/* ==========================================================================
   51吃瓜莫里秀 · 全站样式表
   校园刊物风：活跃栏目色、社团影像、公告网格和青春编辑感
   ========================================================================== */

/* --------------------------------------------------------------------------
   Base — 基础变量、重置与全局字体
   -------------------------------------------------------------------------- */
:root {
  --color-coral: #FF6B6B;
  --color-teal: #4ECDC4;
  --color-sun: #FFE66D;
  --color-deep: #1A535C;
  --color-mint: #F7FFF7;

  --color-text: #2d3436;
  --color-text-light: #636e72;
  --color-text-muted: #95a5a6;
  --color-border: #e8ece9;
  --color-bg-soft: #f4f9f4;
  --color-white: #ffffff;

  --font-sans: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", Arial, sans-serif;
  --font-serif: Georgia, "Times New Roman", serif;

  --container-width: 1200px;
  --container-padding: 24px;
  --radius-sm: 4px;
  --radius-md: 6px;
  --radius-lg: 8px;
  --shadow-card: 0 2px 8px rgba(26, 83, 92, 0.08);
  --shadow-hover: 0 6px 20px rgba(26, 83, 92, 0.12);

  --header-height: 68px;
  --transition: 0.25s ease;
}

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

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

body {
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.7;
  color: var(--color-text);
  background-color: var(--color-mint);
  -webkit-font-smoothing: antialiased;
}

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

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

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

ul,
ol {
  list-style: none;
}

h1,
h2,
h3,
h4,
h5,
h6 {
  font-weight: 700;
  line-height: 1.3;
  color: var(--color-deep);
}

/* --------------------------------------------------------------------------
   Layout — 全站骨架、页头、页脚、容器
   -------------------------------------------------------------------------- */

/* 站点骨架：body 作为 flex 纵向布局，footer 沉底 */
.site-body {
  display: flex;
  flex-direction: column;
  min-height: 100vh;
}

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

/* 统一内容容器 */
.header-shell,
.footer-shell,
.hero-focus,
.channel-belt,
.latest-news,
.topic-recommend,
.editor-picks,
.page-header-shell,
.channel-list-shell,
.channel-notes-shell,
.topic-list,
.participation,
.discussion,
.guide-section,
.page-layout,
.faq-section {
  max-width: var(--container-width);
  margin-left: auto;
  margin-right: auto;
  padding-left: var(--container-padding);
  padding-right: var(--container-padding);
}

/* --------------------------------------------------------------------------
   页头 — 品牌 + 主导航
   -------------------------------------------------------------------------- */
.site-header {
  background-color: var(--color-white);
  border-bottom: 3px solid var(--color-sun);
  position: sticky;
  top: 0;
  z-index: 100;
}

.header-shell {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: var(--header-height);
  gap: 24px;
}

.brand {
  display: flex;
  flex-direction: column;
  line-height: 1.2;
  flex-shrink: 0;
}

.brand-name {
  font-size: 22px;
  font-weight: 800;
  color: var(--color-deep);
  letter-spacing: 0;
}

.brand-name::first-letter {
  color: var(--color-coral);
}

.brand-slogan {
  font-size: 12px;
  color: var(--color-text-muted);
  letter-spacing: 1px;
}

/* 主导航 */
.site-nav {
  display: block;
}

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

.nav-list li a {
  display: block;
  padding: 8px 16px;
  font-size: 15px;
  font-weight: 500;
  color: var(--color-text);
  border-radius: var(--radius-md);
  transition: background-color var(--transition), color var(--transition);
}

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

.nav-list li a.is-current {
  color: var(--color-white);
  background-color: var(--color-deep);
  font-weight: 600;
}

/* 移动端汉堡按钮 */
.nav-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 44px;
  height: 44px;
  padding: 10px;
  background: none;
  border: none;
  cursor: pointer;
}

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

/* --------------------------------------------------------------------------
   页脚 — 四栏分组链接
   -------------------------------------------------------------------------- */
.site-footer {
  background-color: var(--color-deep);
  color: rgba(255, 255, 255, 0.85);
  margin-top: 64px;
}

