/* ==========================================================
   91吃瓜 · 整站样式表
   瑞士网格风：严格对齐、无衬线字体、信息编号、留白准确
   ========================================================== */

/* ----------------------------------------------------------
   Base — 基础变量、重置、字体、通用元素
   ---------------------------------------------------------- */
:root {
  --color-ink: #1a1a1a;
  --color-bg: #f5f5f5;
  --color-accent: #c0392b;
  --color-navy: #2c3e50;
  --color-white: #ffffff;
  --color-gray-light: #e8e8e8;
  --color-gray-mid: #9a9a9a;
  --color-gray-text: #5c5c5c;
  --color-line: #dcdcdc;

  --font-sans: "Helvetica Neue", Helvetica, Arial, "PingFang SC", "Microsoft YaHei", sans-serif;

  --container-width: 1200px;
  --container-pad: 24px;
  --radius-sm: 4px;
  --radius-md: 8px;

  --header-h: 68px;
  --section-gap: 56px;
  --card-gap: 24px;
}

*,
*::before,
*::after {
  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: 1.6;
  color: var(--color-ink);
  background-color: var(--color-bg);
  -webkit-font-smoothing: antialiased;
}

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

a {
  color: var(--color-navy);
  text-decoration: none;
  transition: color 0.2s ease;
}

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

ul,
ol {
  list-style: none;
}

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

/* 页面级布局容器 */
.site-body {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

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

/* ----------------------------------------------------------
   Layout — 页头、导航、页脚、布局外壳
   ---------------------------------------------------------- */

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

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

.brand {
  display: flex;
  flex-direction: column;
  line-height: 1.15;
  flex-shrink: 0;
}

.brand-name {
  font-size: 26px;
  font-weight: 800;
  color: var(--color-ink);
  letter-spacing: 0.02em;
}

.brand-slogan {
  font-size: 12px;
  color: var(--color-gray-mid);
  letter-spacing: 0.08em;
}

/* ---------- 主导航 ---------- */
.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: 15px;
  font-weight: 600;
  color: var(--color-navy);
  border-radius: var(--radius-sm);
  transition: background-color 0.2s ease, color 0.2s ease;
}

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

.nav-list li a.is-current {
  color: var(--color-white);
  background-color: var(--color-accent);
}

/* 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: none;
  border: 1px solid var(--color-line);
  border-radius: var(--radius-sm);
  cursor: pointer;
  flex-shrink: 0;
}

.nav-toggle-bar {
  display: block;
  width: 100%;
  height: 2px;
  background-color: var(--color-ink);
  border-radius: 2px;
  transition: transform 0.2s ease, opacity 0.2s ease;
}

/* ---------- 页脚 ---------- */
.site-footer {
  background-color: var(--color-navy);
  color: #d5dbe0;
  margin-top: 0;
}

.footer-inner {
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 48px var(--container-pad) 32px;
  display: grid;
  grid-template-columns: 1.2fr 2fr;
  gap: 48px;
}

.footer-brand-name {
  font-size: 22px;
  font-weight: 700;
  color: var(--color-white);
  margin-bottom: 8px;
}

.footer-brand-desc {
  font-size: 14px;
  line-height: 1.7;
  color: #aeb8bf;
}

.footer-links {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.footer-col-title {
  font-size: 14px;
  font-weight: 700;
  color: var(--color-white);
  margin-bottom: 14px;
  letter-spacing: 0.04em;
}

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

.footer-col ul li a {
  font-size: 14px;
  color: #aeb8bf;
}

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

.footer-bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.12);
  padding: 18px var(--container-pad);
  text-align: center;
}

.footer-bottom p {
  max-width: var(--container-width);
  margin: 0 auto;
  font-size: 13px;
  color: #8a959c;
}

/* ---------- 面包屑 ---------- */
.breadcrumb {
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 18px var(--container-pad) 0;
  font-size: 13px;
  color: var(--color-gray-mid);
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 6px;
}

