@import url('https://fonts.googleapis.com/css2?family=Lora:wght@400;500;600;700&family=Raleway:wght@300;400;500;600;700&display=swap');

/* ===== 变量 ===== */
:root {
  --c-primary: #6514ff;
  --c-accent: #bf00ff;
  --c-dark: #1c1726;
  --c-primary-light: #8b4dff;
  --c-accent-light: #d966ff;
  --c-bg: #0e0b18;
  --c-bg2: #160e2a;
  --c-bg3: #1f1440;
  --c-surface: #231850;
  --c-surface2: #2e1f6e;
  --c-text: #f0e8ff;
  --c-text-muted: #b8a8d9;
  --c-text-dim: #7a6ba0;
  --c-border: #3d2b80;
  --ff-heading: 'Raleway', 'PingFang SC', 'Microsoft YaHei', sans-serif;
  --ff-body: 'Lora', 'PingFang SC', 'Microsoft YaHei', serif;
  --radius: 0;
  --nav-h: 56px;
  --gap-sm: 16px;
  --gap-md: 32px;
  --gap-lg: 48px;
  --gap-xl: 64px;
  --max-w: 1200px;
  --prose-w: 720px;
  --transition: 200ms cubic-bezier(0.4, 0, 0.2, 1);
}

/* ===== 重置 ===== */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; font-size: 18px; }
body {
  background: var(--c-bg);
  color: var(--c-text);
  font-family: var(--ff-body);
  font-size: 1rem;
  line-height: 1.75;
  min-height: 100vh;
  padding-bottom: calc(var(--nav-h) + 16px);
  position: relative;
  overflow-x: hidden;
}
img { max-width: 100%; height: auto; display: block; }
a { color: var(--c-primary-light); text-decoration: none; transition: color var(--transition); }
a:hover, a:focus-visible { color: var(--c-accent-light); }
button { cursor: pointer; font-family: inherit; }
ol, ul { list-style: none; }
input { font-family: inherit; }

/* ===== 动态背景纹理 ===== */
body::before {
  content: '';
  position: fixed;
  inset: 0;
  background:
    radial-gradient(ellipse 80% 60% at 20% 20%, rgba(101,20,255,0.18) 0%, transparent 60%),
    radial-gradient(ellipse 60% 80% at 80% 80%, rgba(191,0,255,0.12) 0%, transparent 60%),
    repeating-linear-gradient(
      0deg,
      transparent,
      transparent 48px,
      rgba(101,20,255,0.04) 48px,
      rgba(101,20,255,0.04) 49px
    ),
    repeating-linear-gradient(
      90deg,
      transparent,
      transparent 48px,
      rgba(101,20,255,0.04) 48px,
      rgba(101,20,255,0.04) 49px
    );
  pointer-events: none;
  z-index: 0;
  animation: bgShift 20s ease-in-out infinite alternate;
}
@keyframes bgShift {
  0% { transform: translate(0, 0); }
  100% { transform: translate(8px, -8px); }
}
@media (prefers-reduced-motion: reduce) {
  body::before { animation: none; }
}

/* ===== 底部固定导航栏 ===== */
.nav-bottom-bar {
  position: fixed;
  bottom: 0;
  left: 0;
  right: 0;
  z-index: 100;
  background: rgba(14, 11, 24, 0.97);
  border-top: 2px solid var(--c-primary);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
}
.nav-inner {
  display: flex;
  align-items: center;
  gap: var(--gap-sm);
  padding: 0 var(--gap-md);
  height: var(--nav-h);
  max-width: var(--max-w);
  margin: 0 auto;
}
.nav-brand {
  font-family: var(--ff-heading);
  font-weight: 700;
  font-size: 1rem;
  color: var(--c-text);
  white-space: nowrap;
  flex-shrink: 0;
  min-height: 40px;
  display: flex;
  align-items: center;
  padding: 0 8px;
  letter-spacing: 0.02em;
}
.nav-brand:hover { color: var(--c-accent-light); }
.nav-search {
  flex: 1;
  max-width: 240px;
}
.nav-search input {
  width: 100%;
  background: var(--c-surface);
  border: 1px solid var(--c-border);
  color: var(--c-text);
  padding: 6px 12px;
  font-size: 0.875rem;
  outline: none;
  border-radius: 0;
  transition: border-color var(--transition);
}
.nav-search input:focus { border-color: var(--c-primary); }
.nav-search input::placeholder { color: var(--c-text-dim); }
.nav-toggle {
  margin-left: auto;
  background: var(--c-primary);
  color: #fff;
  border: none;
  width: 40px;
  height: 40px;
  font-size: 1.1rem;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  transition: background var(--transition);
}
.nav-toggle:hover { background: var(--c-accent); }
.main-nav {
  display: none;
  background: rgba(14,11,24,0.98);
  border-top: 1px solid var(--c-border);
  padding: var(--gap-sm) var(--gap-md);
  max-width: var(--max-w);
  margin: 0 auto;
}
.main-nav.is-open { display: block; }
.main-nav ol {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 16px;
  list-style: none;
}
.main-nav ol li a {
  font-family: var(--ff-heading);
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--c-text-muted);
  padding: 8px 12px;
  min-height: 40px;
  display: inline-flex;
  align-items: center;
  border: 1px solid transparent;
  transition: all var(--transition);
  letter-spacing: 0.03em;
}
.main-nav ol li a:hover,
.main-nav ol li a[aria-current="page"] {
  color: var(--c-text);
  border-color: var(--c-primary);
  background: rgba(101,20,255,0.15);
}

