/* =========================================================
   Base / Reset
   ========================================================= */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

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

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
  font-size: 16px;
  line-height: 1.7;
  color: #333333;
  background-color: #f5f5f5;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

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

a {
  color: #1a2a3a;
  text-decoration: none;
  transition: color 0.2s ease;
}

a:hover {
  color: #ff7f2a;
}

ul, ol {
  list-style: none;
}

button {
  font-family: inherit;
  border: none;
  background: none;
  cursor: pointer;
}

time {
  font-family: "SF Mono", "Consolas", "Menlo", "Courier New", monospace;
  font-size: 0.875rem;
}

/* =========================================================
   Layout / Shell
   ========================================================= */
.site-header {
  background-color: #1a2a3a;
  border-bottom: 3px solid #ff7f2a;
  position: sticky;
  top: 0;
  z-index: 100;
}

.header-inner {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 20px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  min-height: 64px;
}

.brand {
  display: flex;
  flex-direction: column;
  line-height: 1.2;
  padding: 8px 0;
}

.brand-name {
  font-size: 1.25rem;
  font-weight: 700;
  color: #ffffff;
  letter-spacing: 0;
}

.brand-slogan {
  font-size: 0.75rem;
  color: rgba(255, 255, 255, 0.7);
}

.nav-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 44px;
  height: 44px;
  padding: 10px;
  border-radius: 4px;
}

.nav-toggle-bar {
  display: block;
  width: 24px;
  height: 2px;
  background-color: #ffffff;
  border-radius: 1px;
  transition: transform 0.2s ease, opacity 0.2s ease;
}

.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);
}

.site-nav {
  display: block;
}

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

.nav-list li a {
  display: block;
  padding: 10px 16px;
  font-size: 0.9375rem;
  font-weight: 500;
  color: rgba(255, 255, 255, 0.85);
  border-radius: 4px;
  transition: background-color 0.2s ease, color 0.2s ease;
}

.nav-list li a:hover {
  color: #ffffff;
  background-color: rgba(255, 255, 255, 0.1);
}

.nav-list li a.is-current {
  color: #ffffff;
  background-color: #ff7f2a;
  font-weight: 600;
}

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

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 20px;
}

/* =========================================================
   Footer
   ========================================================= */
.site-footer {
  background-color: #1a2a3a;
  color: rgba(255, 255, 255, 0.8);
  margin-top: auto;
}

.footer-inner {
  max-width: 1200px;
  margin: 0 auto;
  padding: 48px 20px 24px;
  display: grid;
  grid-template-columns: 2fr 3fr;
  gap: 40px;
}

.footer-brand-name {
  font-size: 1.125rem;
  font-weight: 700;
  color: #ffffff;
  margin-bottom: 8px;
}

.footer-brand-desc {
  font-size: 0.875rem;
  line-height: 1.6;
  color: rgba(255, 255, 255, 0.6);
}

.footer-links {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
}

.footer-col-title {
  font-size: 0.875rem;
  font-weight: 600;
  color: #ffffff;
  margin-bottom: 12px;
}

.footer-col ul li {
  margin-bottom: 6px;
}

.footer-col ul li a {
  font-size: 0.8125rem;
  color: rgba(255, 255, 255, 0.6);
  line-height: 1.5;
}

.footer-col ul li a:hover {
  color: #ff7f2a;
}

.footer-bottom {
  grid-column: 1 / -1;
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  padding-top: 16px;
  margin-top: 8px;
}

.footer-copyright {
  font-size: 0.8125rem;
  color: rgba(255, 255, 255, 0.5);
}

/* =========================================================
   Breadcrumb
   ========================================================= */
.breadcrumb {
  max-width: 1200px;
  margin: 0 auto;
  padding: 16px 20px 0;
  font-size: 0.8125rem;
  color: #666666;
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 6px;
}

.breadcrumb a {
  color: #1a2a3a;
}

.breadcrumb a:hover {
  color: #ff7f2a;
}

.breadcrumb-sep {
  color: #999999;
  margin: 0 2px;
}

.breadcrumb-current {
  color: #666666;
  font-weight: 500;
}

/* =========================================================
   Inner Page Header
   ========================================================= */
.inner-main {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 20px 48px;
}

