@import url('https://fonts.googleapis.com/css2?family=DM+Sans:wght@400;500;700&family=Space+Grotesk:wght@400;500;600;700&display=swap');

/* ==============================
   CSS 自定义属性 & 重置
   ============================== */
:root {
  --c-white: #ffffff;
  --c-surface: #f5f5f5;
  --c-ink: #1f1f1f;
  --c-ink-60: rgba(31,31,31,0.6);
  --c-ink-30: rgba(31,31,31,0.3);
  --c-ink-10: rgba(31,31,31,0.08);
  --c-border: rgba(31,31,31,0.12);
  --c-accent: #1f1f1f;

  /* 阴影层级 4级 */
  --shadow-sm: 0 1px 3px rgba(31,31,31,0.08), 0 1px 2px rgba(31,31,31,0.06);
  --shadow-md: 0 4px 12px rgba(31,31,31,0.10), 0 2px 6px rgba(31,31,31,0.07);
  --shadow-lg: 0 8px 28px rgba(31,31,31,0.13), 0 4px 10px rgba(31,31,31,0.08);
  --shadow-xl: 0 20px 60px rgba(31,31,31,0.18), 0 8px 24px rgba(31,31,31,0.12);

  --font-head: 'Space Grotesk', 'DM Sans', system-ui, sans-serif;
  --font-body: 'DM Sans', 'Space Grotesk', system-ui, sans-serif;

  --radius-card: 18px;
  --radius-sm: 8px;
  --radius-btn: 10px;

  --header-h: 68px;
  --content-w: 1160px;
  --prose-w: 740px;

  --transition-std: 0.25s cubic-bezier(0.4,0,0.2,1);
}

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

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

body {
  font-family: var(--font-body);
  font-size: 1rem;
  line-height: 1.7;
  color: var(--c-ink);
  background: var(--c-white);
  overflow-x: hidden;
}

img { display: block; max-width: 100%; height: auto; }
a { color: inherit; text-decoration: none; }
ul, menu { list-style: none; }
button { cursor: pointer; border: none; background: none; font: inherit; }
summary { cursor: pointer; list-style: none; }
summary::-webkit-details-marker { display: none; }

/* ==============================
   层叠工具类
   ============================== */
.layer-card {
  position: relative;
  z-index: 1;
  background: var(--c-white);
  border: 1px solid var(--c-border);
  border-radius: var(--radius-card);
  box-shadow: var(--shadow-md);
  transition: transform var(--transition-std), box-shadow var(--transition-std);
}
.layer-card:hover {
  transform: translateY(-4px) translateZ(0);
  box-shadow: var(--shadow-xl);
}

/* ==============================
   站点整体包裹
   ============================== */
.site-wrap {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  position: relative;
  z-index: 0;
}

/* ==============================
   顶部导航（品牌居中，菜单两侧）
   ============================== */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  height: var(--header-h);
  background: rgba(255,255,255,0.85);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  border-bottom: 1px solid var(--c-border);
  box-shadow: var(--shadow-sm);
}

.header-inner {
  max-width: var(--content-w);
  margin: 0 auto;
  padding: 0 24px;
  height: 100%;
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  align-items: center;
  gap: 16px;
}

.site-brand {
  justify-self: center;
}

.brand-link {
  display: flex;
  align-items: center;
  gap: 8px;
  font-family: var(--font-head);
  font-weight: 700;
  font-size: 1.1rem;
  letter-spacing: -0.02em;
  color: var(--c-ink);
  white-space: nowrap;
}
.brand-link:hover { opacity: 0.75; }

.brand-mark { width: 32px; height: 32px; object-fit: contain; }
.brand-name { display: inline-block; }

/* nav 结构：details > summary + menu > li > a */
.nav-details { position: relative; }

.nav-toggle {
  display: none; /* 桌面隐藏 toggle，菜单常显 */
}

.nav-menu {
  display: flex;
  align-items: center;
  gap: 4px;
  flex-wrap: wrap;
}