/* ===== 页脚 ===== */
.site-footer {
  position: relative;
  z-index: 1;
  background: var(--c-dark);
  border-top: 2px solid var(--c-surface);
  padding: var(--gap-md) var(--gap-md) calc(var(--gap-md) + var(--nav-h));
  max-width: 100%;
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: var(--gap-sm);
}
.footer-brand {
  font-family: var(--ff-heading);
  font-size: 0.875rem;
  color: var(--c-text-muted);
  font-weight: 500;
}
.site-footer small {
  font-size: 0.8rem;
  color: var(--c-text-dim);
}
.site-footer small a {
  color: var(--c-text-dim);
  min-height: 40px;
  display: inline-flex;
  align-items: center;
  padding: 2px 4px;
}
.site-footer small a:hover { color: var(--c-accent-light); }

/* ===== 侧边栏通用 ===== */
.home-aside,
.topic-aside,
.article-aside,
.about-aside,
.privacy-aside {
  width: 240px;
  flex-shrink: 0;
}
.aside-nav-list { list-style: none; }
.aside-nav-list li { border-bottom: 1px solid var(--c-border); }
.aside-nav-list li a {
  display: block;
  padding: 10px 12px;
  font-family: var(--ff-heading);
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--c-text-muted);
  transition: all var(--transition);
  min-height: 40px;
  line-height: 1.4;
}
.aside-nav-list li a:hover { color: var(--c-text); background: rgba(101,20,255,0.15); padding-left: 18px; }
.aside-divider { height: 1px; background: var(--c-border); margin: var(--gap-sm) 0; }
.aside-note {
  font-size: 0.8rem;
  color: var(--c-text-dim);
  line-height: 1.6;
  padding: 8px 0;
}
.aside-block { margin-bottom: var(--gap-md); }
.aside-topic-list { margin-top: 8px; }

/* ===== h2/h3 装饰 ===== */
h2, h3 {
  font-family: var(--ff-heading);
  font-weight: 700;
  letter-spacing: 0.02em;
}
h2 > span:first-child {
  display: inline-block;
  position: relative;
}
h2 > span:first-child::after {
  content: '';
  display: block;
  height: 3px;
  background: linear-gradient(90deg, var(--c-primary), var(--c-accent));
  margin-top: 4px;
  width: 100%;
}
h3 > span:first-child {
  display: inline-block;
  border-left: 3px solid var(--c-accent);
  padding-left: 8px;
}
.section-sub {
  font-size: 0.75em;
  font-weight: 400;
  color: var(--c-text-dim);
  margin-left: 12px;
  font-family: var(--ff-body);
  letter-spacing: 0;
}

/* ===== 首页 ===== */
.home-main {
  position: relative;
  z-index: 1;
  min-height: calc(100vh - var(--nav-h));
}
.home-main > div > section {
  padding: var(--gap-lg) var(--gap-md);
  max-width: var(--max-w);
  margin: 0 auto;
}