.footer-shell {
  padding-top: 48px;
  padding-bottom: 24px;
}

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

.footer-brand__name {
  font-size: 20px;
  font-weight: 700;
  color: var(--color-white);
  margin-bottom: 6px;
}

.footer-brand__desc {
  font-size: 14px;
  color: rgba(255, 255, 255, 0.7);
  max-width: 480px;
}

.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 {
  font-size: 14px;
  font-weight: 600;
  color: var(--color-sun);
  margin-bottom: 12px;
}

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

.footer-col ul li a {
  font-size: 14px;
  color: rgba(255, 255, 255, 0.75);
  transition: color var(--transition);
}

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

.footer-bottom {
  padding-top: 20px;
  text-align: center;
  font-size: 13px;
  color: rgba(255, 255, 255, 0.5);
}

/* --------------------------------------------------------------------------
   Components — 面包屑、页标题、通用卡片、按钮、列表
   -------------------------------------------------------------------------- */

/* 面包屑 */
.breadcrumb {
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 20px var(--container-padding) 0;
  font-size: 14px;
  color: var(--color-text-muted);
}

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

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

.breadcrumb-sep {
  margin: 0 8px;
  color: var(--color-border);
}

.breadcrumb-current {
  color: var(--color-deep);
  font-weight: 600;
}

/* 页面标题区（内页统一） */
.page-header {
  background-color: var(--color-white);
  border-bottom: 1px solid var(--color-border);
  margin-bottom: 40px;
}

.page-header-shell {
  padding-top: 32px;
  padding-bottom: 32px;
}

.page-title {
  font-size: 32px;
  font-weight: 800;
  color: var(--color-deep);
  margin-bottom: 8px;
}

.page-lead,
.page-description {
  font-size: 16px;
  color: var(--color-text-light);
  max-width: 720px;
  line-height: 1.7;
}

/* 通用 section 标题 */
.section-title {
  font-size: 24px;
  font-weight: 700;
  color: var(--color-deep);
  margin-bottom: 8px;
  position: relative;
  padding-bottom: 10px;
}

.section-title::after {
  content: "";
  display: block;
  width: 40px;
  height: 3px;
  background-color: var(--color-coral);
  border-radius: 2px;
  margin-top: 8px;
}

/* 通用描述文字 */
.section-desc,
.section-lead {
  font-size: 15px;
  color: var(--color-text-light);
  margin-bottom: 24px;
  line-height: 1.7;
}

/* 通用卡片 */
.topic-card,
.channel-card {
  background-color: var(--color-white);
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-card);
  transition: box-shadow var(--transition), transform var(--transition);
}

.topic-card:hover,
.channel-card:hover {
  box-shadow: var(--shadow-hover);
  transform: translateY(-2px);
}

.topic-card img,
.channel-card img,
.hero-focus img,
.article-media img,
.content-media img {
  width: 100%;
  object-fit: cover;
}

/* 图片容器稳定约束 */
.hero-focus__media img {
  aspect-ratio: 16 / 10;
}

.topic-card__media img,
.topic-card > img {
  aspect-ratio: 16 / 9;
}

.channel-card-media img {
  aspect-ratio: 16 / 9;
}

.article-media img {
  aspect-ratio: 16 / 9;
}

.content-media img {
  aspect-ratio: 16 / 9;
}

figcaption {
  font-size: 13px;
  color: var(--color-text-muted);
  padding: 8px 4px 0;
  line-height: 1.5;
}

/* 通用按钮样式 */
.hero-focus__link,
.topic-card__link,
.channel-link,
.error-btn {
  display: inline-block;
  padding: 8px 20px;
  font-size: 14px;
  font-weight: 600;
  color: var(--color-white);
  background-color: var(--color-coral);
  border-radius: var(--radius-md);
  transition: background-color var(--transition);
}

.hero-focus__link:hover,
.topic-card__link:hover,
.channel-link:hover,
.error-btn:hover {
  background-color: var(--color-deep);
  color: var(--color-white);
}