.nav-menu--left { justify-content: flex-end; }
.nav-menu--right { justify-content: flex-start; }

.nav-menu li a {
  display: inline-flex;
  align-items: center;
  padding: 8px 12px;
  font-family: var(--font-head);
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--c-ink);
  border-radius: var(--radius-sm);
  transition: background var(--transition-std), color var(--transition-std);
  white-space: nowrap;
  min-height: 40px;
}

.nav-menu li a:hover,
.nav-menu li a[aria-current="page"] {
  background: var(--c-ink-10);
  color: var(--c-ink);
}

.nav-right {
  display: flex;
  align-items: center;
  gap: 8px;
}

.cta-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 10px 20px;
  min-height: 40px;
  background: var(--c-ink);
  color: var(--c-white);
  font-family: var(--font-head);
  font-size: 0.875rem;
  font-weight: 600;
  border-radius: var(--radius-btn);
  transition: opacity var(--transition-std), transform var(--transition-std);
  white-space: nowrap;
}
.cta-btn:hover { opacity: 0.82; transform: translateY(-1px); }

.cta-btn--header { flex-shrink: 0; }

/* nav-right 内部不重复显示 cta-btn 样式的 a 标签 */
.nav-menu .cta-btn { background: transparent; color: var(--c-ink); }

/* ==============================
   main flex grow
   ============================== */
main { flex: 1; }

/* ==============================
   section 通用
   ============================== */
.section-inner {
  max-width: var(--content-w);
  margin: 0 auto;
  padding: 0 24px;
}

.section-title {
  font-family: var(--font-head);
  font-size: clamp(1.3rem, 2.5vw, 1.75rem);
  font-weight: 700;
  letter-spacing: -0.03em;
  color: var(--c-ink);
  margin-bottom: 36px;
  padding-bottom: 16px;
  border-bottom: 2px solid var(--c-ink);
}

/* ==============================
   首页 Hero
   ============================== */
.hero-section {
  position: relative;
  min-height: 70vh;
  display: flex;
  align-items: center;
  overflow: hidden;
  background: var(--c-surface);
  padding: 80px 24px;
}

.hero-content-wrap {
  max-width: var(--content-w);
  margin: 0 auto;
  width: 100%;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 60px;
  align-items: center;
  position: relative;
  z-index: 2;
}

.hero-text { display: flex; flex-direction: column; gap: 20px; }

.hero-eyebrow {
  display: inline-block;
  font-family: var(--font-head);
  font-size: 0.8rem;
  font-weight: 600;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--c-ink-60);
  padding: 6px 14px;
  border: 1px solid var(--c-border);
  border-radius: 100px;
  background: var(--c-white);
  width: fit-content;
}

.hero-h1 {
  font-family: var(--font-head);
  font-size: clamp(2rem, 5vw, 3.5rem);
  font-weight: 700;
  letter-spacing: -0.04em;
  line-height: 1.15;
  color: var(--c-ink);
}

.hero-lead {
  font-size: clamp(1rem, 1.5vw, 1.125rem);
  color: var(--c-ink-60);
  line-height: 1.75;
  max-width: 480px;
}

.hero-actions {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
  margin-top: 8px;
}

.btn-primary {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 14px 28px;
  min-height: 48px;
  background: var(--c-ink);
  color: var(--c-white);
  font-family: var(--font-head);
  font-size: 0.95rem;
  font-weight: 600;
  border-radius: var(--radius-btn);
  transition: opacity var(--transition-std), transform var(--transition-std), box-shadow var(--transition-std);
  box-shadow: var(--shadow-md);
}
.btn-primary:hover {
  opacity: 0.85;
  transform: translateY(-2px);
  box-shadow: var(--shadow-lg);
}

.btn-ghost {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 14px 28px;
  min-height: 48px;
  background: transparent;
  color: var(--c-ink);
  font-family: var(--font-head);
  font-size: 0.95rem;
  font-weight: 600;
  border: 1.5px solid var(--c-ink);
  border-radius: var(--radius-btn);
  transition: background var(--transition-std), color var(--transition-std);
}
.btn-ghost:hover { background: var(--c-ink); color: var(--c-white); }

