/* === 字体引入 === */
@import url('https://fonts.googleapis.com/css2?family=Figtree:wght@300;400;500;600;700&family=Noto+Sans:wght@300;400;500;700&display=swap');

/* === CSS 变量 === */
:root {
  --mint: #b4fde1;
  --sky: #add8e6;
  --ink: #172620;
  --mint-dark: #7de8c0;
  --mint-light: #d6fff1;
  --sky-dark: #7dbfd6;
  --ink-light: #2d4a40;
  --ink-mid: #3d5c50;
  --white: #ffffff;
  --off-white: #f4fdf9;
  --radius-sm: 10px;
  --radius-md: 16px;
  --radius-lg: 24px;
  --border-w: 3px;
  --border-color: var(--ink);
  --shadow-outer: 4px 4px 8px rgba(23,38,32,0.28);
  --shadow-inner: inset -2px -2px 8px rgba(23,38,32,0.10);
  --shadow-clay: var(--shadow-inner), var(--shadow-outer);
  --font-main: 'Figtree', 'Noto Sans', system-ui, -apple-system, sans-serif;
  --text-base: 1rem;
  --lh: 1.65;
  --max-prose: 72ch;
  --max-layout: 1200px;
  --header-h: 64px;
  --transition-press: 200ms cubic-bezier(0.34,1.56,0.64,1);
}

/* === 重置 === */
*, *::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: var(--font-main);
  font-size: var(--text-base);
  line-height: var(--lh);
  color: var(--ink);
  background: var(--off-white);
  min-height: 100vh;
}
img, video { display: block; max-width: 100%; height: auto; }
a { color: inherit; text-decoration: none; }
ul, ol { list-style: none; }
dl, dt, dd { margin: 0; padding: 0; }
button { cursor: pointer; font-family: inherit; }
input { font-family: inherit; }

/* === 通用滚动揭示 === */
.reveal {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 0.5s ease, transform 0.5s ease;
}
.reveal.visible { opacity: 1; transform: none; }
@media (prefers-reduced-motion: reduce) {
  .reveal { opacity: 1; transform: none; transition: none; }
}

/* === 黏土卡片 === */
.clay-card {
  background: linear-gradient(135deg, var(--mint-light) 0%, var(--mint) 60%, var(--sky) 100%);
  border: var(--border-w) solid var(--ink);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-clay);
  transition: transform var(--transition-press), box-shadow var(--transition-press);
}
.clay-card:hover {
  transform: translateY(-3px) scale(1.01);
  box-shadow: inset -2px -2px 8px rgba(23,38,32,0.10), 6px 6px 14px rgba(23,38,32,0.32);
}