/* 内页通用 main */
.inner-main {
  padding-bottom: 48px;
}

/* --------------------------------------------------------------------------
   Pages — 首页
   -------------------------------------------------------------------------- */

/* 首页 hero 焦点报道：全宽列表首屏 */
.hero-focus {
  display: grid;
  grid-template-columns: 1.2fr 1fr;
  gap: 40px;
  align-items: center;
  padding-top: 48px;
  padding-bottom: 48px;
}

.hero-focus__content {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: 16px;
}

.hero-focus__tag {
  display: inline-block;
  padding: 4px 14px;
  font-size: 13px;
  font-weight: 600;
  color: var(--color-deep);
  background-color: var(--color-sun);
  border-radius: var(--radius-sm);
  letter-spacing: 0;
}

.hero-focus__heading {
  font-size: 34px;
  font-weight: 800;
  line-height: 1.25;
  color: var(--color-deep);
}

.hero-focus__excerpt {
  font-size: 16px;
  color: var(--color-text-light);
  line-height: 1.8;
  max-width: 520px;
}

.hero-focus__link {
  margin-top: 8px;
}

.hero-focus__media {
  margin: 0;
}

.hero-focus__media img {
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-card);
}

.hero-focus__media figcaption {
  text-align: center;
}

/* 频道导航带：横向标签 */
.channel-belt {
  padding-top: 32px;
  padding-bottom: 32px;
}

.channel-belt .section-title {
  font-size: 20px;
}

.channel-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 16px;
}

.channel-tag {
  display: inline-block;
  padding: 8px 22px;
  font-size: 14px;
  font-weight: 600;
  color: var(--color-deep);
  background-color: var(--color-white);
  border: 2px solid var(--color-teal);
  border-radius: 999px;
  transition: background-color var(--transition), color var(--transition);
}

.channel-tag:hover {
  background-color: var(--color-teal);
  color: var(--color-white);
}

/* 最新资讯列表 */
.latest-news {
  padding-top: 24px;
  padding-bottom: 24px;
}

.news-list {
  display: flex;
  flex-direction: column;
  gap: 16px;
  margin-top: 16px;
}

.news-item {
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 12px 24px;
  align-items: baseline;
  padding: 16px 20px;
  background-color: var(--color-white);
  border-left: 4px solid var(--color-teal);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-card);
  transition: border-color var(--transition);
}

.news-item:hover {
  border-left-color: var(--color-coral);
}

.news-item h3 {
  font-size: 17px;
  font-weight: 600;
  line-height: 1.4;
}

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

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

.news-item__excerpt {
  grid-column: 1 / -1;
  font-size: 14px;
  color: var(--color-text-light);
  line-height: 1.6;
}

.news-item time {
  font-size: 13px;
  color: var(--color-text-muted);
  white-space: nowrap;
}

/* 专题推荐区：两张卡片 */
.topic-recommend {
  padding-top: 32px;
  padding-bottom: 32px;
}

.topic-cards {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 24px;
  margin-top: 16px;
}

.topic-card {
  display: flex;
  flex-direction: column;
}

.topic-card img {
  aspect-ratio: 16 / 9;
}

.topic-card__body {
  padding: 20px;
  display: flex;
  flex-direction: column;
  gap: 8px;
  flex: 1;
}

.topic-card__body h3 {
  font-size: 18px;
  font-weight: 700;
}

.topic-card__body h3 a {
  color: var(--color-deep);
}

.topic-card__body h3 a:hover {
  color: var(--color-coral);
}

.topic-card__body p {
  font-size: 14px;
  color: var(--color-text-light);
  line-height: 1.6;
  flex: 1;
}

/* 编辑推荐：三条横向条目 */
.editor-picks {
  padding-top: 32px;
  padding-bottom: 48px;
}

.editors-list {
  display: flex;
  flex-direction: column;
  gap: 12px;
  margin-top: 16px;
}

.editor-item {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 16px;
  align-items: center;
  padding: 16px 20px;
  background-color: var(--color-white);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-card);
}

