@import url('https://fonts.googleapis.com/css2?family=Space+Grotesk:wght@700&display=swap');

/* ============================================
   CSS 变量 & 重置
   ============================================ */
:root {
  --c-blue: #c8e0f4;
  --c-pink: #f5e0e8;
  --c-dark: #171f26;
  --c-blue-dark: #a8c8e8;
  --c-blue-light: #e4f0fa;
  --c-pink-dark: #e8c8d8;
  --c-pink-light: #faf0f4;
  --c-dark-mid: #232d38;
  --c-dark-light: #2e3c4a;
  --c-text: #171f26;
  --c-text-muted: #4a5a6a;
  --c-text-inv: #f0f8ff;

  --shadow-neu-out:
    -5px -5px 15px rgba(255,255,255,0.85),
    5px 5px 15px rgba(100,140,180,0.25);
  --shadow-neu-in:
    inset -3px -3px 8px rgba(255,255,255,0.7),
    inset 3px 3px 8px rgba(100,140,180,0.3);
  --shadow-neu-press:
    inset -2px -2px 6px rgba(255,255,255,0.6),
    inset 2px 2px 10px rgba(100,140,180,0.4);
  --shadow-dark-out:
    -4px -4px 12px rgba(255,255,255,0.04),
    4px 4px 12px rgba(0,0,0,0.35);
  --shadow-card:
    -6px -6px 18px rgba(255,255,255,0.9),
    6px 6px 18px rgba(140,180,220,0.3);

  --radius-sm: 10px;
  --radius-md: 16px;
  --radius-lg: 24px;
  --radius-pill: 999px;

  --font-main: 'Space Grotesk', 'Helvetica Neue', Arial, sans-serif;
  --font-body: system-ui, -apple-system, 'Segoe UI', sans-serif;

  --header-h: 120px;
  --aside-w: 220px;
  --content-max: 860px;
  --page-max: 1200px;
  --gap: 1.5rem;
}

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

html {
  scroll-behavior: smooth;
  font-size: 17px;
  line-height: 1.65;
}

body {
  font-family: var(--font-body);
  background: var(--c-blue-light);
  color: var(--c-text);
  min-height: 100vh;
  display: flex;
}

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

a {
  color: inherit;
  text-decoration: none;
}

ul {
  list-style: none;
}

/* ============================================
   离屏侧边 aside（导航结构需要，视觉隐藏）
   ============================================ */
.site-aside {
  position: absolute;
  left: -9999px;
  width: 0;
  overflow: hidden;
  visibility: hidden;
}

/* ============================================
   整体布局
   ============================================ */
.page-wrapper {
  flex: 1;
  min-width: 0;
  display: flex;
  flex-direction: column;
}

/* ============================================
   顶部 Header（两行）
   ============================================ */
.site-header {
  background: linear-gradient(135deg, var(--c-blue) 0%, var(--c-blue-light) 100%);
  box-shadow: var(--shadow-neu-out);
  position: sticky;
  top: 0;
  z-index: 100;
}

.header-brand-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0.75rem 2rem;
  border-bottom: 1px solid rgba(200,224,244,0.5);
}

.brand-block {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.brand-logo {
  height: 36px;
  width: auto;
  border-radius: var(--radius-sm);
}

.brand-name {
  font-family: var(--font-main);
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--c-dark);
  letter-spacing: -0.02em;
  white-space: nowrap;
}

.header-nav-row {
  padding: 0.5rem 2rem;
  overflow-x: auto;
  scrollbar-width: none;
}

.header-nav-row::-webkit-scrollbar {
  display: none;
}

.pill-nav {
  display: flex;
  gap: 0.5rem;
  align-items: center;
  flex-wrap: nowrap;
}