.page-header {
  padding: 24px 0 32px;
  border-bottom: 1px solid #e5e5e5;
  margin-bottom: 32px;
}

.page-title {
  font-size: 2rem;
  font-weight: 700;
  color: #1a2a3a;
  line-height: 1.3;
  margin-bottom: 8px;
}

.page-description {
  font-size: 0.9375rem;
  color: #666666;
  max-width: 720px;
}

/* =========================================================
   Index / Home
   ========================================================= */
.home-main {
  background-color: #f5f5f5;
}

/* Hero */
.hero-section {
  background-color: #1a2a3a;
  padding: 48px 0;
}

.hero-section > .hero-content,
.hero-section > .hero-media {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 20px;
}

.hero-section {
  display: grid;
  grid-template-columns: 1fr 1fr;
  align-items: center;
  gap: 40px;
}

.hero-title {
  font-size: 2.25rem;
  font-weight: 700;
  color: #ffffff;
  line-height: 1.3;
  margin-bottom: 16px;
}

.hero-summary {
  font-size: 1rem;
  color: rgba(255, 255, 255, 0.8);
  line-height: 1.7;
  margin-bottom: 24px;
  max-width: 520px;
}

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

.btn {
  display: inline-block;
  padding: 10px 24px;
  font-size: 0.9375rem;
  font-weight: 600;
  border-radius: 6px;
  transition: background-color 0.2s ease, color 0.2s ease, border-color 0.2s ease;
}

.btn-primary {
  background-color: #ff7f2a;
  color: #ffffff;
  border: 2px solid #ff7f2a;
}

.btn-primary:hover {
  background-color: #e66a14;
  border-color: #e66a14;
  color: #ffffff;
}

.btn-secondary {
  background-color: transparent;
  color: #ffffff;
  border: 2px solid rgba(255, 255, 255, 0.6);
}

.btn-secondary:hover {
  border-color: #ffffff;
  color: #ffffff;
}

.hero-figure {
  width: 100%;
  border-radius: 8px;
  overflow: hidden;
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.3);
}

.hero-figure img {
  width: 100%;
  height: 100%;
  min-height: 260px;
  max-height: 360px;
  object-fit: cover;
}

/* Section Head */
.section-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 24px;
}

.section-title {
  font-size: 1.375rem;
  font-weight: 700;
  color: #1a2a3a;
  position: relative;
  padding-left: 14px;
}

.section-title::before {
  content: "";
  position: absolute;
  left: 0;
  top: 4px;
  bottom: 4px;
  width: 4px;
  background-color: #ff7f2a;
  border-radius: 2px;
}

.section-more {
  font-size: 0.875rem;
  color: #1a2a3a;
  display: inline-flex;
  align-items: center;
  gap: 4px;
  font-weight: 500;
}

.section-more span {
  font-size: 1rem;
}

.section-more:hover {
  color: #ff7f2a;
}

/* Channel Strip */
.channel-strip {
  padding: 40px 0;
  background-color: #ffffff;
}

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

.channel-tag {
  display: inline-block;
  padding: 8px 20px;
  background-color: #f5f5f5;
  border: 1px solid #e0e0e0;
  border-radius: 6px;
  font-size: 0.9375rem;
  font-weight: 500;
  color: #1a2a3a;
  transition: background-color 0.2s ease, border-color 0.2s ease, color 0.2s ease;
}

.channel-tag:hover {
  background-color: #ff7f2a;
  border-color: #ff7f2a;
  color: #ffffff;
}

/* Latest News */
.latest-news {
  padding: 48px 0;
}

.news-timeline {
  border-left: 2px solid #e0e0e0;
  padding-left: 24px;
  display: flex;
  flex-direction: column;
  gap: 0;
}

.news-item {
  position: relative;
  padding: 16px 0;
  border-bottom: 1px solid #eeeeee;
}

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

.news-item::before {
  content: "";
  position: absolute;
  left: -31px;
  top: 24px;
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background-color: #ffffff;
  border: 3px solid #ff7f2a;
}