.hero-media {
  position: relative;
  z-index: 2;
  border-radius: var(--radius-card);
  overflow: hidden;
  box-shadow: var(--shadow-xl);
  aspect-ratio: 4/3;
}
.hero-media--empty {
  background: var(--c-ink-10);
  min-height: 300px;
}
.hero-img { width: 100%; height: 100%; object-fit: cover; }

/* 超大背景装饰文字 */
.hero-deco {
  position: absolute;
  right: -0.05em;
  bottom: -0.2em;
  font-family: var(--font-head);
  font-size: clamp(12rem, 25vw, 22rem);
  font-weight: 700;
  color: rgba(31,31,31,0.04);
  line-height: 1;
  pointer-events: none;
  user-select: none;
  z-index: 1;
  letter-spacing: -0.06em;
}

/* ==============================
   首页内容区
   ============================== */
.content-section, .page-content-area {
  padding: 80px 0;
}

.prose {
  max-width: var(--prose-w);
}

.prose h2 {
  font-family: var(--font-head);
  font-size: clamp(1.2rem, 2.2vw, 1.5rem);
  font-weight: 700;
  letter-spacing: -0.025em;
  margin-top: 2.5em;
  margin-bottom: 0.75em;
  color: var(--c-ink);
}
.prose h3 {
  font-family: var(--font-head);
  font-size: 1.15rem;
  font-weight: 600;
  margin-top: 2em;
  margin-bottom: 0.6em;
}
.prose p { margin-bottom: 1.25em; color: var(--c-ink); }
.prose ul, .prose ol { padding-left: 1.5em; margin-bottom: 1.25em; }
.prose li { margin-bottom: 0.5em; }
.prose a { text-decoration: underline; text-underline-offset: 3px; }
.prose a:hover { opacity: 0.7; }
.prose strong { font-weight: 600; }
.prose blockquote {
  border-left: 3px solid var(--c-ink);
  padding-left: 1.25em;
  color: var(--c-ink-60);
  margin: 1.5em 0;
  font-style: italic;
}

/* ==============================
   首页特色栏目网格
   ============================== */
.features-section {
  padding: 80px 0;
  background: var(--c-surface);
}

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

.feature-card {
  display: flex;
  flex-direction: column;
  overflow: hidden;
}

.card-media {
  overflow: hidden;
  border-radius: var(--radius-card) var(--radius-card) 0 0;
  aspect-ratio: 16/9;
}
.card-media img { width: 100%; height: 100%; object-fit: cover; transition: transform 0.4s ease; }
.feature-card:hover .card-media img { transform: scale(1.04); }

.card-body {
  padding: 24px 28px 28px;
  flex: 1;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.card-body h3 {
  font-family: var(--font-head);
  font-size: 1.15rem;
  font-weight: 600;
  letter-spacing: -0.02em;
  line-height: 1.3;
}
.card-body h3 a { color: var(--c-ink); }
.card-body h3 a:hover { opacity: 0.7; }
.card-body p { font-size: 0.9rem; color: var(--c-ink-60); line-height: 1.65; flex: 1; }

.card-link {
  display: inline-flex;
  align-items: center;
  font-family: var(--font-head);
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--c-ink);
  margin-top: 4px;
  transition: opacity var(--transition-std);
}
.card-link:hover { opacity: 0.6; }

/* ==============================
   首页最新文章
   ============================== */
.latest-section {
  padding: 80px 0;
}

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

.latest-card {
  padding: 24px;
  background: var(--c-surface);
  border-radius: var(--radius-card);
  border: 1px solid var(--c-border);
  display: flex;
  flex-direction: column;
  gap: 10px;
  transition: transform var(--transition-std), box-shadow var(--transition-std);
  box-shadow: var(--shadow-sm);
}
.latest-card:hover {
  transform: translateY(-3px) translateZ(0);
  box-shadow: var(--shadow-lg);
}