.pill-nav li {
  flex-shrink: 0;
}

/* ============================================
   胶囊按钮
   ============================================ */
.pill-btn {
  display: inline-flex;
  align-items: center;
  padding: 0.4rem 1rem;
  border-radius: var(--radius-pill);
  font-family: var(--font-body);
  font-size: 0.85rem;
  font-weight: 600;
  background: linear-gradient(145deg, var(--c-blue-light), var(--c-blue));
  box-shadow: var(--shadow-neu-out);
  color: var(--c-dark);
  transition: box-shadow 150ms ease, transform 150ms ease;
  white-space: nowrap;
  min-height: 40px;
}

.pill-btn:hover {
  box-shadow:
    -3px -3px 10px rgba(255,255,255,0.9),
    3px 3px 10px rgba(100,140,180,0.35);
  transform: translateY(-1px);
}

.pill-btn:active,
.pill-btn.active {
  box-shadow: var(--shadow-neu-press);
  transform: scale(0.97);
  background: linear-gradient(145deg, var(--c-blue), var(--c-blue-light));
}

.pill-btn.active {
  color: var(--c-dark);
  font-weight: 700;
}

/* ============================================
   CTA 按钮
   ============================================ */
.cta-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.55rem 1.4rem;
  border-radius: var(--radius-pill);
  font-family: var(--font-main);
  font-size: 0.9rem;
  font-weight: 700;
  background: linear-gradient(145deg, var(--c-dark-mid), var(--c-dark));
  color: var(--c-text-inv);
  box-shadow:
    -3px -3px 8px rgba(255,255,255,0.08),
    3px 3px 12px rgba(0,0,0,0.4);
  transition: box-shadow 150ms ease, transform 150ms ease;
  min-height: 44px;
  white-space: nowrap;
}

.cta-btn:hover {
  box-shadow:
    -4px -4px 12px rgba(255,255,255,0.12),
    4px 4px 16px rgba(0,0,0,0.5);
  transform: translateY(-2px);
}

.cta-btn:active {
  transform: scale(0.96);
  box-shadow:
    inset -2px -2px 6px rgba(255,255,255,0.1),
    inset 2px 2px 8px rgba(0,0,0,0.3);
}

.cta-secondary {
  background: linear-gradient(145deg, var(--c-pink-light), var(--c-pink));
  color: var(--c-dark);
  box-shadow: var(--shadow-neu-out);
}

.cta-secondary:hover {
  box-shadow:
    -4px -4px 12px rgba(255,255,255,0.9),
    4px 4px 12px rgba(200,160,180,0.35);
}

/* ============================================
   Hero（首页 满屏 + 圆弧底）
   ============================================ */
.hero-section {
  position: relative;
  min-height: 100vh;
  background: linear-gradient(160deg, var(--c-dark) 0%, var(--c-dark-mid) 55%, var(--c-dark-light) 100%);
  display: flex;
  flex-direction: column;
  justify-content: center;
  overflow: hidden;
}

.hero-figure {
  flex: 1;
  display: flex;
  align-items: center;
  justify-content: flex-end;
  padding: 8rem 6% 4rem;
  margin: 0;
}

.hero-content {
  max-width: 580px;
  text-align: right;
}

.hero-eyebrow {
  font-family: var(--font-body);
  font-size: 0.8rem;
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--c-blue);
  background: linear-gradient(145deg, var(--c-dark-mid), var(--c-dark-light));
  box-shadow: var(--shadow-dark-out);
  display: inline-block;
  padding: 0.25rem 0.9rem;
  border-radius: var(--radius-pill);
  margin-bottom: 1.2rem;
}

.hero-section h1 {
  font-family: var(--font-main);
  font-size: clamp(2rem, 5vw, 3.5rem);
  font-weight: 700;
  color: var(--c-blue-light);
  line-height: 1.15;
  letter-spacing: -0.03em;
  margin-bottom: 1rem;
}

.hero-lead {
  font-size: 1.05rem;
  color: rgba(200,224,244,0.75);
  line-height: 1.7;
  margin-bottom: 2rem;
}