.news-date {
  display: block;
  color: #999999;
  margin-bottom: 6px;
}

.news-title {
  font-size: 1.0625rem;
  font-weight: 600;
  color: #1a2a3a;
  margin-bottom: 4px;
  line-height: 1.4;
}

.news-title a {
  color: inherit;
}

.news-title a:hover {
  color: #ff7f2a;
}

.news-summary {
  font-size: 0.875rem;
  color: #666666;
  line-height: 1.6;
}

/* Featured Topics */
.featured-topics {
  padding: 48px 0;
  background-color: #ffffff;
}

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

.topic-card {
  background-color: #f5f5f5;
  border-radius: 8px;
  overflow: hidden;
  border: 1px solid #e8e8e8;
  transition: box-shadow 0.2s ease, transform 0.2s ease;
}

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

.topic-card-media {
  width: 100%;
  overflow: hidden;
}

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

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

.topic-card-title {
  font-size: 1.125rem;
  font-weight: 600;
  color: #1a2a3a;
  margin-bottom: 8px;
}

.topic-card-summary {
  font-size: 0.875rem;
  color: #666666;
  line-height: 1.6;
  margin-bottom: 12px;
}

.topic-card-link {
  font-size: 0.875rem;
  font-weight: 600;
  color: #ff7f2a;
  display: inline-flex;
  align-items: center;
  gap: 4px;
}

.topic-card-link::after {
  content: "→";
  transition: transform 0.2s ease;
}

.topic-card-link:hover {
  color: #e66a14;
}

.topic-card-link:hover::after {
  transform: translateX(3px);
}

/* Editor Picks */
.editor-picks {
  padding: 48px 0;
}

.pick-list {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.pick-item {
  display: flex;
  gap: 16px;
  align-items: flex-start;
  background-color: #ffffff;
  border-radius: 8px;
  padding: 20px;
  border: 1px solid #e8e8e8;
  transition: box-shadow 0.2s ease;
}

.pick-item:hover {
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.06);
}

.pick-index {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  flex-shrink: 0;
  background-color: #1a2a3a;
  color: #ffffff;
  font-weight: 700;
  font-size: 1rem;
  border-radius: 6px;
  font-family: "SF Mono", "Consolas", "Menlo", monospace;
}

.pick-content {
  flex: 1;
}

.pick-title {
  font-size: 1rem;
  font-weight: 600;
  color: #1a2a3a;
  margin-bottom: 4px;
}

.pick-title a {
  color: inherit;
}

.pick-title a:hover {
  color: #ff7f2a;
}

.pick-reason {
  font-size: 0.875rem;
  color: #666666;
  line-height: 1.6;
}

/* Source Note */
.source-note {
  padding: 40px 0 56px;
  background-color: #ffffff;
}

.source-note .section-title {
  margin-bottom: 20px;
}

.source-note-content {
  background-color: #f5f5f5;
  border-left: 4px solid #ff7f2a;
  padding: 20px 24px;
  border-radius: 0 6px 6px 0;
}

.source-note-content p {
  font-size: 0.875rem;
  color: #555555;
  line-height: 1.7;
  margin-bottom: 8px;
}

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

/* =========================================================
   Channels Page
   ========================================================= */
.channel-index {
  margin-bottom: 48px;
}

.channel-index h2,
.channel-explanation h2 {
  font-size: 1.375rem;
  font-weight: 700;
  color: #1a2a3a;
  margin-bottom: 24px;
  position: relative;
  padding-left: 14px;
}

.channel-index h2::before,
.channel-explanation h2::before {
  content: "";
  position: absolute;
  left: 0;
  top: 4px;
  bottom: 4px;
  width: 4px;
  background-color: #ff7f2a;
  border-radius: 2px;
}

.channel-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
}

.channel-card {
  background-color: #ffffff;
  border: 1px solid #e8e8e8;
  border-radius: 8px;
  padding: 24px;
  display: flex;
  gap: 16px;
  align-items: flex-start;
  transition: box-shadow 0.2s ease, border-color 0.2s ease;
}

.channel-card:hover {
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.06);
  border-color: #ff7f2a;
}