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

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

.breadcrumb-sep {
  color: var(--color-gray-mid);
  margin: 0 2px;
}

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

/* 面包屑（guide.html 的独立面包屑） */
.breadcrumb-inner {
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 0 var(--container-pad);
}

.breadcrumb-list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 6px;
  padding: 18px 0 0;
  font-size: 13px;
  color: var(--color-gray-mid);
}

.breadcrumb-list li a {
  color: var(--color-navy);
}

/* ---------- 内页布局外壳 ---------- */
.inner-main {
  width: 100%;
}

.layout-shell {
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 0 var(--container-pad);
  width: 100%;
}

/* 页面标题区（统一） */
.page-header {
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 32px var(--container-pad) 8px;
}

.page-header-inner {
  max-width: var(--container-width);
}

.page-title {
  font-size: 28px;
  font-weight: 700;
  color: var(--color-ink);
  margin-bottom: 8px;
}

.page-description,
.page-subtitle {
  font-size: 15px;
  color: var(--color-gray-text);
  max-width: 760px;
  line-height: 1.7;
}

/* 通用 section 标题 */
.section-title {
  font-size: 22px;
  font-weight: 700;
  color: var(--color-ink);
  margin-bottom: 16px;
  position: relative;
  padding-left: 14px;
}

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

.section-desc,
.section-lead {
  font-size: 15px;
  color: var(--color-gray-text);
  line-height: 1.7;
  margin-bottom: 24px;
  max-width: 760px;
}

/* ----------------------------------------------------------
   Components — 通用组件
   ---------------------------------------------------------- */

/* ---------- 焦点文章 ---------- */
.feature-story {
  background-color: var(--color-white);
  border-radius: var(--radius-md);
  overflow: hidden;
  border: 1px solid var(--color-line);
}

.feature-media {
  aspect-ratio: 16 / 9;
  overflow: hidden;
  background-color: var(--color-gray-light);
}

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

.feature-content {
  padding: 24px 28px 28px;
}

.story-tag {
  display: inline-block;
  font-size: 12px;
  font-weight: 700;
  color: var(--color-accent);
  background-color: rgba(192, 57, 43, 0.08);
  padding: 3px 10px;
  border-radius: var(--radius-sm);
  margin-bottom: 12px;
  letter-spacing: 0.04em;
}

.feature-title {
  font-size: 26px;
  line-height: 1.3;
  margin-bottom: 12px;
}

.feature-summary {
  font-size: 15px;
  color: var(--color-gray-text);
  line-height: 1.7;
  margin-bottom: 16px;
}

.feature-link {
  font-size: 14px;
  font-weight: 700;
  color: var(--color-accent);
  display: inline-flex;
  align-items: center;
  gap: 4px;
}

.feature-link:hover {
  text-decoration: underline;
}

/* ---------- 快讯窄栏 ---------- */
.flash-column {
  background-color: var(--color-white);
  border: 1px solid var(--color-line);
  border-top: 3px solid var(--color-accent);
  border-radius: var(--radius-md);
  padding: 20px 20px 12px;
}

.flash-title {
  font-size: 16px;
  font-weight: 700;
  color: var(--color-navy);
  padding-bottom: 10px;
  border-bottom: 1px solid var(--color-line);
  margin-bottom: 4px;
}

.flash-list li a {
  display: block;
  padding: 10px 0;
  font-size: 14px;
  line-height: 1.5;
  color: var(--color-ink);
  border-bottom: 1px dashed var(--color-line);
  transition: color 0.2s ease, padding-left 0.2s ease;
}

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

.flash-list li a:hover {
  color: var(--color-accent);
  padding-left: 6px;
}

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

.channel-tag {
  display: inline-flex;
  align-items: center;
  padding: 10px 22px;
  background-color: var(--color-white);
  border: 1px solid var(--color-line);
  border-radius: var(--radius-sm);
  font-size: 15px;
  font-weight: 600;
  color: var(--color-navy);
  transition: all 0.2s ease;
}