.hero-actions {
  display: flex;
  gap: 1rem;
  justify-content: flex-end;
  flex-wrap: wrap;
}

.hero-arc {
  position: absolute;
  bottom: -2px;
  left: 0;
  right: 0;
  height: 80px;
  background: var(--c-blue-light);
  clip-path: ellipse(55% 100% at 50% 100%);
}

/* ============================================
   专题 Hero（较小）
   ============================================ */
.topic-hero-section {
  background: linear-gradient(145deg, var(--c-dark) 0%, var(--c-dark-mid) 100%);
  padding-bottom: 3rem;
  position: relative;
  overflow: hidden;
}

.topic-hero-section::after {
  content: '';
  position: absolute;
  bottom: -1px;
  left: 0;
  right: 0;
  height: 50px;
  background: var(--c-blue-light);
  clip-path: ellipse(55% 100% at 50% 100%);
}

.topic-hero-figure {
  margin: 0;
  padding: 5rem 6% 2rem;
}

.topic-hero-content {
  max-width: var(--content-max);
}

.topic-hero-section h1 {
  font-family: var(--font-main);
  font-size: clamp(1.8rem, 4vw, 3rem);
  font-weight: 700;
  color: var(--c-blue-light);
  line-height: 1.2;
  letter-spacing: -0.02em;
  margin-bottom: 0.75rem;
}

.topic-hero-section .hero-lead {
  color: rgba(200,224,244,0.7);
  font-size: 1rem;
}

/* ============================================
   页面标题区（about / privacy）
   ============================================ */
.page-title-section {
  background: linear-gradient(135deg, var(--c-pink) 0%, var(--c-blue) 100%);
  padding-bottom: 3rem;
  position: relative;
  overflow: hidden;
}

.page-title-section::after {
  content: '';
  position: absolute;
  bottom: -1px;
  left: 0;
  right: 0;
  height: 50px;
  background: var(--c-blue-light);
  clip-path: ellipse(55% 100% at 50% 100%);
}

.page-title-figure {
  margin: 0;
  padding: 4.5rem 6% 2rem;
}

.page-title-content {
  max-width: var(--content-max);
}

.page-title-section h1 {
  font-family: var(--font-main);
  font-size: clamp(1.6rem, 3.5vw, 2.6rem);
  font-weight: 700;
  color: var(--c-dark);
  line-height: 1.2;
  letter-spacing: -0.02em;
  margin-bottom: 0.5rem;
}

.privacy-update {
  font-size: 0.85rem;
  color: var(--c-text-muted);
  margin-top: 0.5rem;
}

/* ============================================
   文章 Hero
   ============================================ */
.article-header-section {
  background: linear-gradient(135deg, var(--c-blue) 0%, var(--c-pink) 100%);
  padding-bottom: 3rem;
  position: relative;
  overflow: hidden;
}

.article-header-section::after {
  content: '';
  position: absolute;
  bottom: -1px;
  left: 0;
  right: 0;
  height: 50px;
  background: var(--c-blue-light);
  clip-path: ellipse(55% 100% at 50% 100%);
}

.article-hero-figure {
  margin: 0;
  padding: 4rem 6% 1.5rem;
}

.article-hero-img {
  width: 100%;
  max-height: 360px;
  object-fit: cover;
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-neu-out);
  margin-bottom: 1.5rem;
}

.article-meta {
  display: flex;
  align-items: center;
  gap: 1rem;
  font-size: 0.82rem;
  color: var(--c-text-muted);
  flex-wrap: wrap;
  margin-bottom: 0;
}

.breadcrumb-link {
  background: linear-gradient(145deg, var(--c-blue-light), var(--c-blue));
  box-shadow: var(--shadow-neu-out);
  padding: 0.2rem 0.75rem;
  border-radius: var(--radius-pill);
  font-size: 0.8rem;
  font-weight: 600;
  color: var(--c-dark);
  transition: box-shadow 150ms;
}