.channel-icon {
  width: 44px;
  height: 44px;
  flex-shrink: 0;
  background-color: #1a2a3a;
  border-radius: 6px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.25rem;
  color: #ffffff;
  font-weight: 700;
  font-family: "SF Mono", "Consolas", "Menlo", monospace;
}

.channel-card-body {
  flex: 1;
}

.channel-name {
  font-size: 1.0625rem;
  font-weight: 600;
  color: #1a2a3a;
  margin-bottom: 6px;
}

.channel-desc {
  font-size: 0.875rem;
  color: #666666;
  line-height: 1.6;
}

/* Channel Explanation */
.channel-explanation {
  background-color: #ffffff;
  border-radius: 8px;
  padding: 32px;
  border: 1px solid #e8e8e8;
}

.explanation-content {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 32px;
  align-items: center;
}

.explanation-media {
  width: 100%;
  border-radius: 8px;
  overflow: hidden;
}

.explanation-media img {
  width: 100%;
  height: 220px;
  object-fit: cover;
}

.explanation-text p {
  font-size: 0.9375rem;
  color: #444444;
  line-height: 1.7;
  margin-bottom: 12px;
}

.explanation-text p:last-child {
  margin-bottom: 0;
}

/* =========================================================
   Topic Page
   ========================================================= */
.page-layout {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 20px 48px;
  display: grid;
  grid-template-columns: 1fr 300px;
  gap: 32px;
  align-items: start;
}

.page-layout .inner-main {
  max-width: none;
  padding: 0;
}

/* Topic Intro */
.topic-intro {
  margin-bottom: 48px;
}

.topic-intro .section-title {
  margin-bottom: 20px;
}

.topic-intro-content {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 24px;
  align-items: start;
}

.topic-intro-media {
  width: 100%;
  border-radius: 8px;
  overflow: hidden;
}

.topic-intro-media img {
  width: 100%;
  height: 240px;
  object-fit: cover;
}

.topic-intro-media figcaption {
  padding: 8px 12px;
  font-size: 0.8125rem;
  color: #888888;
  background-color: #f5f5f5;
}

.topic-intro-text p {
  font-size: 0.9375rem;
  color: #444444;
  line-height: 1.7;
  margin-bottom: 12px;
}

.topic-intro-text p:last-child {
  margin-bottom: 0;
}

/* Timeline */
.topic-timeline {
  margin-bottom: 48px;
}

.section-desc {
  font-size: 0.9375rem;
  color: #666666;
  margin-bottom: 24px;
}

.timeline-list {
  position: relative;
  padding-left: 24px;
  border-left: 2px solid #e0e0e0;
}

.timeline-item {
  position: relative;
  padding: 0 0 28px;
}

.timeline-item:last-child {
  padding-bottom: 0;
}

.timeline-item::before {
  content: "";
  position: absolute;
  left: -31px;
  top: 4px;
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background-color: #ffffff;
  border: 3px solid #ff7f2a;
}

.timeline-date {
  display: inline-block;
  background-color: #1a2a3a;
  color: #ffffff;
  font-size: 0.8125rem;
  padding: 3px 10px;
  border-radius: 4px;
  margin-bottom: 8px;
  font-weight: 500;
}

.timeline-content h3 {
  font-size: 1rem;
  font-weight: 600;
  color: #1a2a3a;
  margin-bottom: 4px;
}

.timeline-content p {
  font-size: 0.875rem;
  color: #555555;
  line-height: 1.6;
}

/* Key Info */
.topic-keyinfo {
  margin-bottom: 48px;
}

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

.keyinfo-item {
  background-color: #ffffff;
  border: 1px solid #e8e8e8;
  border-radius: 8px;
  padding: 16px 20px;
  display: flex;
  gap: 12px;
  align-items: flex-start;
}

.keyinfo-label {
  display: inline-block;
  background-color: #ff7f2a;
  color: #ffffff;
  font-size: 0.75rem;
  font-weight: 600;
  padding: 2px 8px;
  border-radius: 4px;
  white-space: nowrap;
  flex-shrink: 0;
  margin-top: 2px;
}