.channel-tag:hover {
  border-color: var(--color-accent);
  color: var(--color-accent);
  background-color: rgba(192, 57, 43, 0.04);
}

/* ---------- 资讯列表 ---------- */
.news-list {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0 var(--card-gap);
}

.news-item {
  border-bottom: 1px solid var(--color-line);
}

.news-link {
  display: block;
  padding: 18px 4px;
  transition: background-color 0.2s ease;
}

.news-link:hover {
  background-color: rgba(255, 255, 255, 0.6);
}

.news-headline {
  font-size: 16px;
  font-weight: 700;
  line-height: 1.4;
  margin-bottom: 6px;
  color: var(--color-ink);
}

.news-link:hover .news-headline {
  color: var(--color-accent);
}

.news-excerpt {
  font-size: 14px;
  color: var(--color-gray-text);
  line-height: 1.6;
  margin-bottom: 8px;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.news-date {
  font-size: 12px;
  color: var(--color-gray-mid);
}

/* ---------- 专题卡片 ---------- */
.topic-card {
  background-color: var(--color-white);
  border: 1px solid var(--color-line);
  border-radius: var(--radius-md);
  overflow: hidden;
  display: flex;
  flex-direction: column;
  transition: box-shadow 0.25s ease, transform 0.25s ease;
}

.topic-card:hover {
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.08);
  transform: translateY(-2px);
}

.topic-media {
  aspect-ratio: 16 / 9;
  background-color: var(--color-gray-light);
  overflow: hidden;
}

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

.topic-body {
  padding: 20px 22px 22px;
  display: flex;
  flex-direction: column;
  flex: 1;
}

.topic-title {
  font-size: 18px;
  font-weight: 700;
  margin-bottom: 8px;
  line-height: 1.4;
}

.topic-summary,
.topic-excerpt {
  font-size: 14px;
  color: var(--color-gray-text);
  line-height: 1.65;
  margin-bottom: 14px;
  flex: 1;
}

.topic-link {
  font-size: 14px;
  font-weight: 700;
  color: var(--color-accent);
  display: inline-flex;
  align-items: center;
  gap: 4px;
}

.topic-link:hover {
  text-decoration: underline;
}

/* ---------- 编辑推荐 ---------- */
.editorial-list {
  display: grid;
  grid-template-columns: 1fr 1fr 1fr;
  gap: var(--card-gap);
}

.editorial-item {
  background-color: var(--color-white);
  border: 1px solid var(--color-line);
  border-left: 4px solid var(--color-accent);
  border-radius: var(--radius-sm);
  padding: 20px 20px 18px;
  display: flex;
  gap: 16px;
  transition: box-shadow 0.2s ease;
}

.editorial-item:hover {
  box-shadow: 0 3px 12px rgba(0, 0, 0, 0.07);
}

.editorial-index {
  font-size: 28px;
  font-weight: 800;
  color: var(--color-accent);
  line-height: 1;
  flex-shrink: 0;
  font-style: italic;
}

.editorial-title {
  font-size: 16px;
  font-weight: 700;
  margin-bottom: 6px;
  line-height: 1.4;
}

.editorial-reason {
  font-size: 13px;
  color: var(--color-gray-text);
  line-height: 1.6;
  margin-bottom: 8px;
}

.editorial-link {
  font-size: 13px;
  font-weight: 700;
  color: var(--color-navy);
}

.editorial-link:hover {
  color: var(--color-accent);
}

/* ---------- 侧栏通用 ---------- */
.aside-title,
.related-title,
.sidebar-title {
  font-size: 16px;
  font-weight: 700;
  color: var(--color-navy);
  padding-bottom: 10px;
  border-bottom: 2px solid var(--color-accent);
  margin-bottom: 16px;
}

.aside-card,
.sidebar-card {
  background-color: var(--color-white);
  border: 1px solid var(--color-line);
  border-radius: var(--radius-md);
  padding: 22px 20px;
  margin-bottom: 24px;
}