/* === 头部导航 === */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: linear-gradient(90deg, var(--mint) 0%, var(--sky) 100%);
  border-bottom: var(--border-w) solid var(--ink);
  box-shadow: 0 3px 10px rgba(23,38,32,0.18);
  height: var(--header-h);
}
.header-inner {
  max-width: var(--max-layout);
  margin: 0 auto;
  padding: 0 1.25rem;
  height: 100%;
  display: flex;
  align-items: center;
  gap: 1rem;
}
.brand-mark {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 44px;
  height: 44px;
  min-width: 44px;
  background: var(--ink);
  border-radius: var(--radius-sm);
  border: var(--border-w) solid var(--ink);
  box-shadow: var(--shadow-outer);
  flex-shrink: 0;
  transition: transform var(--transition-press);
}
.brand-mark:hover { transform: rotate(-5deg) scale(1.08); }
.brand-icon { width: 28px; height: 28px; object-fit: contain; }
.brand-icon-text {
  color: var(--mint);
  font-size: 1.25rem;
  font-weight: 700;
  line-height: 1;
}
.main-nav {
  display: flex;
  align-items: center;
  gap: 0.25rem;
  flex: 1;
  overflow-x: auto;
  scrollbar-width: none;
}
.main-nav::-webkit-scrollbar { display: none; }
.nav-link {
  display: inline-flex;
  align-items: center;
  padding: 0.5rem 0.875rem;
  font-size: 0.875rem;
  font-weight: 600;
  color: var(--ink);
  border-radius: var(--radius-sm);
  border: 2px solid transparent;
  white-space: nowrap;
  min-height: 40px;
  transition: background var(--transition-press), border-color var(--transition-press);
}
.nav-link:hover, .nav-link.active {
  background: var(--ink);
  color: var(--mint);
  border-color: var(--ink);
}
.header-search { display: flex; align-items: center; margin-left: auto; flex-shrink: 0; }
.search-form { display: flex; gap: 0.25rem; }
.search-input {
  padding: 0.4rem 0.75rem;
  border: var(--border-w) solid var(--ink);
  border-radius: var(--radius-sm);
  background: var(--white);
  font-size: 0.875rem;
  width: 140px;
  min-height: 40px;
}
.search-input:focus { outline: 2px solid var(--mint-dark); outline-offset: 2px; }
.search-btn {
  padding: 0.4rem 0.875rem;
  background: var(--ink);
  color: var(--mint);
  border: var(--border-w) solid var(--ink);
  border-radius: var(--radius-sm);
  font-weight: 700;
  font-size: 0.875rem;
  min-height: 40px;
  transition: background var(--transition-press), transform var(--transition-press);
}
.search-btn:hover { background: var(--ink-mid); transform: scale(1.05); }
.nav-toggle {
  display: none;
  background: var(--ink);
  color: var(--mint);
  border: var(--border-w) solid var(--ink);
  border-radius: var(--radius-sm);
  padding: 0.4rem 0.75rem;
  font-size: 1.25rem;
  min-height: 44px;
  min-width: 44px;
}
.mobile-nav {
  display: flex;
  flex-direction: column;
  gap: 0.25rem;
  padding: 0.75rem 1.25rem;
  background: var(--mint);
  border-top: 2px solid var(--ink);
}
.mobile-nav .nav-link { width: 100%; justify-content: flex-start; }
.mobile-nav[hidden] { display: none; }

/* === 锚点条 === */
.anchor-bar {
  background: var(--ink);
  border-bottom: 2px solid var(--ink-light);
}
.sticky-anchor {
  position: sticky;
  top: var(--header-h);
  z-index: 90;
}
.anchor-inner {
  max-width: var(--max-layout);
  margin: 0 auto;
  padding: 0 1.25rem;
  display: flex;
  gap: 0.5rem;
  overflow-x: auto;
  scrollbar-width: none;
}
.anchor-inner::-webkit-scrollbar { display: none; }
.anchor-link {
  display: inline-flex;
  align-items: center;
  padding: 0.6rem 1rem;
  color: var(--mint);
  font-size: 0.8125rem;
  font-weight: 600;
  white-space: nowrap;
  min-height: 40px;
  border-bottom: 2px solid transparent;
  transition: color 150ms, border-color 150ms;
}
.anchor-link:hover { color: var(--sky); border-bottom-color: var(--sky); }

/* === 主内容区 === */
.main-content { max-width: var(--max-layout); margin: 0 auto; padding: 0 1.25rem; }

/* === 页面包裹 === */
.page-wrap { display: flex; flex-direction: column; min-height: 100vh; }
.page-wrap .main-content { flex: 1; }