/* Hero */
.hero-section {
  position: relative;
  min-height: 45vh;
  display: flex;
  align-items: center;
  overflow: hidden;
  padding: var(--gap-xl) var(--gap-md) !important;
}
.hero-bg-text {
  position: absolute;
  top: 50%;
  right: -2%;
  transform: translateY(-50%);
  font-family: var(--ff-heading);
  font-weight: 700;
  font-size: clamp(6rem, 20vw, 16rem);
  color: rgba(101,20,255,0.08);
  letter-spacing: -0.04em;
  user-select: none;
  pointer-events: none;
  white-space: nowrap;
}
.hero-content {
  position: relative;
  z-index: 2;
  max-width: 680px;
}
.hero-eyebrow {
  font-family: var(--ff-heading);
  font-size: 0.875rem;
  font-weight: 600;
  letter-spacing: 0.12em;
  color: var(--c-accent-light);
  text-transform: uppercase;
  margin-bottom: 16px;
  display: inline-block;
  border: 1px solid var(--c-accent);
  padding: 4px 12px;
}
.hero-content h1 {
  font-size: clamp(2rem, 5vw, 3.5rem);
  line-height: 1.2;
  color: #fff;
  margin-bottom: var(--gap-sm);
  font-weight: 700;
}
.hero-sub {
  font-size: 1.05rem;
  color: var(--c-text-muted);
  margin-bottom: var(--gap-md);
  line-height: 1.7;
  max-width: 540px;
}
.hero-cta {
  display: inline-flex;
  align-items: center;
  background: var(--c-primary);
  color: #fff;
  padding: 12px 28px;
  font-family: var(--ff-heading);
  font-weight: 700;
  font-size: 1rem;
  min-height: 48px;
  transition: background var(--transition), transform var(--transition);
  letter-spacing: 0.04em;
}
.hero-cta:hover { background: var(--c-accent); color: #fff; transform: translateY(-2px); }

/* 首页 content section */
.content-section {
  display: flex;
  gap: var(--gap-xl);
  align-items: flex-start;
}
.home-prose {
  flex: 1;
  min-width: 0;
  font-size: 1rem;
  line-height: 1.8;
  color: var(--c-text-muted);
}

/* 分类卡片 */
.topics-section {
  border-top: 1px solid var(--c-border);
}
.topics-section h2 {
  font-size: 1.75rem;
  margin-bottom: var(--gap-lg);
  color: #fff;
}
.topics-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
  gap: var(--gap-md);
}
.topic-card {
  background: var(--c-surface);
  padding: var(--gap-md);
  border-left: 4px solid var(--c-primary);
  display: flex;
  flex-direction: column;
  gap: 10px;
  transition: background var(--transition), border-color var(--transition), transform var(--transition);
  position: relative;
  overflow: hidden;
}
.topic-card::before {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, rgba(101,20,255,0.1), transparent);
  opacity: 0;
  transition: opacity var(--transition);
}
.topic-card:hover { background: var(--c-surface2); border-color: var(--c-accent); transform: translateY(-4px); }
.topic-card:hover::before { opacity: 1; }
.topic-num {
  font-family: var(--ff-heading);
  font-size: 2rem;
  font-weight: 700;
  color: var(--c-primary);
  line-height: 1;
}
.topic-card h3 {
  font-size: 1rem;
  color: #fff;
  line-height: 1.4;
}
.topic-desc {
  font-size: 0.825rem;
  color: var(--c-text-muted);
  line-height: 1.6;
  flex: 1;
}
.topic-count {
  font-size: 0.75rem;
  font-family: var(--ff-heading);
  color: var(--c-accent-light);
  font-weight: 600;
}
.topic-link {
  font-family: var(--ff-heading);
  font-size: 0.875rem;
  font-weight: 700;
  color: var(--c-primary-light);
  padding: 8px 0;
  min-height: 40px;
  display: inline-flex;
  align-items: center;
}
.topic-link:hover { color: var(--c-accent-light); }

/* 最新收录 */
.recent-section {
  border-top: 1px solid var(--c-border);
}
.recent-section h2 {
  font-size: 1.75rem;
  margin-bottom: var(--gap-lg);
  color: #fff;
}
.recent-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
  gap: var(--gap-md);
}
.recent-card {
  background: var(--c-bg2);
  border: 1px solid var(--c-border);
  padding: var(--gap-md);
  display: flex;
  flex-direction: column;
  gap: 10px;
  transition: border-color var(--transition), background var(--transition);
}
.recent-card:hover { border-color: var(--c-primary); background: var(--c-surface); }
.cat-badge {
  font-family: var(--ff-heading);
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.06em;
  background: rgba(101,20,255,0.3);
  color: var(--c-primary-light);
  padding: 2px 8px;
  display: inline-block;
  align-self: flex-start;
}
.recent-card h3 {
  font-size: 0.975rem;
  line-height: 1.4;
}
.recent-card h3 a { color: #fff; }
.recent-card h3 a:hover { color: var(--c-accent-light); }
.recent-card p {
  font-size: 0.85rem;
  color: var(--c-text-muted);
  flex: 1;
}
.recent-card time {
  font-size: 0.75rem;
  color: var(--c-text-dim);
  font-family: var(--ff-heading);
}