.aside-list li,
.sidebar-list li,
.related-links li {
  margin-bottom: 4px;
}

.aside-list li a,
.sidebar-list li a,
.related-links li a {
  display: block;
  padding: 8px 0;
  font-size: 14px;
  color: var(--color-ink);
  border-bottom: 1px dashed var(--color-line);
  transition: color 0.2s ease, padding-left 0.2s ease;
}

.aside-list li:last-child a,
.sidebar-list li:last-child a,
.related-links li:last-child a {
  border-bottom: none;
}

.aside-list li a:hover,
.sidebar-list li a:hover,
.related-links li a:hover {
  color: var(--color-accent);
  padding-left: 6px;
}

/* ---------- 文本链接 ---------- */
.text-link {
  font-size: 14px;
  font-weight: 700;
  color: var(--color-accent);
  display: inline-flex;
  align-items: center;
  gap: 4px;
}

.text-link:hover {
  text-decoration: underline;
}

/* ----------------------------------------------------------
   Pages — 首页
   ---------------------------------------------------------- */
.home-main {
  width: 100%;
}

/* ---------- 首屏 hero ---------- */
.hero-section {
  background-color: var(--color-white);
  border-bottom: 1px solid var(--color-line);
}

.hero-grid {
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 32px var(--container-pad) 40px;
  display: grid;
  grid-template-columns: 2fr 1fr;
  gap: var(--card-gap);
  align-items: start;
}

/* ---------- 频道分类带 ---------- */
.channels-section {
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 44px var(--container-pad) 8px;
}

.section-header {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  margin-bottom: 18px;
  gap: 16px;
}

.section-header .section-title {
  margin-bottom: 0;
}

.section-more {
  font-size: 13px;
  font-weight: 600;
  color: var(--color-accent);
  flex-shrink: 0;
}

.section-more:hover {
  text-decoration: underline;
}

/* ---------- 最新资讯 ---------- */
.latest-section {
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 40px var(--container-pad) 8px;
}

/* ---------- 专题推荐 ---------- */
.topics-section {
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 40px var(--container-pad) 8px;
}

.topics-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: var(--card-gap);
}

/* ---------- 编辑推荐 ---------- */
.editorial-section {
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 40px var(--container-pad) 8px;
}

/* ---------- 信息来源与反馈 ---------- */
.source-section {
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 40px var(--container-pad) 56px;
}

.source-content {
  background-color: var(--color-white);
  border: 1px solid var(--color-line);
  border-radius: var(--radius-md);
  padding: 24px 28px;
}

.source-content p {
  font-size: 14px;
  color: var(--color-gray-text);
  line-height: 1.7;
  margin-bottom: 10px;
}

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

/* ----------------------------------------------------------
   Pages — 频道分类页
   ---------------------------------------------------------- */

/* 侧栏在左的布局 */
.page-layout.sidebar-left {
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 24px var(--container-pad) 8px;
  display: grid;
  grid-template-columns: 260px 1fr;
  gap: 32px;
  align-items: start;
}

.channel-aside {
  background-color: var(--color-white);
  border: 1px solid var(--color-line);
  border-radius: var(--radius-md);
  padding: 22px 20px;
  position: sticky;
  top: calc(var(--header-h) + 16px);
}

.channel-index-list li a {
  display: block;
  padding: 9px 12px;
  font-size: 14px;
  font-weight: 600;
  color: var(--color-navy);
  border-left: 3px solid transparent;
  transition: all 0.2s ease;
}

.channel-index-list li a:hover {
  color: var(--color-accent);
  border-left-color: var(--color-accent);
  background-color: var(--color-bg);
}

.channel-section {
  margin-bottom: 40px;
  padding-bottom: 32px;
  border-bottom: 1px solid var(--color-line);
}

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

.channel-title {
  font-size: 20px;
  font-weight: 700;
  color: var(--color-ink);
  margin-bottom: 8px;
  padding-left: 14px;
  position: relative;
}