/* === 首页 Hero === */
.hero-section {
  max-width: var(--max-layout);
  margin: 2rem auto 0;
  padding: 0 1.25rem;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 2rem;
  align-items: center;
  min-height: 45vh;
}
.hero-media {
  position: relative;
  height: 320px;
}
.hero-img-a, .hero-img-b {
  position: absolute;
  border: var(--border-w) solid var(--ink);
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-clay);
}
.hero-img-a {
  width: 62%;
  height: 78%;
  top: 0;
  left: 0;
  z-index: 2;
}
.hero-img-b {
  width: 58%;
  height: 70%;
  bottom: 0;
  right: 0;
  z-index: 1;
  background: var(--sky);
}
.hero-img { width: 100%; height: 100%; object-fit: cover; }
.clay-badge {
  position: absolute;
  background: var(--mint);
  border: var(--border-w) solid var(--ink);
  border-radius: 999px;
  padding: 0.35rem 0.875rem;
  font-size: 0.75rem;
  font-weight: 700;
  color: var(--ink);
  box-shadow: var(--shadow-outer);
  z-index: 5;
  white-space: nowrap;
}
.hero-badge { top: 12px; right: 10px; }
.hero-badge-2 { bottom: 16px; left: 8px; background: var(--sky); }
.hero-copy { padding: 1rem 0; }
.hero-h1 {
  font-size: clamp(1.75rem, 4vw, 2.5rem);
  font-weight: 700;
  line-height: 1.2;
  color: var(--ink);
  margin-bottom: 0.875rem;
}
.hero-desc {
  font-size: 1rem;
  color: var(--ink-mid);
  margin-bottom: 1.5rem;
  max-width: 42ch;
}
.hero-ctas { display: flex; gap: 0.875rem; flex-wrap: wrap; }
.clay-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.65rem 1.5rem;
  border-radius: var(--radius-md);
  border: var(--border-w) solid var(--ink);
  font-weight: 700;
  font-size: 0.9375rem;
  min-height: 44px;
  box-shadow: var(--shadow-outer);
  transition: transform var(--transition-press), box-shadow var(--transition-press);
}
.clay-btn:hover { transform: translateY(-2px) scale(1.03); box-shadow: 5px 5px 12px rgba(23,38,32,0.32); }
.clay-btn:active { transform: translateY(1px) scale(0.98); }
.btn-primary { background: var(--ink); color: var(--mint); }
.btn-secondary { background: var(--mint); color: var(--ink); }

/* === 专题网格 === */
.sections-grid { padding: 2.5rem 0; }
.sections-heading {
  font-size: 1.5rem;
  font-weight: 700;
  margin-bottom: 1.5rem;
  color: var(--ink);
}
.sec-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 1.5rem;
}
.sec-group {
  padding: 1.5rem;
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}
.sec-group-head {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}
.sec-group-title {
  font-size: 1.0625rem;
  font-weight: 700;
  color: var(--ink);
  flex: 1;
}
.sec-group-title:hover { text-decoration: underline; }
.sec-badge {
  background: var(--ink);
  color: var(--mint);
  font-size: 0.6875rem;
  font-weight: 700;
  padding: 0.2rem 0.5rem;
  border-radius: 999px;
}
.sec-group-desc { font-size: 0.875rem; color: var(--ink-mid); }
.child-list { display: flex; flex-direction: column; gap: 0.25rem; }
.child-list dt { font-weight: 600; }
.child-list dd { font-size: 0.8125rem; color: var(--ink-mid); padding-left: 0.5rem; }
.child-link { font-size: 0.9rem; color: var(--ink); }
.child-link:hover { text-decoration: underline; }
.btn-more {
  display: inline-flex;
  align-items: center;
  margin-top: auto;
  font-size: 0.875rem;
  font-weight: 700;
  color: var(--ink);
  padding: 0.4rem 0;
  border-bottom: 2px solid var(--ink);
  align-self: flex-start;
  transition: gap 150ms;
}
.btn-more:hover { gap: 0.5rem; }

/* === 正文内容 === */
.content-section { padding: 2rem 0; }
.prose-wrap {
  max-width: var(--max-prose);
  font-size: 1rem;
  line-height: var(--lh);
  color: var(--ink);
}
.prose-wrap h2 { font-size: 1.375rem; font-weight: 700; margin: 2rem 0 0.75rem; }
.prose-wrap h3 { font-size: 1.125rem; font-weight: 600; margin: 1.5rem 0 0.5rem; }
.prose-wrap p { margin-bottom: 1rem; }
.prose-wrap ul, .prose-wrap ol { padding-left: 1.5rem; margin-bottom: 1rem; }
.prose-wrap li { margin-bottom: 0.375rem; }
.prose-wrap ul { list-style: disc; }
.prose-wrap ol { list-style: decimal; }
.prose-wrap a { color: var(--ink-mid); text-decoration: underline; font-weight: 600; }
.prose-wrap a:hover { color: var(--ink); }
.prose-wrap blockquote {
  border-left: 4px solid var(--mint-dark);
  background: var(--mint-light);
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  padding: 0.875rem 1.25rem;
  margin: 1.25rem 0;
  font-style: italic;
}
.prose-wrap table { width: 100%; border-collapse: collapse; margin: 1.25rem 0; font-size: 0.9375rem; }
.prose-wrap th, .prose-wrap td {
  border: 2px solid var(--ink);
  padding: 0.6rem 0.875rem;
  text-align: left;
}
.prose-wrap th { background: var(--mint); font-weight: 700; }
.prose-wrap tr:nth-child(even) td { background: var(--mint-light); }
.prose-wrap img {
  border-radius: var(--radius-md);
  border: var(--border-w) solid var(--ink);
  box-shadow: var(--shadow-outer);
  margin: 1rem 0;
}
.prose-wrap time {
  font-weight: 600;
  background: var(--sky);
  padding: 0.1rem 0.5rem;
  border-radius: 4px;
}