/* ===== 栏目页 ===== */
.topic-main {
  position: relative;
  z-index: 1;
}
.topic-main > div > section {
  padding: var(--gap-lg) var(--gap-md);
  max-width: var(--max-w);
  margin: 0 auto;
}
.topic-hero {
  position: relative;
  min-height: 40vh;
  display: flex !important;
  flex-direction: column;
  justify-content: flex-end;
  overflow: hidden;
  background: linear-gradient(135deg, var(--c-bg2), var(--c-bg));
  border-bottom: 2px solid var(--c-primary);
}
.topic-hero-bg {
  position: absolute;
  top: 50%;
  right: 4%;
  transform: translateY(-50%);
  font-family: var(--ff-heading);
  font-weight: 700;
  font-size: clamp(4rem, 16vw, 12rem);
  color: rgba(101,20,255,0.1);
  letter-spacing: -0.05em;
  user-select: none;
  pointer-events: none;
  line-height: 1;
}
.topic-hero-content {
  position: relative;
  z-index: 2;
  padding: var(--gap-xl) var(--gap-md) var(--gap-lg);
  max-width: var(--max-w);
  margin: 0 auto;
  width: 100%;
}
.breadcrumb-back {
  font-family: var(--ff-heading);
  font-size: 0.875rem;
  color: var(--c-text-dim);
  display: inline-flex;
  align-items: center;
  min-height: 40px;
  margin-bottom: var(--gap-sm);
  padding: 4px 0;
}
.breadcrumb-back:hover { color: var(--c-primary-light); }
.topic-hero-content h1 {
  font-size: clamp(1.75rem, 4vw, 3rem);
  color: #fff;
  margin-bottom: var(--gap-sm);
  line-height: 1.2;
}
.topic-desc {
  font-size: 1rem;
  color: var(--c-text-muted);
  max-width: 560px;
  margin-bottom: var(--gap-sm);
}
.topic-count-badge {
  font-family: var(--ff-heading);
  font-size: 0.875rem;
  font-weight: 700;
  background: var(--c-primary);
  color: #fff;
  padding: 4px 14px;
  display: inline-block;
}
.topic-body-section {
  display: flex;
  gap: var(--gap-xl);
  align-items: flex-start;
}
.topic-aside h2, .topic-aside h3 {
  font-size: 1rem;
  margin-bottom: 8px;
  color: var(--c-text);
}
.topic-content-area {
  flex: 1;
  min-width: 0;
}
.topic-prose {
  font-size: 1rem;
  line-height: 1.8;
  color: var(--c-text-muted);
  margin-bottom: var(--gap-xl);
}
.child-list-block h2 {
  font-size: 1.5rem;
  color: #fff;
  margin-bottom: var(--gap-md);
}
.child-dl { list-style: none; }
.child-dt {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  gap: 16px;
  padding: 14px 16px;
  background: var(--c-surface);
  border-left: 3px solid var(--c-primary);
  margin-bottom: 2px;
  flex-wrap: wrap;
  transition: background var(--transition), border-color var(--transition);
}
.child-dt:hover { background: var(--c-surface2); border-color: var(--c-accent); }
.child-dt a {
  font-family: var(--ff-heading);
  font-weight: 600;
  font-size: 1rem;
  color: #fff;
}
.child-dt a:hover { color: var(--c-accent-light); }
.child-meta {
  font-size: 0.75rem;
  color: var(--c-text-dim);
  font-family: var(--ff-heading);
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
}
.child-dd {
  padding: 10px 16px 16px 20px;
  font-size: 0.875rem;
  color: var(--c-text-muted);
  line-height: 1.6;
  margin-bottom: 8px;
  border-left: 3px solid var(--c-border);
}