.latest-meta {
  display: flex;
  align-items: center;
  gap: 10px;
  flex-wrap: wrap;
}

.cat-tag {
  display: inline-block;
  padding: 3px 10px;
  font-size: 0.75rem;
  font-weight: 600;
  font-family: var(--font-head);
  background: var(--c-ink);
  color: var(--c-white);
  border-radius: 100px;
  text-decoration: none;
  transition: opacity var(--transition-std);
}
.cat-tag:hover { opacity: 0.75; }

.latest-meta time {
  font-size: 0.78rem;
  color: var(--c-ink-60);
  font-family: var(--font-head);
}

.latest-card h3 {
  font-family: var(--font-head);
  font-size: 1rem;
  font-weight: 600;
  line-height: 1.4;
  letter-spacing: -0.01em;
}
.latest-card h3 a { color: var(--c-ink); }
.latest-card h3 a:hover { opacity: 0.7; }
.latest-card p { font-size: 0.875rem; color: var(--c-ink-60); line-height: 1.65; }

/* ==============================
   Stagger 动画
   ============================== */
@media (prefers-reduced-motion: no-preference) {
  .stagger-list > li,
  .stagger-list > .child-item,
  .stagger-list > .latest-card {
    opacity: 0;
    transform: translateY(28px);
    animation: staggerIn 0.5s cubic-bezier(0.4,0,0.2,1) forwards;
    animation-delay: calc(var(--stagger, 0) * 0.09s + 0.1s);
  }

  @keyframes staggerIn {
    to { opacity: 1; transform: translateY(0); }
  }
}

/* ==============================
   栏目页 Hero
   ============================== */
.cat-hero-section {
  position: relative;
  background: var(--c-surface);
  padding: 72px 24px 64px;
  overflow: hidden;
}

.cat-hero-inner {
  max-width: var(--content-w);
  margin: 0 auto;
  position: relative;
  z-index: 2;
}

.cat-breadcrumb {
  font-size: 0.82rem;
  color: var(--c-ink-60);
  margin-bottom: 20px;
}
.cat-breadcrumb a { color: var(--c-ink-60); text-decoration: underline; text-underline-offset: 3px; }
.cat-breadcrumb a:hover { color: var(--c-ink); }

.cat-h1 {
  font-family: var(--font-head);
  font-size: clamp(2rem, 4.5vw, 3.2rem);
  font-weight: 700;
  letter-spacing: -0.04em;
  line-height: 1.2;
  color: var(--c-ink);
  margin-bottom: 16px;
  max-width: 760px;
}

.cat-desc {
  font-size: 1.05rem;
  color: var(--c-ink-60);
  max-width: 600px;
  line-height: 1.75;
}

.cat-deco {
  position: absolute;
  right: 24px;
  top: 50%;
  transform: translateY(-50%);
  font-family: var(--font-head);
  font-size: clamp(8rem, 16vw, 14rem);
  font-weight: 700;
  color: rgba(31,31,31,0.05);
  line-height: 1;
  pointer-events: none;
  user-select: none;
  z-index: 1;
}

.cat-content-section {
  padding: 64px 0 48px;
}
.cat-content-section .section-inner { max-width: var(--content-w); }

/* 栏目子页列表 */
.cat-children-section {
  padding: 0 0 80px;
}

/* 子页列表：ul > li > article > h3/p */
.children-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 24px;
}

.child-card {
  display: flex;
  flex-direction: row;
  overflow: hidden;
}

.child-card-media {
  flex-shrink: 0;
  width: 180px;
  overflow: hidden;
  border-radius: var(--radius-card) 0 0 var(--radius-card);
}
.child-card-media img { width: 100%; height: 100%; object-fit: cover; }

.child-card-body {
  padding: 20px 24px;
  flex: 1;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.child-meta {
  font-size: 0.78rem;
  color: var(--c-ink-60);
  font-family: var(--font-head);
}