.channel-title::before {
  content: "";
  position: absolute;
  left: 0;
  top: 5px;
  bottom: 5px;
  width: 4px;
  background-color: var(--color-accent);
  border-radius: 2px;
}

.channel-desc {
  font-size: 14px;
  color: var(--color-gray-text);
  margin-bottom: 18px;
}

.channel-preview {
  display: grid;
  grid-template-columns: 1fr 1fr 1fr;
  gap: 20px;
}

.preview-item {
  background-color: var(--color-white);
  border: 1px solid var(--color-line);
  border-radius: var(--radius-sm);
  padding: 18px 18px 16px;
  transition: box-shadow 0.2s ease;
}

.preview-item:hover {
  box-shadow: 0 3px 10px rgba(0, 0, 0, 0.06);
}

.preview-item h3 {
  font-size: 15px;
  font-weight: 700;
  line-height: 1.45;
  margin-bottom: 6px;
}

.preview-meta {
  font-size: 12px;
  color: var(--color-gray-mid);
  margin-bottom: 8px;
}

.preview-text {
  font-size: 13px;
  color: var(--color-gray-text);
  line-height: 1.6;
  display: -webkit-box;
  -webkit-line-clamp: 3;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

/* 频道概览 */
.channel-overview {
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 32px var(--container-pad) 56px;
}

.overview-title {
  font-size: 22px;
  font-weight: 700;
  margin-bottom: 12px;
  padding-left: 14px;
  position: relative;
}

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

.overview-desc {
  font-size: 15px;
  color: var(--color-gray-text);
  line-height: 1.7;
  margin-bottom: 24px;
  max-width: 760px;
}

.overview-desc a {
  color: var(--color-accent);
  font-weight: 600;
}

.overview-desc a:hover {
  text-decoration: underline;
}

.overview-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--card-gap);
}

.overview-card {
  background-color: var(--color-white);
  border: 1px solid var(--color-line);
  border-radius: var(--radius-md);
  overflow: hidden;
  transition: box-shadow 0.2s ease;
}

.overview-card:hover {
  box-shadow: 0 4px 14px rgba(0, 0, 0, 0.07);
}

.overview-media {
  aspect-ratio: 16 / 10;
  background-color: var(--color-gray-light);
  overflow: hidden;
}

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

.overview-card-title {
  font-size: 16px;
  font-weight: 700;
  padding: 16px 18px 4px;
}

.overview-card-text {
  font-size: 13px;
  color: var(--color-gray-text);
  line-height: 1.6;
  padding: 0 18px 18px;
}

/* ----------------------------------------------------------
   Pages — 内容专题页
   ---------------------------------------------------------- */
.topics-grid-inner {
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 24px var(--container-pad) 8px;
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--card-gap);
}

.topics-summary {
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 40px var(--container-pad) 8px;
}

.summary-list {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 20px;
}

.summary-item {
  background-color: var(--color-white);
  border: 1px solid var(--color-line);
  border-radius: var(--radius-sm);
  padding: 20px 22px;
  display: flex;
  gap: 18px;
  transition: box-shadow 0.2s ease;
}

.summary-item:hover {
  box-shadow: 0 3px 12px rgba(0, 0, 0, 0.06);
}

.summary-index {
  font-size: 26px;
  font-weight: 800;
  color: var(--color-accent);
  line-height: 1;
  flex-shrink: 0;
  font-style: italic;
}

.summary-title {
  font-size: 16px;
  font-weight: 700;
  margin-bottom: 6px;
  line-height: 1.4;
}

.summary-text {
  font-size: 13px;
  color: var(--color-gray-text);
  line-height: 1.6;
  margin-bottom: 8px;
}

.summary-link {
  font-size: 13px;
  font-weight: 700;
  color: var(--color-accent);
}

.summary-link:hover {
  text-decoration: underline;
}

.topics-related {
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 32px var(--container-pad) 56px;
}

/* ----------------------------------------------------------
   Pages — 实用指南页
   ---------------------------------------------------------- */