/* ===== 文章页 ===== */
.article-main {
  position: relative;
  z-index: 1;
}
.article-main > div > section {
  padding: var(--gap-lg) var(--gap-md);
  max-width: var(--max-w);
  margin: 0 auto;
}
.article-breadcrumb {
  font-size: 0.8rem;
  color: var(--c-text-dim);
  margin-bottom: var(--gap-md);
  font-family: var(--ff-heading);
  display: flex;
  flex-wrap: wrap;
  gap: 4px;
  align-items: center;
}
.article-breadcrumb a { color: var(--c-text-dim); min-height: 40px; display: inline-flex; align-items: center; }
.article-breadcrumb a:hover { color: var(--c-primary-light); }
.article-header-section h1 {
  font-size: clamp(1.75rem, 4vw, 2.75rem);
  color: #fff;
  line-height: 1.2;
  margin-bottom: var(--gap-sm);
}
.article-desc {
  font-size: 1.05rem;
  color: var(--c-text-muted);
  max-width: 640px;
  margin-bottom: var(--gap-sm);
}
.article-meta {
  display: flex;
  gap: 24px;
  flex-wrap: wrap;
  margin-bottom: var(--gap-md);
}
.article-date, .article-date-mod {
  font-family: var(--ff-heading);
  font-size: 0.8rem;
  color: var(--c-text-dim);
  display: inline-flex;
  align-items: center;
  gap: 6px;
}
.article-hero-wrap { margin: var(--gap-md) 0; }
.article-hero-img { width: 100%; max-height: 480px; object-fit: cover; }
.article-content-section {
  display: flex;
  gap: var(--gap-xl);
  align-items: flex-start;
}
.article-aside { order: -1; }
.article-aside h2, .article-aside h3 {
  font-size: 1rem;
  margin-bottom: 8px;
  color: var(--c-text);
}
.article-prose {
  flex: 1;
  min-width: 0;
  font-size: 1rem;
  line-height: 1.85;
  color: var(--c-text-muted);
  max-width: var(--prose-w);
}
.article-prose h2 {
  font-size: 1.4rem;
  color: #fff;
  margin: 2em 0 0.75em;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--c-border);
}
.article-prose h3 {
  font-size: 1.15rem;
  color: var(--c-primary-light);
  margin: 1.5em 0 0.5em;
}
.article-prose p { margin-bottom: 1.2em; }
.article-prose ul, .article-prose ol {
  padding-left: 1.5em;
  margin-bottom: 1.2em;
  list-style: disc;
}
.article-prose ol { list-style: decimal; }
.article-prose li { margin-bottom: 0.5em; }
.article-prose strong { color: #fff; font-weight: 600; }
.article-prose em { color: var(--c-accent-light); font-style: italic; }
.article-prose blockquote {
  border-left: 4px solid var(--c-primary);
  padding: 12px 20px;
  background: var(--c-surface);
  color: var(--c-text-muted);
  margin: 1.5em 0;
  font-style: italic;
}
.article-prose a { text-decoration: underline; text-decoration-color: var(--c-primary); }
.article-prose a:hover { color: var(--c-accent-light); }
.article-footer-section {
  border-top: 1px solid var(--c-border);
}
.article-tags-row {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
}
.tag-link {
  font-family: var(--ff-heading);
  font-size: 0.8rem;
  font-weight: 600;
  background: rgba(101,20,255,0.2);
  border: 1px solid var(--c-primary);
  color: var(--c-primary-light);
  padding: 6px 14px;
  min-height: 36px;
  display: inline-flex;
  align-items: center;
  transition: all var(--transition);
}
.tag-link:hover { background: var(--c-primary); color: #fff; }

/* ===== 关于页 ===== */
.about-main {
  position: relative;
  z-index: 1;
}
.about-main > div > section {
  padding: var(--gap-lg) var(--gap-md);
  max-width: var(--max-w);
  margin: 0 auto;
}
.about-hero {
  position: relative;
  padding: var(--gap-xl) var(--gap-md) var(--gap-lg) !important;
  border-bottom: 2px solid var(--c-primary);
  overflow: hidden;
  background: linear-gradient(120deg, rgba(101,20,255,0.1), transparent);
}
.about-hero-num {
  position: absolute;
  top: 50%;
  right: 4%;
  transform: translateY(-50%);
  font-family: var(--ff-heading);
  font-weight: 700;
  font-size: clamp(4rem, 15vw, 10rem);
  color: rgba(191,0,255,0.08);
  user-select: none;
  pointer-events: none;
}
.about-hero h1 {
  font-size: clamp(1.75rem, 4vw, 2.75rem);
  color: #fff;
  margin-bottom: var(--gap-sm);
  position: relative;
  z-index: 1;
}
.about-desc {
  font-size: 1.05rem;
  color: var(--c-text-muted);
  max-width: 560px;
  position: relative;
  z-index: 1;
}
.about-body-section {
  display: flex;
  gap: var(--gap-xl);
  align-items: flex-start;
}
.about-aside h2, .about-aside h3 { font-size: 1rem; margin-bottom: 8px; }
.about-prose {
  flex: 1;
  min-width: 0;
  font-size: 1rem;
  line-height: 1.85;
  color: var(--c-text-muted);
  max-width: var(--prose-w);
}
.about-prose h2 { font-size: 1.4rem; color: #fff; margin: 2em 0 0.75em; }
.about-prose h3 { font-size: 1.15rem; color: var(--c-primary-light); margin: 1.5em 0 0.5em; }
.about-prose p { margin-bottom: 1.2em; }