.breadcrumb-link:hover {
  box-shadow: var(--shadow-neu-in);
}

.update-tag {
  font-size: 0.8rem;
  color: var(--c-text-muted);
}

.article-title-block {
  padding: 1.5rem 6% 0;
}

.article-title-block h1 {
  font-family: var(--font-main);
  font-size: clamp(1.5rem, 3.5vw, 2.6rem);
  font-weight: 700;
  color: var(--c-dark);
  line-height: 1.25;
  letter-spacing: -0.02em;
  margin-bottom: 0.5rem;
}

.article-lead {
  font-size: 1rem;
  color: var(--c-text-muted);
  line-height: 1.6;
}

/* ============================================
   内容区域布局（aside 左侧 + 正文）
   ============================================ */
.content-section,
.topic-content-section,
.article-body-section,
.about-body-section,
.privacy-body-section {
  padding: 3rem 6%;
  display: flex;
  gap: 2.5rem;
  max-width: calc(var(--page-max) + 12%);
  margin: 0 auto;
  width: 100%;
}

.content-aside {
  flex: 0 0 var(--aside-w);
  min-width: 0;
  order: -1;
}

.content-aside h3 {
  font-family: var(--font-main);
  font-size: 0.85rem;
  font-weight: 700;
  color: var(--c-text-muted);
  letter-spacing: 0.08em;
  text-transform: uppercase;
  margin-bottom: 0.75rem;
  margin-top: 1.25rem;
}

.content-aside h3:first-child {
  margin-top: 0;
}

.aside-links {
  display: flex;
  flex-direction: column;
  gap: 0.3rem;
}

.aside-links li a {
  display: block;
  padding: 0.45rem 0.85rem;
  border-radius: var(--radius-sm);
  background: linear-gradient(145deg, var(--c-blue-light), var(--c-blue));
  box-shadow: var(--shadow-neu-out);
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--c-dark);
  transition: box-shadow 150ms ease, transform 150ms ease;
  min-height: 40px;
  line-height: 1.3;
  display: flex;
  align-items: center;
}

.aside-links li a:hover {
  box-shadow: var(--shadow-neu-in);
  transform: translateX(2px);
}

.aside-divider {
  border: none;
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--c-blue-dark), transparent);
  margin: 1rem 0;
}

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

/* ============================================
   h2 + subtitle 组合
   ============================================ */
.content-main h2,
.topics-section h2,
.articles-section h2,
.children-section h2,
.related-section h2,
.about-topics-section h2 {
  font-family: var(--font-main);
  font-size: clamp(1.3rem, 2.5vw, 2rem);
  font-weight: 700;
  color: var(--c-dark);
  letter-spacing: -0.02em;
  margin-bottom: 0.3rem;
}

.subtitle {
  font-size: 0.95rem;
  color: var(--c-text-muted);
  line-height: 1.6;
  margin-bottom: 1.5rem;
}

/* ============================================
   正文 HTML 内容样式
   ============================================ */
.page-content {
  font-size: 1rem;
  line-height: 1.75;
  color: var(--c-text);
}

.page-content h2 {
  font-family: var(--font-main);
  font-size: 1.4rem;
  font-weight: 700;
  margin: 2rem 0 0.5rem;
  color: var(--c-dark);
}

.page-content h3 {
  font-family: var(--font-main);
  font-size: 1.15rem;
  font-weight: 700;
  margin: 1.5rem 0 0.4rem;
  color: var(--c-dark);
}

.page-content p {
  margin-bottom: 1rem;
}

.page-content ul,
.page-content ol {
  padding-left: 1.5rem;
  margin-bottom: 1rem;
}

.page-content ul {
  list-style: disc;
}

.page-content ol {
  list-style: decimal;
}

.page-content li {
  margin-bottom: 0.35rem;
}

.page-content a {
  color: #3a6fa0;
  text-decoration: underline;
  text-underline-offset: 2px;
}