.editor-item__badge {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  font-size: 14px;
  font-weight: 700;
  color: var(--color-deep);
  background-color: var(--color-sun);
  border-radius: var(--radius-sm);
  flex-shrink: 0;
}

.editor-item h3 {
  font-size: 16px;
  font-weight: 600;
  line-height: 1.4;
}

.editor-item h3 a {
  color: var(--color-deep);
}

.editor-item h3 a:hover {
  color: var(--color-coral);
}

.editor-item p {
  grid-column: 2;
  font-size: 14px;
  color: var(--color-text-light);
  line-height: 1.5;
}

/* --------------------------------------------------------------------------
   Pages — 频道分类（channels.html）
   -------------------------------------------------------------------------- */

.channel-list-section {
  padding-bottom: 48px;
}

.channel-list-title,
.channel-notes-title {
  font-size: 22px;
  font-weight: 700;
  color: var(--color-deep);
  margin-bottom: 8px;
}

.channel-list-intro,
.channel-notes-intro {
  font-size: 15px;
  color: var(--color-text-light);
  margin-bottom: 24px;
}

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

.channel-card {
  display: flex;
  flex-direction: column;
}

.channel-card-body {
  padding: 20px;
  display: flex;
  flex-direction: column;
  gap: 8px;
  flex: 1;
}

.channel-card-body h3 {
  font-size: 18px;
  font-weight: 700;
}

.channel-card-body p {
  font-size: 14px;
  color: var(--color-text-light);
  line-height: 1.6;
  flex: 1;
}

.channel-link {
  align-self: flex-start;
  margin-top: 8px;
}

/* 频道说明区 */
.channel-notes-section {
  background-color: var(--color-white);
  border-top: 1px solid var(--color-border);
  border-bottom: 1px solid var(--color-border);
  padding-top: 40px;
  padding-bottom: 40px;
}

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

.notes-item {
  padding: 20px;
  background-color: var(--color-bg-soft);
  border-radius: var(--radius-md);
  border-left: 3px solid var(--color-teal);
}

.notes-item h3 {
  font-size: 15px;
  font-weight: 600;
  margin-bottom: 6px;
}

.notes-item p {
  font-size: 14px;
  color: var(--color-text-light);
  line-height: 1.6;
}

.channel-related {
  margin-top: 24px;
  font-size: 14px;
  color: var(--color-text-light);
}

.channel-related a {
  margin-right: 16px;
  font-weight: 500;
}

/* --------------------------------------------------------------------------
   Pages — 内容专题（topics.html）
   -------------------------------------------------------------------------- */

.topic-list {
  padding-bottom: 48px;
}

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

.topic-card__summary {
  font-size: 14px;
  color: var(--color-text-light);
  line-height: 1.6;
  flex: 1;
}

.topic-card__link {
  align-self: flex-start;
  margin-top: 8px;
}

/* 参与流程 */
.participation {
  padding-top: 40px;
  padding-bottom: 40px;
  background-color: var(--color-white);
  border-top: 1px solid var(--color-border);
  border-bottom: 1px solid var(--color-border);
}

.participation-steps {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
  counter-reset: step-counter;
}

.participation-step {
  position: relative;
  padding: 24px 20px 20px;
  background-color: var(--color-bg-soft);
  border-radius: var(--radius-md);
  border-top: 3px solid var(--color-teal);
}

.participation-step::before {
  counter-increment: step-counter;
  content: counter(step-counter);
  display: flex;
  align-items: center;
  justify-content: center;
  width: 32px;
  height: 32px;
  font-size: 15px;
  font-weight: 700;
  color: var(--color-white);
  background-color: var(--color-deep);
  border-radius: 50%;
  margin-bottom: 12px;
}

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

.participation-step p {
  font-size: 14px;
  color: var(--color-text-light);
  line-height: 1.6;
}