/* guide.html 特殊布局：main 在前、aside 在后的双栏 */
.layout-shell.guide-layout {
  display: grid;
  grid-template-columns: 1fr 300px;
  gap: 40px;
  align-items: start;
  padding-top: 24px;
  padding-bottom: 56px;
}

.guide-aside {
  position: sticky;
  top: calc(var(--header-h) + 16px);
}

.guide-section {
  margin-bottom: 40px;
  padding-bottom: 36px;
  border-bottom: 1px solid var(--color-line);
}

.guide-section:last-child {
  border-bottom: none;
}

.guide-step-list {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 20px;
}

.guide-step {
  background-color: var(--color-white);
  border: 1px solid var(--color-line);
  border-radius: var(--radius-md);
  padding: 24px 24px 22px;
  display: flex;
  gap: 18px;
  transition: box-shadow 0.2s ease;
}

.guide-step:hover {
  box-shadow: 0 3px 12px rgba(0, 0, 0, 0.06);
}

.guide-step .step-number {
  font-size: 30px;
  font-weight: 800;
  color: var(--color-accent);
  line-height: 1;
  flex-shrink: 0;
  font-style: italic;
}

.guide-step .step-content h3 {
  font-size: 16px;
  font-weight: 700;
  margin-bottom: 6px;
}

.guide-step .step-content p {
  font-size: 14px;
  color: var(--color-gray-text);
  line-height: 1.65;
}

.guide-media {
  margin: 32px 0;
  border-radius: var(--radius-md);
  overflow: hidden;
  background-color: var(--color-gray-light);
}

.guide-media img {
  width: 100%;
  aspect-ratio: 16 / 8;
  object-fit: cover;
}

.guide-media figcaption {
  font-size: 13px;
  color: var(--color-gray-mid);
  padding: 10px 16px;
  background-color: var(--color-white);
  border: 1px solid var(--color-line);
  border-top: none;
}

.problem-list {
  display: grid;
  grid-template-columns: 1fr 1fr 1fr;
  gap: 20px;
}

.problem-item {
  background-color: var(--color-white);
  border: 1px solid var(--color-line);
  border-top: 3px solid var(--color-navy);
  border-radius: var(--radius-sm);
  padding: 20px 20px 18px;
}

.problem-title {
  font-size: 15px;
  font-weight: 700;
  margin-bottom: 8px;
}

.problem-item p {
  font-size: 13px;
  color: var(--color-gray-text);
  line-height: 1.65;
}

.problem-item p a {
  color: var(--color-accent);
  font-weight: 600;
}

.problem-item p a:hover {
  text-decoration: underline;
}

/* ----------------------------------------------------------
   Pages — 深度解读页
   ---------------------------------------------------------- */

/* insight.html 布局：main 在前、sidebar 在后 */
.layout-shell.insight-layout {
  display: grid;
  grid-template-columns: 1fr 300px;
  gap: 40px;
  align-items: start;
  padding-top: 24px;
  padding-bottom: 56px;
}

.sidebar {
  position: sticky;
  top: calc(var(--header-h) + 16px);
}

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

.insight-item {
  background-color: var(--color-white);
  border: 1px solid var(--color-line);
  border-radius: var(--radius-md);
  overflow: hidden;
  margin-bottom: 24px;
  display: flex;
  transition: box-shadow 0.2s ease;
}

.insight-item:hover {
  box-shadow: 0 4px 14px rgba(0, 0, 0, 0.07);
}

.insight-media {
  width: 240px;
  flex-shrink: 0;
  background-color: var(--color-gray-light);
  overflow: hidden;
}

.insight-media img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  aspect-ratio: 4 / 3;
}

.insight-content {
  padding: 22px 24px;
  flex: 1;
}

.insight-title {
  font-size: 18px;
  font-weight: 700;
  margin-bottom: 6px;
  line-height: 1.4;
}