.page-content a:hover {
  color: var(--c-dark);
}

.page-content strong {
  font-weight: 700;
  color: var(--c-dark);
}

.page-content code {
  background: var(--c-blue);
  padding: 0.15em 0.4em;
  border-radius: 4px;
  font-size: 0.88em;
}

.page-content blockquote {
  border-left: 4px solid var(--c-blue-dark);
  padding: 0.75rem 1rem;
  margin: 1.25rem 0;
  background: linear-gradient(145deg, var(--c-blue-light), var(--c-pink-light));
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  box-shadow: var(--shadow-neu-out);
}

/* ============================================
   Neumorphic 卡片
   ============================================ */
.neo-card {
  background: linear-gradient(145deg, var(--c-blue-light), var(--c-blue));
  border-radius: 18px;
  box-shadow: var(--shadow-card);
  padding: 1.5rem;
  transition: box-shadow 200ms ease, transform 200ms ease;
}

.neo-card:hover {
  box-shadow:
    -8px -8px 20px rgba(255,255,255,0.95),
    8px 8px 20px rgba(140,180,220,0.35);
  transform: translateY(-3px);
}

.neo-card:active {
  box-shadow: var(--shadow-neu-press);
  transform: translateY(0);
}

.neo-card h3 {
  font-family: var(--font-main);
  font-size: 1.05rem;
  font-weight: 700;
  margin-bottom: 0.4rem;
  line-height: 1.3;
}

.neo-card h3 a {
  color: var(--c-dark);
  transition: opacity 150ms;
}

.neo-card h3 a:hover {
  opacity: 0.75;
}

.neo-card .subtitle {
  font-size: 0.88rem;
  color: var(--c-text-muted);
  margin-bottom: 1rem;
}

.article-date {
  display: inline-block;
  font-size: 0.78rem;
  font-weight: 600;
  color: var(--c-text-muted);
  background: linear-gradient(145deg, var(--c-blue), var(--c-blue-dark));
  padding: 0.15rem 0.6rem;
  border-radius: var(--radius-pill);
  margin-bottom: 0.6rem;
  box-shadow: var(--shadow-neu-in);
}

.card-cta,
.read-link {
  display: inline-flex;
  align-items: center;
  padding: 0.35rem 1rem;
  border-radius: var(--radius-pill);
  font-size: 0.82rem;
  font-weight: 700;
  background: linear-gradient(145deg, var(--c-dark-mid), var(--c-dark));
  color: var(--c-text-inv);
  box-shadow: var(--shadow-dark-out);
  transition: opacity 150ms, transform 150ms;
  min-height: 36px;
}

.card-cta:hover,
.read-link:hover {
  opacity: 0.85;
  transform: translateY(-1px);
}

/* ============================================
   专题卡片网格区
   ============================================ */
.topics-section,
.children-section,
.related-section,
.articles-section,
.about-topics-section {
  padding: 2.5rem 6%;
  max-width: calc(var(--page-max) + 12%);
  margin: 0 auto;
  width: 100%;
}

.topics-section,
.children-section,
.related-section,
.articles-section,
.about-topics-section {
  display: grid;
  grid-template-columns: 1fr;
}

.topics-section h2,
.children-section h2,
.related-section h2,
.articles-section h2,
.about-topics-section h2 {
  grid-column: 1 / -1;
}

.topics-section .subtitle,
.children-section .subtitle,
.related-section .subtitle,
.articles-section .subtitle,
.about-topics-section .subtitle {
  grid-column: 1 / -1;
}

/* 卡片区用 grid 布局（section 直接子 article） */
.topics-section,
.children-section,
.related-section,
.articles-section,
.about-topics-section {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 1.25rem;
  align-items: start;
}

.topics-section h2,
.children-section h2,
.related-section h2,
.articles-section h2,
.about-topics-section h2 {
  grid-column: 1 / -1;
  margin-bottom: 0;
}