.keyinfo-item p {
  font-size: 0.875rem;
  color: #444444;
  line-height: 1.6;
}

/* Related */
.topic-related {
  margin-bottom: 48px;
}

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

.related-card {
  background-color: #ffffff;
  border: 1px solid #e8e8e8;
  border-radius: 8px;
  padding: 20px;
  transition: box-shadow 0.2s ease;
}

.related-card:hover {
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.06);
}

.related-card h3 {
  font-size: 0.9375rem;
  font-weight: 600;
  color: #1a2a3a;
  margin-bottom: 6px;
  line-height: 1.4;
}

.related-card p {
  font-size: 0.8125rem;
  color: #666666;
  line-height: 1.6;
  margin-bottom: 10px;
}

.related-card a {
  font-size: 0.8125rem;
  font-weight: 600;
  color: #ff7f2a;
}

.related-card a:hover {
  color: #e66a14;
}

/* Topic Source */
.topic-source {
  background-color: #f5f5f5;
  border-left: 4px solid #ff7f2a;
  padding: 20px 24px;
  border-radius: 0 6px 6px 0;
}

.topic-source .section-title {
  margin-bottom: 12px;
  font-size: 1.125rem;
}

.topic-source p {
  font-size: 0.875rem;
  color: #555555;
  line-height: 1.7;
  margin-bottom: 8px;
}

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

/* Sidebar */
.sidebar {
  position: sticky;
  top: 80px;
}

.sidebar-inner {
  background-color: #ffffff;
  border-radius: 8px;
  border: 1px solid #e8e8e8;
  padding: 24px;
}

.sidebar-title {
  font-size: 1rem;
  font-weight: 700;
  color: #1a2a3a;
  margin-bottom: 16px;
  padding-bottom: 8px;
  border-bottom: 2px solid #ff7f2a;
}

.sidebar-list li {
  margin-bottom: 4px;
}

.sidebar-list li a {
  display: block;
  padding: 8px 10px;
  font-size: 0.875rem;
  color: #444444;
  border-radius: 4px;
  line-height: 1.5;
  transition: background-color 0.2s ease, color 0.2s ease;
}

.sidebar-list li a:hover {
  background-color: #f5f5f5;
  color: #ff7f2a;
}

/* =========================================================
   Insight Page
   ========================================================= */
.article-content {
  max-width: 800px;
}

.article-media {
  width: 100%;
  border-radius: 8px;
  overflow: hidden;
  margin-bottom: 24px;
}

.article-media img {
  width: 100%;
  height: 320px;
  object-fit: cover;
}

.article-media figcaption {
  padding: 8px 12px;
  font-size: 0.8125rem;
  color: #888888;
  background-color: #f5f5f5;
}

.content-section {
  margin-bottom: 32px;
}

.content-section h2 {
  font-size: 1.25rem;
  font-weight: 700;
  color: #1a2a3a;
  margin-bottom: 12px;
  padding-left: 14px;
  position: relative;
}

.content-section h2::before {
  content: "";
  position: absolute;
  left: 0;
  top: 4px;
  bottom: 4px;
  width: 4px;
  background-color: #ff7f2a;
  border-radius: 2px;
}

.content-section p {
  font-size: 0.9375rem;
  color: #444444;
  line-height: 1.8;
  margin-bottom: 12px;
}

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

/* Related Links */
.related-links {
  margin-top: 40px;
  padding-top: 20px;
  border-top: 1px solid #e5e5e5;
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 8px;
}

.related-links-label {
  font-size: 0.875rem;
  font-weight: 600;
  color: #1a2a3a;
  margin-right: 8px;
}

.related-links-item {
  display: inline-block;
  padding: 6px 14px;
  background-color: #f5f5f5;
  border-radius: 4px;
  font-size: 0.8125rem;
  color: #1a2a3a;
  transition: background-color 0.2s ease, color 0.2s ease;
}

.related-links-item:hover {
  background-color: #ff7f2a;
  color: #ffffff;
}

/* Sidebar Insight */
.sidebar-insight {
  display: flex;
  flex-direction: column;
  gap: 20px;
  position: sticky;
  top: 80px;
}