.insight-title a {
  color: var(--color-ink);
}

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

.insight-meta {
  font-size: 12px;
  color: var(--color-gray-mid);
  margin-bottom: 10px;
}

.insight-summary {
  font-size: 14px;
  color: var(--color-gray-text);
  line-height: 1.65;
  margin-bottom: 12px;
  display: -webkit-box;
  -webkit-line-clamp: 3;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

/* 分析框架 */
.framework-section {
  margin-bottom: 40px;
}

.framework-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
  margin-bottom: 20px;
}

.framework-card {
  background-color: var(--color-white);
  border: 1px solid var(--color-line);
  border-radius: var(--radius-md);
  padding: 22px 20px;
  text-align: left;
}

.framework-number {
  display: block;
  font-size: 24px;
  font-weight: 800;
  color: var(--color-accent);
  margin-bottom: 10px;
  font-style: italic;
}

.framework-name {
  font-size: 15px;
  font-weight: 700;
  margin-bottom: 6px;
}

.framework-desc {
  font-size: 13px;
  color: var(--color-gray-text);
  line-height: 1.6;
}

.framework-note {
  font-size: 14px;
  color: var(--color-gray-text);
  line-height: 1.7;
  background-color: var(--color-white);
  border-left: 4px solid var(--color-accent);
  border-radius: var(--radius-sm);
  padding: 16px 20px;
}

.framework-note a {
  color: var(--color-accent);
  font-weight: 600;
}

.framework-note a:hover {
  text-decoration: underline;
}

/* ----------------------------------------------------------
   Pages — 404 页
   ---------------------------------------------------------- */
.error-main {
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 60vh;
  padding: 48px var(--container-pad);
}

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

.error-code {
  font-size: 88px;
  font-weight: 800;
  color: var(--color-accent);
  line-height: 1;
  display: block;
  margin-bottom: 16px;
  font-style: italic;
}

.error-title {
  font-size: 28px;
  font-weight: 700;
  margin-bottom: 12px;
}

.error-desc {
  font-size: 15px;
  color: var(--color-gray-text);
  line-height: 1.7;
  margin-bottom: 10px;
}

.error-btn {
  display: inline-block;
  margin-top: 20px;
  padding: 12px 32px;
  background-color: var(--color-accent);
  color: var(--color-white);
  font-size: 15px;
  font-weight: 700;
  border-radius: var(--radius-sm);
  transition: background-color 0.2s ease;
}

.error-btn:hover {
  background-color: var(--color-navy);
  color: var(--color-white);
}

/* ----------------------------------------------------------
   Responsive — 响应式断点
   ---------------------------------------------------------- */
@media (max-width: 1024px) {
  :root {
    --section-gap: 40px;
  }

  /* 专题页 3 列 → 2 列 */
  .topics-grid-inner {
    grid-template-columns: repeat(2, 1fr);
  }

  /* 编辑推荐 3 列 → 2 列 */
  .editorial-list {
    grid-template-columns: 1fr 1fr;
  }

  /* 分析框架 4 列 → 2 列 */
  .framework-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  /* 频道预览 3 列 → 2 列 */
  .channel-preview {
    grid-template-columns: 1fr 1fr;
  }

  /* 概览 3 列 → 2 列 */
  .overview-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  /* 问题列表 3 列 → 2 列 */
  .problem-list {
    grid-template-columns: 1fr 1fr;
  }

  /* 首页 hero 2 列 → 1 列 */
  .hero-grid {
    grid-template-columns: 1fr;
  }

  .flash-column {
    margin-top: 0;
  }
}

@media (max-width: 768px) {
  :root {
    --container-pad: 16px;
    --header-h: 60px;
    --section-gap: 32px;
  }

  /* ---------- 导航（移动端汉堡） ---------- */
  .nav-toggle {
    display: flex;
  }

  .site-nav {
    position: absolute;
    top: var(--header-h);
    left: 0;
    right: 0;
    background-color: var(--color-white);
    border-bottom: 1px solid var(--color-line);
    box-shadow: 0 6px 16px rgba(0, 0, 0, 0.08);
    margin-left: 0;
  }