/* === 栏目页 Hero === */
.clay-section-hero {
  max-width: var(--max-layout);
  margin: 1.5rem auto 0;
  padding: 2rem 1.25rem;
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 2rem;
  align-items: center;
  background: linear-gradient(120deg, var(--mint-light) 0%, var(--sky) 100%);
  border: var(--border-w) solid var(--ink);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-clay);
}
.section-hero-inner { min-width: 0; }
.section-h1 { font-size: clamp(1.5rem, 3.5vw, 2.25rem); font-weight: 700; margin: 0.5rem 0; }
.section-hero-desc { color: var(--ink-mid); font-size: 1rem; max-width: 52ch; }
.section-hero-img { width: 200px; flex-shrink: 0; }
.section-cover { width: 100%; height: 140px; object-fit: cover; border-radius: var(--radius-md); border: var(--border-w) solid var(--ink); }

/* === 子页列表 === */
.children-section { padding: 2rem 0; }
.children-heading { font-size: 1.375rem; font-weight: 700; margin-bottom: 1.25rem; }
.children-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
  gap: 1.25rem;
}
.child-card {
  display: flex;
  flex-direction: column;
  position: relative;
  overflow: hidden;
}
.card-thumb-wrap { overflow: hidden; border-radius: var(--radius-sm) var(--radius-sm) 0 0; }
.card-thumb { width: 100%; height: 160px; object-fit: cover; display: block; transition: transform 300ms ease; }
.child-card:hover .card-thumb { transform: scale(1.04); }
.card-body { padding: 1rem 1rem 0.75rem; flex: 1; display: flex; flex-direction: column; gap: 0.375rem; }
.card-title-link { font-size: 1rem; font-weight: 700; color: var(--ink); display: block; }
.card-title-link:hover { text-decoration: underline; }
.card-desc { font-size: 0.875rem; color: var(--ink-mid); flex: 1; }
.card-date { font-size: 0.75rem; color: var(--ink-mid); display: block; }
.card-accent-line {
  height: 4px;
  background: linear-gradient(90deg, var(--ink) 0%, var(--mint-dark) 100%);
  border-radius: 0 0 var(--radius-sm) var(--radius-sm);
  margin-top: auto;
}

/* === 文章页 === */
.story-article { padding: 1.5rem 0 2rem; }
.story-header { margin-bottom: 1.5rem; }
.story-hero-img {
  margin: 1rem 0;
  border-radius: var(--radius-lg);
  overflow: hidden;
  border: var(--border-w) solid var(--ink);
  box-shadow: var(--shadow-clay);
}
.story-cover { width: 100%; max-height: 360px; object-fit: cover; }
.story-title-block {
  padding: 1.5rem;
  margin-top: 1rem;
  background: linear-gradient(135deg, var(--white) 0%, var(--mint-light) 100%);
}
.story-h1 { font-size: clamp(1.5rem, 3.5vw, 2.25rem); font-weight: 700; margin-bottom: 0.75rem; }
.story-desc { font-size: 1rem; color: var(--ink-mid); margin-top: 0.5rem; }
.story-meta-dates {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  flex-wrap: wrap;
  font-size: 0.875rem;
}
.meta-label { font-weight: 600; color: var(--ink-mid); }
.meta-date { font-weight: 500; }
.meta-sep { color: var(--ink-mid); }
.story-body-layout {
  display: grid;
  grid-template-columns: 1fr 280px;
  gap: 2rem;
  align-items: start;
}
.story-main-col { min-width: 0; }
.story-side-col { position: sticky; top: calc(var(--header-h) + 48px); display: flex; flex-direction: column; gap: 1.25rem; }
.related-aside { padding: 1.25rem; }
.related-heading { font-size: 1rem; font-weight: 700; margin-bottom: 0.875rem; }
.related-list { display: flex; flex-direction: column; gap: 0.625rem; }
.related-list dt { font-weight: 600; font-size: 0.9rem; }
.related-list dd { font-size: 0.8125rem; color: var(--ink-mid); padding-left: 0.5rem; }
.related-link:hover { text-decoration: underline; }
.sidebar-nav { padding: 1.25rem; }
.sidebar-nav-title { font-size: 0.9375rem; font-weight: 700; margin-bottom: 0.75rem; }
.sidebar-parent-link { font-size: 0.875rem; font-weight: 600; color: var(--ink); display: block; margin-bottom: 0.625rem; }
.sidebar-parent-link:hover { text-decoration: underline; }
.sidebar-kids-list { display: flex; flex-direction: column; gap: 0.375rem; }
.sidebar-kids-list dt a {
  font-size: 0.875rem;
  color: var(--ink-mid);
  display: block;
  padding: 0.25rem 0;
  border-bottom: 1px solid rgba(23,38,32,0.08);
}
.sidebar-kids-list dt a:hover, .sidebar-kids-list dt a.active-link { color: var(--ink); font-weight: 600; }