.child-card-body h3 {
  font-family: var(--font-head);
  font-size: 1.05rem;
  font-weight: 600;
  line-height: 1.35;
  letter-spacing: -0.015em;
}
.child-card-body h3 a { color: var(--c-ink); }
.child-card-body h3 a:hover { opacity: 0.7; }
.child-card-body p { font-size: 0.875rem; color: var(--c-ink-60); line-height: 1.65; flex: 1; }

.child-read-link {
  font-size: 0.82rem;
  font-weight: 600;
  font-family: var(--font-head);
  color: var(--c-ink);
  transition: opacity var(--transition-std);
}
.child-read-link:hover { opacity: 0.6; }

/* 兄弟栏目 */
.cat-siblings-section { padding: 0 0 80px; }
.siblings-list {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
}
.sibling-link {
  display: inline-flex;
  align-items: center;
  padding: 10px 20px;
  min-height: 42px;
  border: 1.5px solid var(--c-border);
  border-radius: 100px;
  font-size: 0.9rem;
  font-weight: 500;
  font-family: var(--font-head);
  color: var(--c-ink);
  background: var(--c-white);
  transition: background var(--transition-std), border-color var(--transition-std), box-shadow var(--transition-std);
  box-shadow: var(--shadow-sm);
}
.sibling-link:hover {
  background: var(--c-ink);
  color: var(--c-white);
  border-color: var(--c-ink);
  box-shadow: var(--shadow-md);
}

/* ==============================
   文章页
   ============================== */
.article-main { background: var(--c-white); }

.article-header-section {
  background: var(--c-surface);
  padding: 64px 24px 56px;
  position: relative;
}

.article-header-inner {
  max-width: var(--content-w);
  margin: 0 auto;
}

.article-breadcrumb {
  font-size: 0.82rem;
  color: var(--c-ink-60);
  margin-bottom: 16px;
}
.article-breadcrumb a { color: var(--c-ink-60); text-decoration: underline; text-underline-offset: 3px; }
.article-breadcrumb a:hover { color: var(--c-ink); }

.cat-badge {
  display: inline-block;
  padding: 4px 12px;
  background: var(--c-ink);
  color: var(--c-white);
  font-size: 0.78rem;
  font-weight: 600;
  font-family: var(--font-head);
  border-radius: 100px;
  margin-bottom: 16px;
  transition: opacity var(--transition-std);
}
.cat-badge:hover { opacity: 0.75; }

.article-h1 {
  font-family: var(--font-head);
  font-size: clamp(1.75rem, 4vw, 2.8rem);
  font-weight: 700;
  letter-spacing: -0.04em;
  line-height: 1.2;
  color: var(--c-ink);
  margin-bottom: 16px;
  max-width: 800px;
}

.article-lead {
  font-size: 1.05rem;
  color: var(--c-ink-60);
  line-height: 1.75;
  max-width: 680px;
  margin-bottom: 20px;
}

.article-meta-bar {
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
}

.meta-date {
  font-size: 0.82rem;
  color: var(--c-ink-60);
  font-family: var(--font-head);
}

.article-hero-media {
  max-width: var(--content-w);
  margin: 32px auto 0;
  border-radius: var(--radius-card);
  overflow: hidden;
  box-shadow: var(--shadow-xl);
}
.article-hero-img { width: 100%; max-height: 480px; object-fit: cover; }

/* 文章正文 + 侧边栏 */
.article-body-section {
  padding: 64px 0 80px;
}

.article-body-inner {
  max-width: var(--content-w);
  margin: 0 auto;
  padding: 0 24px;
  display: grid;
  grid-template-columns: 1fr 300px;
  gap: 56px;
  align-items: start;
}

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

.article-sidebar {
  position: sticky;
  top: calc(var(--header-h) + 24px);
  display: flex;
  flex-direction: column;
  gap: 20px;
}

.sidebar-back {
  margin-bottom: 4px;
}
.back-to-cat {
  font-size: 0.875rem;
  font-weight: 500;
  font-family: var(--font-head);
  color: var(--c-ink);
  padding: 8px 0;
  display: inline-block;
  transition: opacity var(--transition-std);
}
.back-to-cat:hover { opacity: 0.6; }