/* 讨论入口 */
.discussion {
  padding-top: 40px;
  padding-bottom: 40px;
}

.discussion-links {
  display: flex;
  flex-wrap: wrap;
  gap: 16px;
}

.discussion-link {
  display: inline-block;
  padding: 10px 24px;
  font-size: 14px;
  font-weight: 600;
  color: var(--color-deep);
  background-color: var(--color-white);
  border: 2px solid var(--color-coral);
  border-radius: var(--radius-md);
  transition: background-color var(--transition), color var(--transition);
}

.discussion-link:hover {
  background-color: var(--color-coral);
  color: var(--color-white);
}

/* 相关链接 */
.related-links {
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 24px var(--container-padding);
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px 20px;
  border-top: 1px solid var(--color-border);
}

.related-links-label {
  font-size: 14px;
  font-weight: 600;
  color: var(--color-deep);
}

.related-links-item {
  font-size: 14px;
  color: var(--color-text-light);
}

.related-links-item:hover {
  color: var(--color-coral);
}

/* --------------------------------------------------------------------------
   Pages — 实用指南（guide.html）
   -------------------------------------------------------------------------- */

.guide-section {
  padding-top: 8px;
  padding-bottom: 40px;
}

.guide-section h2 {
  font-size: 22px;
  font-weight: 700;
  color: var(--color-deep);
  margin-bottom: 8px;
}

.steps-list {
  display: flex;
  flex-direction: column;
  gap: 16px;
  margin-top: 16px;
}

.step-item {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 16px;
  padding: 20px;
  background-color: var(--color-white);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-card);
  counter-increment: step-count;
}

.step-item::before {
  content: counter(step-count, decimal-leading-zero);
  font-size: 20px;
  font-weight: 800;
  color: var(--color-coral);
  line-height: 1;
  padding-top: 4px;
}

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

.step-content p {
  font-size: 14px;
  color: var(--color-text-light);
  line-height: 1.6;
}

.step-content p a {
  color: var(--color-deep);
  font-weight: 500;
}

.step-content p a:hover {
  color: var(--color-coral);
}

.step-expect {
  margin-top: 8px;
  padding: 8px 12px;
  background-color: var(--color-bg-soft);
  border-radius: var(--radius-sm);
  border-left: 3px solid var(--color-teal);
  font-size: 13px;
  color: var(--color-text-light);
}

.step-exception {
  margin-top: 6px;
  font-size: 13px;
  color: var(--color-text-muted);
}

/* 资源卡片（guide 页内部模块） */
.resource-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 16px;
  margin-top: 16px;
}

.resource-card {
  padding: 16px 20px;
  background-color: var(--color-white);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-card);
}

.resource-card h3 {
  font-size: 15px;
  font-weight: 600;
  margin-bottom: 4px;
}

.resource-card p {
  font-size: 14px;
  color: var(--color-text-light);
}

/* FAQ 手风琴（guide 页内嵌） */
.faq-list {
  display: flex;
  flex-direction: column;
  gap: 12px;
  margin-top: 16px;
}

.faq-item {
  background-color: var(--color-white);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-card);
  overflow: hidden;
}

.faq-item summary {
  padding: 16px 20px;
  font-size: 15px;
  font-weight: 600;
  color: var(--color-deep);
  cursor: pointer;
  list-style: none;
  position: relative;
  padding-right: 44px;
  transition: background-color var(--transition);
}

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

.faq-item summary::after {
  content: "+";
  position: absolute;
  right: 18px;
  top: 50%;
  transform: translateY(-50%);
  font-size: 20px;
  font-weight: 400;
  color: var(--color-teal);
  transition: transform var(--transition);
}

.faq-item[open] summary::after {
  transform: translateY(-50%) rotate(45deg);
}

.faq-item[open] summary {
  background-color: var(--color-bg-soft);
}

.faq-answer {
  padding: 0 20px 16px;
  font-size: 14px;
  color: var(--color-text-light);
  line-height: 1.7;
}

.faq-answer p {
  margin-bottom: 8px;
}

.faq-answer p:last-child {
  margin-bottom: 0;
}

.faq-answer a {
  color: var(--color-deep);
  font-weight: 500;
}

.faq-answer a:hover {
  color: var(--color-coral);
}

/* --------------------------------------------------------------------------
   Pages — 深度解读（insight.html）
   -------------------------------------------------------------------------- */