/* === 关于页 === */
.about-article { padding: 1.5rem 0 2rem; }
.clay-about-hero {
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 2rem;
  align-items: center;
  background: linear-gradient(120deg, var(--mint) 0%, var(--sky) 100%);
  border: var(--border-w) solid var(--ink);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-clay);
  padding: 2rem 1.5rem;
  margin-bottom: 1.5rem;
}
.about-h1 { font-size: clamp(1.5rem, 3.5vw, 2.25rem); font-weight: 700; margin: 0.5rem 0; }
.about-intro { color: var(--ink-mid); max-width: 52ch; }
.about-logo { border-radius: var(--radius-md); border: var(--border-w) solid var(--ink); box-shadow: var(--shadow-outer); }
.about-logo-fallback {
  background: var(--ink);
  color: var(--mint);
  font-size: 1.5rem;
  font-weight: 700;
  padding: 1rem 1.5rem;
  border-radius: var(--radius-md);
  border: var(--border-w) solid var(--ink);
}
.about-content { border-top: 2px solid rgba(23,38,32,0.12); }
.about-links-section { padding: 2rem 0; }
.about-links-heading { font-size: 1.25rem; font-weight: 700; margin-bottom: 1.25rem; }
.about-links-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(220px, 1fr)); gap: 1rem; }
.about-nav-card {
  display: flex;
  flex-direction: column;
  gap: 0.375rem;
  padding: 1.25rem;
  transition: transform var(--transition-press), box-shadow var(--transition-press);
}
.about-nav-title { font-size: 0.9375rem; font-weight: 700; color: var(--ink); }
.about-nav-desc { font-size: 0.8125rem; color: var(--ink-mid); }

/* === 隐私页 === */
.privacy-article { padding: 1.5rem 0 2rem; }
.privacy-header {
  padding: 1.5rem;
  margin-bottom: 1.5rem;
  background: linear-gradient(120deg, var(--white) 0%, var(--sky) 100%);
}
.privacy-h1 { font-size: clamp(1.375rem, 3vw, 2rem); font-weight: 700; margin: 0.5rem 0; }
.privacy-desc { color: var(--ink-mid); margin-top: 0.5rem; }
.privacy-dates {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  flex-wrap: wrap;
  font-size: 0.875rem;
  margin-top: 0.5rem;
}
.privacy-footer-links {
  padding: 1.25rem 1.5rem;
  margin-top: 1.5rem;
  font-size: 0.9375rem;
}
.privacy-footer-links a { font-weight: 600; text-decoration: underline; color: var(--ink-mid); }
.privacy-footer-links a:hover { color: var(--ink); }

/* === 面包屑 === */
.breadcrumb {
  font-size: 0.8125rem;
  color: var(--ink-mid);
  display: flex;
  align-items: center;
  gap: 0.25rem;
  flex-wrap: wrap;
  margin-bottom: 0.75rem;
}
.breadcrumb a { font-weight: 600; color: var(--ink); }
.breadcrumb a:hover { text-decoration: underline; }