.sidebar-related, .sidebar-nav-links {
  background: var(--c-surface);
  border: 1px solid var(--c-border);
  border-radius: var(--radius-card);
  padding: 20px 24px;
  box-shadow: var(--shadow-sm);
}

.sidebar-heading {
  font-family: var(--font-head);
  font-size: 0.85rem;
  font-weight: 700;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--c-ink-60);
  margin-bottom: 14px;
  padding-bottom: 10px;
  border-bottom: 1px solid var(--c-border);
}

.sibling-article-list { display: flex; flex-direction: column; gap: 2px; }
.sibling-article-item a {
  display: flex;
  flex-direction: column;
  gap: 3px;
  padding: 10px 0;
  border-bottom: 1px solid var(--c-border);
  transition: opacity var(--transition-std);
}
.sibling-article-item:last-child a { border-bottom: none; }
.sibling-article-item a:hover { opacity: 0.65; }
.sib-title {
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--c-ink);
  line-height: 1.4;
}
.sib-date { font-size: 0.75rem; color: var(--c-ink-60); }

.sidebar-nav-ul { display: flex; flex-direction: column; gap: 2px; }
.sidebar-nav-ul li a {
  display: block;
  padding: 8px 0;
  font-size: 0.875rem;
  color: var(--c-ink);
  border-bottom: 1px solid var(--c-border);
  transition: opacity var(--transition-std);
}
.sidebar-nav-ul li:last-child a { border-bottom: none; }
.sidebar-nav-ul li a:hover { opacity: 0.65; }

/* ==============================
   关于页
   ============================== */
.about-hero-section {
  position: relative;
  background: var(--c-surface);
  padding: 80px 24px 72px;
  overflow: hidden;
}

.about-hero-inner {
  max-width: var(--content-w);
  margin: 0 auto;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 56px;
  align-items: center;
  position: relative;
  z-index: 2;
}

.about-eyebrow {
  display: inline-block;
  font-size: 0.8rem;
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--c-ink-60);
  border: 1px solid var(--c-border);
  padding: 5px 12px;
  border-radius: 100px;
  background: var(--c-white);
  margin-bottom: 16px;
  width: fit-content;
}

.about-h1 {
  font-family: var(--font-head);
  font-size: clamp(2rem, 4vw, 3rem);
  font-weight: 700;
  letter-spacing: -0.04em;
  line-height: 1.2;
  color: var(--c-ink);
  margin-bottom: 16px;
}

.about-lead {
  font-size: 1.05rem;
  color: var(--c-ink-60);
  line-height: 1.75;
}

.about-hero-media {
  border-radius: var(--radius-card);
  overflow: hidden;
  box-shadow: var(--shadow-xl);
}
.about-img { width: 100%; height: auto; object-fit: cover; }

.about-deco {
  position: absolute;
  left: -0.05em;
  bottom: -0.15em;
  font-family: var(--font-head);
  font-size: clamp(10rem, 20vw, 18rem);
  font-weight: 700;
  color: rgba(31,31,31,0.04);
  line-height: 1;
  pointer-events: none;
  user-select: none;
  z-index: 1;
}

.about-content-section {
  padding: 72px 0 80px;
}

.about-body-grid {
  display: grid;
  grid-template-columns: 1fr 320px;
  gap: 56px;
  align-items: start;
}

.about-prose { max-width: 100%; }

.about-aside {
  display: flex;
  flex-direction: column;
  gap: 20px;
  position: sticky;
  top: calc(var(--header-h) + 24px);
}

.aside-box {
  padding: 24px 28px;
}

.aside-heading {
  font-family: var(--font-head);
  font-size: 0.85rem;
  font-weight: 700;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--c-ink-60);
  margin-bottom: 16px;
  padding-bottom: 10px;
  border-bottom: 1px solid var(--c-border);
}