.topics-section .subtitle,
.children-section .subtitle,
.related-section .subtitle,
.articles-section .subtitle,
.about-topics-section .subtitle {
  grid-column: 1 / -1;
  margin-bottom: 0.5rem;
}

/* ============================================
   粘性动画（stagger）
   ============================================ */
@media (prefers-reduced-motion: no-preference) {
  .neo-card {
    animation: fadeSlideUp 0.4s ease both;
  }

  .topics-section article:nth-child(1) { animation-delay: 0.05s; }
  .topics-section article:nth-child(2) { animation-delay: 0.1s; }
  .topics-section article:nth-child(3) { animation-delay: 0.15s; }
  .topics-section article:nth-child(4) { animation-delay: 0.2s; }
  .articles-section article:nth-child(1) { animation-delay: 0.05s; }
  .articles-section article:nth-child(2) { animation-delay: 0.1s; }
  .articles-section article:nth-child(3) { animation-delay: 0.15s; }
  .articles-section article:nth-child(4) { animation-delay: 0.2s; }
  .articles-section article:nth-child(5) { animation-delay: 0.25s; }
  .articles-section article:nth-child(6) { animation-delay: 0.3s; }
  .children-section article:nth-child(1) { animation-delay: 0.05s; }
  .children-section article:nth-child(2) { animation-delay: 0.1s; }
  .children-section article:nth-child(3) { animation-delay: 0.15s; }
  .related-section article:nth-child(1) { animation-delay: 0.05s; }
  .related-section article:nth-child(2) { animation-delay: 0.1s; }
  .related-section article:nth-child(3) { animation-delay: 0.15s; }
  .related-section article:nth-child(4) { animation-delay: 0.2s; }

  @keyframes fadeSlideUp {
    from { opacity: 0; transform: translateY(18px); }
    to   { opacity: 1; transform: translateY(0); }
  }
}

/* ============================================
   Footer（四栏 Neumorphism）
   ============================================ */
.site-footer {
  background: linear-gradient(160deg, var(--c-dark) 0%, var(--c-dark-mid) 100%);
  color: var(--c-text-inv);
  padding: 4rem 6% 0;
  margin-top: auto;
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  grid-template-rows: auto auto;
  gap: 2rem;
}

.footer-brand-section {
  grid-column: 1 / 2;
  padding: 1.5rem;
  background: linear-gradient(145deg, var(--c-dark-mid), var(--c-dark-light));
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-dark-out);
}

.footer-nav-section,
.footer-links-section,
.footer-info-section {
  padding: 1.5rem;
  background: linear-gradient(145deg, var(--c-dark-mid), var(--c-dark-light));
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-dark-out);
}

.footer-brand-name {
  font-family: var(--font-main);
  font-size: clamp(1.4rem, 2.5vw, 2.4rem);
  font-weight: 700;
  color: var(--c-blue);
  letter-spacing: -0.03em;
  line-height: 1.2;
  margin-bottom: 0.75rem;
}

.footer-desc {
  font-size: 0.82rem;
  color: rgba(200,224,244,0.6);
  line-height: 1.6;
}

.site-footer h4 {
  font-family: var(--font-main);
  font-size: 0.8rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--c-blue);
  margin-bottom: 0.75rem;
}

.site-footer ul {
  display: flex;
  flex-direction: column;
  gap: 0.4rem;
}

.site-footer ul a {
  font-size: 0.85rem;
  color: rgba(224,240,255,0.7);
  transition: color 150ms;
  display: block;
  padding: 0.2rem 0;
  min-height: 32px;
  display: flex;
  align-items: center;
}

.site-footer ul a:hover {
  color: var(--c-blue);
}

.site-footer p {
  font-size: 0.82rem;
  color: rgba(200,224,244,0.6);
  line-height: 1.6;
}