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

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

  .nav-list li a {
    padding: 14px 12px;
    font-size: 16px;
    border-radius: var(--radius-sm);
    border-bottom: 1px solid var(--color-line);
  }

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

  .nav-list li a.is-current {
    color: var(--color-accent);
    background-color: rgba(192, 57, 43, 0.06);
  }

  /* ---------- 汉堡按钮动画状态 ---------- */
  .nav-toggle[aria-expanded="true"] .nav-toggle-bar:nth-child(1) {
    transform: translateY(7px) rotate(45deg);
  }

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

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

  /* ---------- 页脚 ---------- */
  .footer-inner {
    grid-template-columns: 1fr;
    gap: 32px;
    padding: 36px var(--container-pad) 24px;
  }

  .footer-links {
    grid-template-columns: repeat(3, 1fr);
    gap: 16px;
  }

  /* ---------- 面包屑 ---------- */
  .breadcrumb {
    padding: 14px var(--container-pad) 0;
  }

  /* ---------- 页面标题 ---------- */
  .page-header {
    padding: 24px var(--container-pad) 4px;
  }

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

  /* ---------- 首页 ---------- */
  .hero-grid {
    padding: 20px var(--container-pad) 28px;
    gap: 20px;
  }

  .feature-content {
    padding: 20px 20px 24px;
  }

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

  .channels-section,
  .latest-section,
  .topics-section,
  .editorial-section,
  .source-section {
    padding: 32px var(--container-pad) 4px;
  }

  .news-list {
    grid-template-columns: 1fr;
  }

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

  .editorial-list {
    grid-template-columns: 1fr;
  }

  .editorial-item {
    padding: 16px 16px 14px;
  }

  .source-section {
    padding-bottom: 40px;
  }

  /* ---------- 频道分类页 ---------- */
  .page-layout.sidebar-left {
    grid-template-columns: 1fr;
    gap: 24px;
    padding: 20px var(--container-pad) 4px;
  }

  .channel-aside {
    position: static;
    order: 2;
  }

  .channel-content {
    order: 1;
  }

  .channel-preview {
    grid-template-columns: 1fr;
    gap: 16px;
  }

  .channel-overview {
    padding: 24px var(--container-pad) 40px;
  }

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

  /* ---------- 内容专题页 ---------- */
  .topics-grid-inner {
    grid-template-columns: 1fr;
    padding: 20px var(--container-pad) 4px;
  }

  .topics-summary {
    padding: 28px var(--container-pad) 4px;
  }

  .summary-list {
    grid-template-columns: 1fr;
  }

  .topics-related {
    padding: 24px var(--container-pad) 40px;
  }

  /* ---------- 实用指南页 ---------- */
  .layout-shell.guide-layout {
    grid-template-columns: 1fr;
    gap: 0;
    padding-top: 16px;
  }

  .guide-aside {
    position: static;
    margin-top: 8px;
  }

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

  .problem-list {
    grid-template-columns: 1fr;
  }

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

  /* ---------- 深度解读页 ---------- */
  .layout-shell.insight-layout {
    grid-template-columns: 1fr;
    gap: 0;
    padding-top: 16px;
  }

  .sidebar {
    position: static;
    margin-top: 8px;
  }

  .insight-item {
    flex-direction: column;
  }

  .insight-media {
    width: 100%;
  }

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

  .framework-grid {
    grid-template-columns: 1fr 1fr;
    gap: 14px;
  }

  /* ---------- 404 ---------- */
  .error-code {
    font-size: 64px;
  }

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

@media (max-width: 480px) {
  .brand-name {
    font-size: 22px;
  }

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

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

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

  .summary-item {
    flex-direction: column;
    gap: 8px;
  }

  .guide-step {
    padding: 18px 16px;
  }

  .flash-list li a {
    font-size: 13px;
  }

  .news-headline {
    font-size: 15px;
  }

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