.about-nav-list { display: flex; flex-direction: column; gap: 4px; }
.about-nav-list li a {
  display: block;
  padding: 9px 0;
  font-size: 0.9rem;
  color: var(--c-ink);
  border-bottom: 1px solid var(--c-border);
  transition: opacity var(--transition-std);
}
.about-nav-list li:last-child a { border-bottom: none; }
.about-nav-list li a:hover { opacity: 0.65; }

.aside-brand-box p {
  font-size: 0.875rem;
  color: var(--c-ink-60);
  line-height: 1.65;
  margin-bottom: 16px;
}

.aside-home-btn {
  width: 100%;
  text-align: center;
  padding: 12px 20px;
}

/* ==============================
   隐私页
   ============================== */
.privacy-header-section {
  background: var(--c-surface);
  padding: 64px 24px 56px;
}

.privacy-header-inner {
  max-width: var(--content-w);
  margin: 0 auto;
}

.privacy-eyebrow {
  display: inline-block;
  font-size: 0.78rem;
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--c-ink-60);
  border: 1px solid var(--c-border);
  padding: 5px 12px;
  border-radius: 100px;
  background: var(--c-white);
  margin-bottom: 16px;
}

.privacy-h1 {
  font-family: var(--font-head);
  font-size: clamp(1.75rem, 3.5vw, 2.5rem);
  font-weight: 700;
  letter-spacing: -0.04em;
  line-height: 1.2;
  color: var(--c-ink);
  margin-bottom: 14px;
}

.privacy-updated {
  font-size: 0.85rem;
  color: var(--c-ink-60);
  font-family: var(--font-head);
}

.privacy-content-section {
  padding: 64px 0 80px;
}

.privacy-body-wrap {
  display: grid;
  grid-template-columns: 1fr 280px;
  gap: 56px;
  align-items: start;
  max-width: var(--content-w);
  margin: 0 auto;
  padding: 0 24px;
}

.privacy-prose { max-width: 100%; }

.privacy-aside {
  position: sticky;
  top: calc(var(--header-h) + 24px);
}

.privacy-nav-list { display: flex; flex-direction: column; gap: 4px; }
.privacy-nav-list li a {
  display: block;
  padding: 9px 0;
  font-size: 0.9rem;
  color: var(--c-ink);
  border-bottom: 1px solid var(--c-border);
  transition: opacity var(--transition-std);
}
.privacy-nav-list li:last-child a { border-bottom: none; }
.privacy-nav-list li a:hover { opacity: 0.65; }

/* ==============================
   页脚
   ============================== */
.site-footer {
  background: var(--c-ink);
  color: var(--c-white);
  padding-top: 56px;
  margin-top: auto;
}

.footer-inner {
  max-width: var(--content-w);
  margin: 0 auto;
  padding: 0 24px 48px;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 48px;
}

.footer-brand-link .brand-name { color: var(--c-white); }
.footer-brand-link .brand-mark { filter: invert(1); }
.footer-brand-link:hover { opacity: 0.8; }

.footer-desc {
  font-size: 0.875rem;
  color: rgba(255,255,255,0.55);
  line-height: 1.7;
  margin-top: 12px;
  max-width: 320px;
}

.footer-nav ul {
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.footer-nav ul li a {
  display: block;
  padding: 8px 0;
  font-size: 0.875rem;
  color: rgba(255,255,255,0.65);
  border-bottom: 1px solid rgba(255,255,255,0.1);
  transition: color var(--transition-std);
  min-height: 40px;
  display: flex;
  align-items: center;
}
.footer-nav ul li:last-child a { border-bottom: none; }
.footer-nav ul li a:hover { color: var(--c-white); }

.footer-bottom {
  border-top: 1px solid rgba(255,255,255,0.1);
  padding: 20px 24px;
  max-width: 100%;
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 12px;
}

.copyright {
  font-size: 0.8rem;
  color: rgba(255,255,255,0.45);
  font-family: var(--font-head);
}

.footer-legal {
  display: flex;
  gap: 20px;
}

.footer-legal a {
  font-size: 0.8rem;
  color: rgba(255,255,255,0.45);
  min-height: 40px;
  display: inline-flex;
  align-items: center;
  transition: color var(--transition-std);
}
.footer-legal a:hover { color: var(--c-white); }