.sidebar-card {
  background-color: #ffffff;
  border-radius: 8px;
  border: 1px solid #e8e8e8;
  padding: 20px;
}

.toc-list li {
  margin-bottom: 2px;
}

.toc-list li a {
  display: block;
  padding: 8px 10px;
  font-size: 0.875rem;
  color: #444444;
  border-radius: 4px;
  line-height: 1.5;
  transition: background-color 0.2s ease, color 0.2s ease;
}

.toc-list li a:hover {
  background-color: #f5f5f5;
  color: #ff7f2a;
}

.sidebar-links li {
  margin-bottom: 2px;
}

.sidebar-links li a {
  display: block;
  padding: 8px 10px;
  font-size: 0.875rem;
  color: #444444;
  border-radius: 4px;
  line-height: 1.5;
  transition: background-color 0.2s ease, color 0.2s ease;
}

.sidebar-links li a:hover {
  background-color: #f5f5f5;
  color: #ff7f2a;
}

/* =========================================================
   Guide Page
   ========================================================= */
.guide-section {
  margin-bottom: 48px;
  background-color: #ffffff;
  border-radius: 8px;
  padding: 32px;
  border: 1px solid #e8e8e8;
}

.guide-section h2 {
  font-size: 1.375rem;
  font-weight: 700;
  color: #1a2a3a;
  margin-bottom: 16px;
  position: relative;
  padding-left: 14px;
}

.guide-section h2::before {
  content: "";
  position: absolute;
  left: 0;
  top: 4px;
  bottom: 4px;
  width: 4px;
  background-color: #ff7f2a;
  border-radius: 2px;
}

.section-lead {
  font-size: 0.9375rem;
  color: #666666;
  margin-bottom: 24px;
}

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

.method-step {
  background-color: #f5f5f5;
  border-radius: 8px;
  padding: 20px;
  border-left: 3px solid #ff7f2a;
}

.method-step h3 {
  font-size: 1rem;
  font-weight: 600;
  color: #1a2a3a;
  margin-bottom: 8px;
}

.method-step p {
  font-size: 0.875rem;
  color: #555555;
  line-height: 1.6;
}

.guide-figure {
  width: 100%;
  border-radius: 8px;
  overflow: hidden;
  margin-bottom: 20px;
}

.guide-figure img {
  width: 100%;
  height: 240px;
  object-fit: cover;
}

.guide-figure figcaption {
  padding: 8px 12px;
  font-size: 0.8125rem;
  color: #888888;
  background-color: #f5f5f5;
}

.guide-section > p {
  font-size: 0.9375rem;
  color: #444444;
  line-height: 1.8;
  margin-bottom: 12px;
}

.guide-section > p strong {
  color: #1a2a3a;
  font-weight: 600;
}

.feedback-options {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
  margin: 20px 0;
}

.feedback-item {
  background-color: #f5f5f5;
  border-radius: 8px;
  padding: 20px;
}

.feedback-item h3 {
  font-size: 0.9375rem;
  font-weight: 600;
  color: #1a2a3a;
  margin-bottom: 8px;
}

.feedback-item p {
  font-size: 0.8125rem;
  color: #555555;
  line-height: 1.6;
}

.feedback-note {
  font-size: 0.8125rem;
  color: #888888;
  border-top: 1px solid #e5e5e5;
  padding-top: 16px;
  margin-top: 8px;
}

/* =========================================================
   404 Page
   ========================================================= */
.error-main {
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 80px 20px;
  flex: 1;
}

.error-container {
  max-width: 560px;
  text-align: center;
  background-color: #ffffff;
  border-radius: 8px;
  border: 1px solid #e8e8e8;
  padding: 48px 40px;
}

.error-code {
  font-size: 4rem;
  font-weight: 700;
  color: #ff7f2a;
  font-family: "SF Mono", "Consolas", "Menlo", monospace;
  line-height: 1.2;
  margin-bottom: 8px;
}

.error-title {
  font-size: 1.5rem;
  font-weight: 700;
  color: #1a2a3a;
  margin-bottom: 12px;
}

.error-desc {
  font-size: 0.9375rem;
  color: #666666;
  line-height: 1.7;
  margin-bottom: 24px;
}