/* 侧栏在左的布局：main 与 aside 为 body 直接子元素时，body 作为 grid 容器 */
.site-body.page-insight {
  display: flex;
  flex-direction: column;
}

.page-layout {
  display: grid;
  grid-template-columns: 280px 1fr;
  gap: 40px;
  align-items: start;
  padding-top: 8px;
  padding-bottom: 48px;
}

/* 侧栏在前：sidebar-left 位于 page-layout 自身 */
.sidebar-left {
  grid-template-columns: 280px 1fr;
}

.sidebar-left .toc-sidebar {
  grid-column: 1;
  grid-row: 1;
}

.sidebar-left .insight-article {
  grid-column: 2;
  grid-row: 1;
}

/* 目录卡片 */
.toc-card {
  background-color: var(--color-white);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-card);
  padding: 20px;
  border-left: 4px solid var(--color-teal);
  position: sticky;
  top: calc(var(--header-height) + 20px);
}

.toc-title {
  font-size: 16px;
  font-weight: 700;
  color: var(--color-deep);
  margin-bottom: 12px;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--color-border);
}

.toc-list {
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.toc-list li a {
  display: block;
  padding: 6px 10px;
  font-size: 14px;
  color: var(--color-text-light);
  border-radius: var(--radius-sm);
  transition: background-color var(--transition), color var(--transition);
}

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

/* 文章正文 */
.insight-article {
  min-width: 0;
}

.content-section {
  margin-bottom: 40px;
}

.content-section h2 {
  font-size: 24px;
  font-weight: 700;
  color: var(--color-deep);
  margin-bottom: 16px;
  padding-bottom: 8px;
  border-bottom: 2px solid var(--color-sun);
}

.content-section h3 {
  font-size: 18px;
  font-weight: 600;
  color: var(--color-deep);
  margin-top: 24px;
  margin-bottom: 10px;
}

.content-section p {
  font-size: 15px;
  line-height: 1.8;
  color: var(--color-text);
  margin-bottom: 16px;
}

.article-media {
  margin: 20px 0;
}

.article-media img {
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-card);
}

.article-media figcaption {
  text-align: center;
  padding-top: 10px;
}

/* 相关链接（insight 页） */
.insight-article .related-links {
  padding: 24px 0;
  border-top: 1px solid var(--color-border);
  border-bottom: 1px solid var(--color-border);
  margin-top: 24px;
}

.insight-article .related-links h3 {
  font-size: 16px;
  font-weight: 700;
  margin-bottom: 12px;
}

.insight-article .related-links ul {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 20px;
}

.insight-article .related-links ul li a {
  font-size: 14px;
  color: var(--color-text-light);
}

.insight-article .related-links ul li a:hover {
  color: var(--color-coral);
}

/* --------------------------------------------------------------------------
   Pages — 常见问题（faq.html）
   -------------------------------------------------------------------------- */

.faq-section {
  padding-top: 8px;
  padding-bottom: 40px;
}

.faq-section .section-title {
  font-size: 20px;
  margin-bottom: 16px;
}

.content-media-inline {
  max-width: 640px;
  margin: 16px 0 24px;
}

.content-media-inline img {
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-card);
}

/* 反馈面板 */
.feedback-panel {
  background-color: var(--color-white);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-card);
  padding: 24px;
  border-left: 4px solid var(--color-coral);
}

.feedback-panel p {
  font-size: 15px;
  color: var(--color-text);
  margin-bottom: 16px;
  line-height: 1.7;
}

.feedback-list {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.feedback-list li a {
  display: inline-block;
  padding: 8px 18px;
  font-size: 14px;
  font-weight: 500;
  color: var(--color-deep);
  background-color: var(--color-bg-soft);
  border-radius: var(--radius-md);
  transition: background-color var(--transition), color var(--transition);
}

.feedback-list li a:hover {
  background-color: var(--color-deep);
  color: var(--color-white);
}