/* === 页脚 === */
.site-footer {
  background: var(--ink);
  color: var(--mint);
  margin-top: 4rem;
  border-top: var(--border-w) solid var(--ink-light);
}
.footer-top {
  max-width: var(--max-layout);
  margin: 0 auto;
  padding: 3rem 1.25rem 1.5rem;
  border-bottom: 1px solid rgba(180,253,225,0.15);
}
.footer-brand-big {
  display: block;
  font-size: clamp(2.5rem, 8vw, 5rem);
  font-weight: 700;
  line-height: 1;
  letter-spacing: -0.02em;
  color: var(--mint);
  margin-bottom: 0.5rem;
}
.footer-tagline { font-size: 0.9375rem; color: rgba(180,253,225,0.72); max-width: 60ch; }
.footer-cols {
  max-width: var(--max-layout);
  margin: 0 auto;
  padding: 2rem 1.25rem;
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 2rem;
  border-bottom: 1px solid rgba(180,253,225,0.12);
}
.footer-col-title {
  font-size: 0.75rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--mint-dark);
  margin-bottom: 0.875rem;
}
.footer-nav-dl { display: flex; flex-direction: column; gap: 0.375rem; }
.footer-nav-dl dt { display: none; }
.footer-nav-dl dd { }
.footer-nav-dl a {
  display: inline-flex;
  align-items: center;
  font-size: 0.875rem;
  color: rgba(180,253,225,0.75);
  min-height: 32px;
  transition: color 150ms;
}
.footer-nav-dl a:hover { color: var(--mint); text-decoration: underline; }
.footer-bottom {
  max-width: var(--max-layout);
  margin: 0 auto;
  padding: 1.25rem 1.25rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 1rem;
  flex-wrap: wrap;
}
.footer-copy { font-size: 0.8125rem; color: rgba(180,253,225,0.55); }
.footer-links { display: flex; gap: 1rem; }
.footer-links a {
  font-size: 0.8125rem;
  color: rgba(180,253,225,0.7);
  min-height: 40px;
  display: inline-flex;
  align-items: center;
}
.footer-links a:hover { color: var(--mint); text-decoration: underline; }

/* === 首页文章布局 === */
.home-article { padding: 1.5rem 0; }

/* === 栏目文章布局 === */
.section-article { padding: 1.5rem 0 2rem; }

/* === 响应式 === */
@media (max-width: 960px) {
  .story-body-layout { grid-template-columns: 1fr; }
  .story-side-col { position: static; }
  .footer-cols { grid-template-columns: repeat(2, 1fr); }
  .hero-section { grid-template-columns: 1fr; min-height: auto; }
  .hero-media { height: 240px; }
  .clay-section-hero { grid-template-columns: 1fr; }
  .section-hero-img { display: none; }
  .clay-about-hero { grid-template-columns: 1fr; }
  .about-logo-block { display: none; }
}

@media (max-width: 680px) {
  :root { --header-h: 56px; }
  .main-nav { display: none; }
  .header-search { display: none; }
  .nav-toggle { display: flex; align-items: center; justify-content: center; margin-left: auto; }
  .footer-cols { grid-template-columns: 1fr 1fr; gap: 1.25rem; }
  .hero-section { margin-top: 1rem; gap: 1.25rem; }
  .hero-media { height: 200px; }
  .hero-h1 { font-size: 1.5rem; }
  .sec-grid { grid-template-columns: 1fr; }
  .children-grid { grid-template-columns: 1fr; }
  .about-links-grid { grid-template-columns: 1fr; }
  .clay-section-hero { padding: 1.25rem; }
  .story-title-block { padding: 1rem; }
  .anchor-bar .anchor-inner { padding: 0 0.75rem; }
  .sections-grid { padding: 1.5rem 0; }
}

@media (max-width: 400px) {
  .footer-cols { grid-template-columns: 1fr; }
  .footer-brand-big { font-size: 2.5rem; }
  .hero-ctas { flex-direction: column; }
  .clay-btn { width: 100%; justify-content: center; }
}

/* === 工具 === */
.sr-only {
  position: absolute;
  width: 1px; height: 1px;
  padding: 0; margin: -1px;
  overflow: hidden;
  clip: rect(0,0,0,0);
  white-space: nowrap;
  border: 0;
}