.footer-cta-link {
  display: inline-flex;
  align-items: center;
  margin-top: 0.75rem;
  padding: 0.4rem 1rem;
  border-radius: var(--radius-pill);
  font-size: 0.82rem;
  font-weight: 700;
  background: linear-gradient(145deg, var(--c-blue), var(--c-blue-dark));
  color: var(--c-dark);
  box-shadow: var(--shadow-dark-out);
  transition: opacity 150ms, transform 150ms;
  min-height: 40px;
}

.footer-cta-link:hover {
  opacity: 0.85;
  transform: translateY(-1px);
}

.footer-bottom {
  grid-column: 1 / -1;
  text-align: center;
  padding: 1.25rem 0;
  border-top: 1px solid rgba(200,224,244,0.12);
  font-size: 0.8rem;
  color: rgba(200,224,244,0.4);
}

/* ============================================
   접근성 숨김 텍스트
   ============================================ */
.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  overflow: hidden;
  clip: rect(0 0 0 0);
  white-space: nowrap;
}

/* ============================================
   반응형 — 태블릿 (max 900px)
   ============================================ */
@media (max-width: 900px) {
  .site-footer {
    grid-template-columns: repeat(2, 1fr);
  }

  .footer-brand-section {
    grid-column: 1 / -1;
  }

  .content-section,
  .topic-content-section,
  .article-body-section,
  .about-body-section,
  .privacy-body-section {
    flex-direction: column;
  }

  .content-aside {
    flex: unset;
    width: 100%;
    order: 0;
  }

  .aside-links {
    flex-direction: row;
    flex-wrap: wrap;
  }

  .aside-links li a {
    white-space: nowrap;
  }

  .hero-figure {
    padding: 7rem 5% 3rem;
  }

  .hero-content {
    max-width: 100%;
  }
}

/* ============================================
   모바일 (max 600px)
   ============================================ */
@media (max-width: 600px) {
  :root {
    --aside-w: 100%;
    --gap: 1rem;
  }

  html {
    font-size: 16px;
  }

  .header-brand-row {
    padding: 0.6rem 1rem;
  }

  .header-nav-row {
    padding: 0.4rem 1rem;
  }

  .brand-name {
    font-size: 1rem;
  }

  .hero-figure {
    padding: 6rem 1.25rem 2.5rem;
    justify-content: flex-start;
  }

  .hero-content {
    text-align: left;
    max-width: 100%;
  }

  .hero-actions {
    justify-content: flex-start;
  }

  .topic-hero-figure,
  .page-title-figure,
  .article-hero-figure {
    padding-left: 1.25rem;
    padding-right: 1.25rem;
  }

  .article-title-block {
    padding-left: 1.25rem;
    padding-right: 1.25rem;
  }

  .content-section,
  .topic-content-section,
  .article-body-section,
  .about-body-section,
  .privacy-body-section,
  .topics-section,
  .children-section,
  .related-section,
  .articles-section,
  .about-topics-section {
    padding-left: 1.25rem;
    padding-right: 1.25rem;
  }

  .topics-section,
  .children-section,
  .related-section,
  .articles-section,
  .about-topics-section {
    grid-template-columns: 1fr;
  }

  .site-footer {
    grid-template-columns: 1fr;
    padding: 2rem 1.25rem 0;
    gap: 1rem;
  }

  .footer-brand-section {
    grid-column: 1;
  }

  .footer-brand-name {
    font-size: 1.5rem;
  }

  .pill-btn {
    font-size: 0.78rem;
    padding: 0.35rem 0.75rem;
    min-height: 40px;
  }

  .cta-btn {
    padding: 0.5rem 1.1rem;
    font-size: 0.82rem;
    min-height: 44px;
  }

  .neo-card {
    border-radius: 14px;
    padding: 1.25rem;
  }

  .hero-arc {
    height: 50px;
  }
}

/* ============================================
   prefers-reduced-motion 全局关闭动效
   ============================================ */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation: none !important;
    transition: none !important;
  }
}