/* --------------------------------------------------------------------------
   Pages — 404
   -------------------------------------------------------------------------- */

.error-main {
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 80px 24px;
}

.error-content {
  text-align: center;
  max-width: 560px;
}

.error-code {
  font-size: 72px;
  font-weight: 800;
  color: var(--color-coral);
  line-height: 1;
  margin-bottom: 16px;
}

.error-content h1 {
  font-size: 24px;
  font-weight: 700;
  color: var(--color-deep);
  margin-bottom: 12px;
}

.error-desc {
  font-size: 15px;
  color: var(--color-text-light);
  margin-bottom: 24px;
  line-height: 1.7;
}

.error-actions {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 12px;
  margin-bottom: 24px;
}

.error-btn {
  padding: 10px 28px;
}

.error-link {
  display: inline-block;
  padding: 10px 20px;
  font-size: 14px;
  font-weight: 500;
  color: var(--color-deep);
  border: 2px solid var(--color-teal);
  border-radius: var(--radius-md);
  transition: background-color var(--transition), color var(--transition);
}

.error-link:hover {
  background-color: var(--color-teal);
  color: var(--color-white);
}

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

.error-help a {
  color: var(--color-deep);
  font-weight: 500;
}

.error-help a:hover {
  color: var(--color-coral);
}

/* --------------------------------------------------------------------------
   Responsive — 响应式断点（768px）
   -------------------------------------------------------------------------- */
@media (max-width: 768px) {
  :root {
    --container-padding: 16px;
    --header-height: 60px;
  }

  /* 页头：汉堡菜单 */
  .nav-toggle {
    display: flex;
  }

  .site-nav {
    position: absolute;
    top: var(--header-height);
    left: 0;
    right: 0;
    background-color: var(--color-white);
    border-bottom: 3px solid var(--color-sun);
    box-shadow: 0 8px 16px rgba(0, 0, 0, 0.08);
  }

  .nav-list {
    display: none;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    padding: 8px 16px 16px;
  }

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

  .nav-list li a {
    padding: 12px 16px;
    font-size: 16px;
    border-radius: var(--radius-md);
  }

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

  /* 首页 hero */
  .hero-focus {
    grid-template-columns: 1fr;
    gap: 24px;
    padding-top: 32px;
    padding-bottom: 32px;
  }

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

  /* 首页专题卡片 */
  .topic-cards {
    grid-template-columns: 1fr;
  }

  /* 首页新闻条目 */
  .news-item {
    grid-template-columns: 1fr;
    gap: 8px;
  }

  .news-item time {
    grid-column: 1;
  }

  /* 编辑推荐 */
  .editor-item {
    grid-template-columns: 1fr;
    gap: 8px;
  }

  .editor-item p {
    grid-column: 1;
  }

  /* 频道分类 */
  .channel-grid {
    grid-template-columns: 1fr;
  }

  .notes-panel {
    grid-template-columns: 1fr;
  }

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

  .participation-steps {
    grid-template-columns: 1fr;
    gap: 16px;
  }

  /* 指南页 */
  .resource-grid {
    grid-template-columns: 1fr;
  }

  /* 深度解读：侧栏折叠到正文之前 */
  .page-layout,
  .sidebar-left {
    grid-template-columns: 1fr;
    gap: 24px;
  }

  .sidebar-left .toc-sidebar,
  .sidebar-left .insight-article {
    grid-column: 1;
    grid-row: auto;
  }

  .toc-card {
    position: static;
  }

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

  /* 面包屑 */
  .breadcrumb {
    padding-top: 16px;
  }

  /* 页标题区 */
  .page-header-shell {
    padding-top: 24px;
    padding-bottom: 24px;
  }

  /* 404 */
  .error-code {
    font-size: 56px;
  }
}

/* 极小屏兜底：390px 以下 */
@media (max-width: 390px) {
  .brand-name {
    font-size: 18px;
  }

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

  .footer-links {
    grid-template-columns: 1fr;
    gap: 20px;
  }

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

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