/* ==============================
   视差滚动（Parallax）
   ============================== */
@media (prefers-reduced-motion: no-preference) {
  .hero-deco, .cat-deco, .about-deco {
    will-change: transform;
  }
}

/* ==============================
   响应式：平板 ≤900px
   ============================== */
@media (max-width: 900px) {
  .header-inner {
    grid-template-columns: auto 1fr auto;
    gap: 8px;
  }

  .nav-toggle {
    display: inline-flex;
    align-items: center;
    padding: 8px 14px;
    min-height: 40px;
    font-family: var(--font-head);
    font-size: 0.85rem;
    font-weight: 600;
    color: var(--c-ink);
    border: 1px solid var(--c-border);
    border-radius: var(--radius-sm);
    background: transparent;
    transition: background var(--transition-std);
  }
  .nav-toggle:hover { background: var(--c-ink-10); }

  .nav-details[open] .nav-menu {
    position: absolute;
    top: calc(100% + 8px);
    background: var(--c-white);
    border: 1px solid var(--c-border);
    border-radius: var(--radius-card);
    box-shadow: var(--shadow-xl);
    padding: 12px;
    flex-direction: column;
    gap: 4px;
    z-index: 200;
    min-width: 200px;
  }

  .nav-left .nav-details[open] .nav-menu { left: 0; }
  .nav-right .nav-details[open] .nav-menu { right: 0; }

  .nav-menu--left, .nav-menu--right { display: none; }
  .nav-details[open] .nav-menu--left,
  .nav-details[open] .nav-menu--right { display: flex; }

  .hero-content-wrap {
    grid-template-columns: 1fr;
    gap: 40px;
  }
  .hero-media { order: -1; }

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

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

  .article-body-inner {
    grid-template-columns: 1fr;
  }
  .article-sidebar {
    position: static;
  }

  .about-hero-inner {
    grid-template-columns: 1fr;
    gap: 32px;
  }

  .about-body-grid {
    grid-template-columns: 1fr;
  }
  .about-aside { position: static; }

  .privacy-body-wrap {
    grid-template-columns: 1fr;
  }
  .privacy-aside { position: static; }

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

/* ==============================
   响应式：手机 ≤480px
   ============================== */
@media (max-width: 480px) {
  :root { --header-h: 60px; }

  .header-inner { padding: 0 16px; gap: 6px; }
  .brand-name { font-size: 0.95rem; }
  .cta-btn--header { display: none; }

  .hero-section { min-height: auto; padding: 56px 16px 48px; }
  .hero-h1 { font-size: 1.9rem; }
  .hero-deco { font-size: 9rem; }

  .section-inner { padding: 0 16px; }
  .content-section, .page-content-area { padding: 56px 0; }
  .features-section { padding: 56px 0; }
  .latest-section { padding: 56px 0; }

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

  .cat-hero-section { padding: 56px 16px 48px; }
  .cat-h1 { font-size: 1.8rem; }
  .cat-deco { font-size: 7rem; }

  .article-header-section { padding: 48px 16px 40px; }
  .article-h1 { font-size: 1.65rem; }
  .article-body-section { padding: 40px 0 56px; }
  .article-body-inner { padding: 0 16px; }

  .about-hero-section { padding: 56px 16px 48px; }
  .about-h1 { font-size: 1.8rem; }
  .about-content-section { padding: 48px 0 56px; }
  .about-body-grid { gap: 32px; }

  .privacy-header-section { padding: 48px 16px 40px; }
  .privacy-content-section { padding: 40px 0 56px; }
  .privacy-body-wrap { padding: 0 16px; gap: 32px; }

  .footer-inner { padding: 0 16px 36px; }
  .footer-bottom { padding: 16px; flex-direction: column; align-items: flex-start; }

  .child-card { flex-direction: column; }
  .child-card-media { width: 100%; border-radius: var(--radius-card) var(--radius-card) 0 0; }
}