
  .channel-item {
    animation: fade-in var(--transition-normal) both;
    animation-delay: calc(var(--item-index, 0) * 60ms);
  }

  @keyframes fade-in {
    from {
      opacity: 0;
      transform: translateY(8px);
    }
    to {
      opacity: 1;
      transform: translateY(0);
    }
  }
}

/* 主题明暗切换 - 尊重系统偏好 */
@media (prefers-color-scheme: dark) {
  :root {
    --color-bg: #1a1e24;
    --color-card: #242a33;
    --color-text: #e8eef2;
    --color-text-secondary: #a0aab4;
    --color-border: #37414d;
    --color-primary-light: #3d566e;
    --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.3);
    --shadow-md: 0 2px 8px rgba(0, 0, 0, 0.35);
  }

  .site-header,
  .site-footer {
    background-color: #161a1f;
  }

  .channel-item,
  .timeline-table tbody tr:nth-child(even),
  .key-nodes-table tbody tr:nth-child(even) {
    background-color: #1f252d;
  }

  .channel-item:hover {
    background-color: #2a323c;
  }

  .hero-figure img,
  .topic-media img,
  .timeline-figure img,
  .content-media img {
    filter: brightness(0.85);
  }
}