/* ===== 隐私页 ===== */
.privacy-main {
  position: relative;
  z-index: 1;
}
.privacy-main > div > section {
  padding: var(--gap-lg) var(--gap-md);
  max-width: var(--max-w);
  margin: 0 auto;
}
.privacy-header {
  padding: var(--gap-xl) var(--gap-md) var(--gap-lg) !important;
  border-bottom: 1px solid var(--c-border);
}
.privacy-header h1 {
  font-size: clamp(1.5rem, 3.5vw, 2.25rem);
  color: #fff;
  margin-bottom: var(--gap-sm);
}
.privacy-desc {
  font-size: 1rem;
  color: var(--c-text-muted);
  margin-bottom: var(--gap-sm);
}
.privacy-header time {
  font-size: 0.8rem;
  color: var(--c-text-dim);
  font-family: var(--ff-heading);
}
.privacy-body-section {
  display: flex;
  gap: var(--gap-xl);
  align-items: flex-start;
}
.privacy-aside h2 { font-size: 1rem; margin-bottom: 8px; }
.privacy-prose {
  flex: 1;
  min-width: 0;
  font-size: 1rem;
  line-height: 1.85;
  color: var(--c-text-muted);
  max-width: var(--prose-w);
}
.privacy-prose h2 { font-size: 1.3rem; color: #fff; margin: 2em 0 0.75em; }
.privacy-prose p { margin-bottom: 1.2em; }
.privacy-prose a { text-decoration: underline; }

/* ===== 动效 stagger ===== */
.stagger-list > * {
  opacity: 0;
  transform: translateY(24px);
  animation: staggerIn 400ms ease forwards;
  animation-delay: var(--card-delay, var(--item-delay, 0ms));
}
@keyframes staggerIn {
  to { opacity: 1; transform: translateY(0); }
}
@media (prefers-reduced-motion: reduce) {
  .stagger-list > * { opacity: 1; transform: none; animation: none; }
  @keyframes bgShift { to {} }
}

/* ===== 响应式 ===== */
@media (max-width: 900px) {
  .content-section,
  .topic-body-section,
  .article-content-section,
  .about-body-section,
  .privacy-body-section {
    flex-direction: column;
    gap: var(--gap-lg);
  }
  .home-aside,
  .topic-aside,
  .about-aside,
  .privacy-aside {
    width: 100%;
  }
  .article-aside {
    order: 0;
    width: 100%;
  }
  .topics-grid {
    grid-template-columns: repeat(auto-fill, minmax(160px, 1fr));
    gap: var(--gap-sm);
  }
  .recent-grid {
    grid-template-columns: 1fr 1fr;
  }
}

@media (max-width: 600px) {
  :root {
    --gap-lg: 32px;
    --gap-xl: 48px;
  }
  html { font-size: 17px; }
  .nav-inner { padding: 0 var(--gap-sm); }
  .home-main > div > section,
  .topic-main > div > section,
  .article-main > div > section,
  .about-main > div > section,
  .privacy-main > div > section,
  .topic-hero-content {
    padding-left: var(--gap-sm);
    padding-right: var(--gap-sm);
  }
  .hero-section { min-height: 55vh; padding: var(--gap-lg) var(--gap-sm) !important; }
  .hero-content h1 { font-size: 1.8rem; }
  .topics-grid { grid-template-columns: 1fr 1fr; }
  .recent-grid { grid-template-columns: 1fr; }
  .child-dt { flex-direction: column; gap: 6px; }
  .site-footer {
    flex-direction: column;
    align-items: flex-start;
    gap: 8px;
    text-align: left;
  }
  .hero-bg-text { font-size: 5rem; right: -4%; }
  .nav-search { display: none; }
}

@media (min-width: 901px) {
  .main-nav.is-open {
    display: block;
  }
  .main-nav ol {
    flex-wrap: nowrap;
    overflow-x: auto;
  }
}