.error-btn {
  display: inline-block;
  padding: 10px 28px;
  background-color: #ff7f2a;
  color: #ffffff;
  font-size: 0.9375rem;
  font-weight: 600;
  border-radius: 6px;
  margin-bottom: 32px;
  transition: background-color 0.2s ease;
}

.error-btn:hover {
  background-color: #e66a14;
  color: #ffffff;
}

.error-links {
  border-top: 1px solid #e5e5e5;
  padding-top: 24px;
}

.error-links-title {
  font-size: 0.875rem;
  font-weight: 600;
  color: #1a2a3a;
  margin-bottom: 12px;
}

.error-links-list {
  display: flex;
  justify-content: center;
  flex-wrap: wrap;
  gap: 8px 16px;
}

.error-links-list li a {
  font-size: 0.875rem;
  color: #1a2a3a;
}

.error-links-list li a:hover {
  color: #ff7f2a;
}

/* =========================================================
   Responsive
   ========================================================= */
@media (max-width: 1024px) {
  .channel-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .related-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .page-layout {
    grid-template-columns: 1fr 260px;
    gap: 24px;
  }

  .hero-section {
    gap: 24px;
  }
}

@media (max-width: 768px) {
  .header-inner {
    min-height: 56px;
  }

  .nav-toggle {
    display: flex;
  }

  .site-nav {
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background-color: #1a2a3a;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.2);
  }

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

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

  .nav-list li a {
    padding: 12px 16px;
  }

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

  .hero-title {
    font-size: 1.75rem;
  }

  .hero-figure img {
    min-height: 200px;
    max-height: 260px;
  }

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

  .page-layout {
    grid-template-columns: 1fr;
  }

  .sidebar,
  .sidebar-insight {
    position: static;
    margin-top: 24px;
  }

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

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

  .explanation-content {
    grid-template-columns: 1fr;
  }

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

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

  .method-steps {
    grid-template-columns: 1fr;
  }

  .feedback-options {
    grid-template-columns: 1fr;
  }

  .footer-inner {
    grid-template-columns: 1fr;
    gap: 24px;
    padding-top: 32px;
  }

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

  .inner-main {
    padding: 0 16px 32px;
  }

  .page-header {
    padding: 16px 0 24px;
    margin-bottom: 24px;
  }

  .page-title {
    font-size: 1.5rem;
  }

  .breadcrumb {
    padding: 12px 16px 0;
  }

  .page-layout {
    padding: 0 16px 32px;
  }

  .guide-section {
    padding: 24px 20px;
  }

  .error-container {
    padding: 32px 24px;
  }
}

@media (max-width: 480px) {
  .header-inner {
    padding: 0 16px;
  }

  .brand-name {
    font-size: 1.125rem;
  }

  .brand-slogan {
    font-size: 0.6875rem;
  }

  .container {
    padding: 0 16px;
  }

  .hero-section > .hero-content,
  .hero-section > .hero-media {
    padding: 0 16px;
  }

  .hero-title {
    font-size: 1.5rem;
  }

  .hero-actions {
    flex-direction: column;
    gap: 8px;
  }

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

  .channel-tags {
    gap: 8px;
  }

  .channel-tag {
    padding: 6px 14px;
    font-size: 0.8125rem;
  }

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

  .news-item::before {
    left: -27px;
    width: 10px;
    height: 10px;
  }

  .pick-item {
    flex-direction: column;
    gap: 12px;
  }

  .pick-index {
    width: 32px;
    height: 32px;
    font-size: 0.875rem;
  }

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

  .footer-links {
    grid-template-columns: 1fr 1fr;
    gap: 16px;
  }

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

  .footer-inner {
    padding: 32px 16px 20px;
  }

  .article-media img {
    height: 200px;
  }

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

  .timeline-item::before {
    left: -27px;
    width: 10px;
    height: 10px;
  }

  .related-links {
    flex-direction: column;
    align-items: flex-start;
    gap: 6px;
  }

  .related-links-label {
    margin-right: 0;
  }

  .error-code {
    font-size: 3rem;
  }

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