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

/* ===== 基础变量 ===== */
:root {
  --paper: #fdfbf7;
  --paper-2: #f5f5f5;
  --ink: #1a1a1a;
  --ink-light: #3a3a3a;
  --ink-muted: #6a6a6a;
  --border: #d8d4cc;
  --border-light: #e8e4dc;
  --radius-card: 28px;
  --radius-sm: 6px;
  --font-serif: 'Playfair Display', Georgia, 'Songti SC', serif;
  --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Helvetica Neue', Arial, sans-serif;
  --header-h: 64px;
  --max-w: 1200px;
  --content-w: 720px;
}

/* ===== 重置 ===== */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { font-size: 16px; scroll-behavior: smooth; }
body {
  background: var(--paper);
  color: var(--ink);
  font-family: var(--font-sans);
  font-size: 1rem;
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
  position: relative;
}
img { display: block; max-width: 100%; height: auto; }
a { color: var(--ink); text-decoration: none; }
a:hover { text-decoration: underline; }
ul, ol { list-style: none; }

/* ===== 纸质纹理覆盖层 ===== */
.paper-texture {
  position: fixed;
  inset: 0;
  pointer-events: none;
  z-index: 9999;
  opacity: 0.03;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='300' height='300'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.75' numOctaves='4' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='300' height='300' filter='url(%23n)' opacity='1'/%3E%3C/svg%3E");
}

/* ===== 顶部导航 ===== */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: var(--paper);
  border-bottom: 1px solid var(--border);
  height: auto;
}
.header-inner {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 0 24px;
  height: var(--header-h);
  display: flex;
  align-items: center;
  gap: 24px;
}
.brand-logo {
  display: flex;
  align-items: center;
  gap: 8px;
  flex-shrink: 0;
  text-decoration: none;
}
.logo-img { width: 32px; height: 32px; object-fit: contain; }
.brand-name {
  font-family: var(--font-serif);
  font-weight: 700;
  font-size: 1.1rem;
  letter-spacing: 0.02em;
  color: var(--ink);
  white-space: nowrap;
}
.main-nav {
  flex: 1;
  overflow: hidden;
}
.nav-links {
  display: flex;
  gap: 4px;
  flex-wrap: nowrap;
  overflow-x: auto;
  scrollbar-width: none;
  -ms-overflow-style: none;
}
.nav-links::-webkit-scrollbar { display: none; }
.nav-link {
  font-size: 0.78rem;
  font-weight: 500;
  color: var(--ink-light);
  padding: 8px 10px;
  white-space: nowrap;
  border-radius: var(--radius-sm);
  border: 1px solid transparent;
  min-height: 40px;
  display: flex;
  align-items: center;
  transition: none;
}
.nav-link:hover,
.nav-link--active {
  background: var(--paper-2);
  border-color: var(--border);
  color: var(--ink);
  text-decoration: none;
}
.cta-btn {
  flex-shrink: 0;
  background: var(--ink);
  color: var(--paper);
  font-size: 0.82rem;
  font-weight: 600;
  padding: 10px 18px;
  border-radius: var(--radius-sm);
  white-space: nowrap;
  min-height: 40px;
  display: flex;
  align-items: center;
  letter-spacing: 0.03em;
}
.cta-btn:hover { background: var(--ink-light); text-decoration: none; }
.mobile-menu-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 40px;
  height: 40px;
  background: none;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  cursor: pointer;
  padding: 8px;
}
.mobile-menu-toggle span {
  display: block;
  height: 2px;
  background: var(--ink);
  border-radius: 1px;
}
.mobile-nav {
  display: none;
  flex-direction: column;
  border-top: 1px solid var(--border);
  background: var(--paper);
  padding: 12px 24px 16px;
  gap: 4px;
}
.mobile-nav.is-open { display: flex; }
.mobile-nav-link {
  font-size: 0.9rem;
  color: var(--ink-light);
  padding: 12px 8px;
  border-bottom: 1px solid var(--border-light);
  min-height: 44px;
  display: flex;
  align-items: center;
}
.mobile-nav-link:last-child { border-bottom: none; }

/* ===== 通用按钮 ===== */
.btn-primary {
  display: inline-flex;
  align-items: center;
  background: var(--ink);
  color: var(--paper);
  font-size: 0.88rem;
  font-weight: 600;
  padding: 12px 24px;
  border-radius: var(--radius-sm);
  min-height: 44px;
  letter-spacing: 0.03em;
}
.btn-primary:hover { background: var(--ink-light); text-decoration: none; }
.btn-secondary {
  display: inline-flex;
  align-items: center;
  background: transparent;
  color: var(--ink);
  font-size: 0.88rem;
  font-weight: 500;
  padding: 11px 22px;
  border-radius: var(--radius-sm);
  border: 1px solid var(--ink);
  min-height: 44px;
}
.btn-secondary:hover { background: var(--paper-2); text-decoration: none; }
.btn-ghost {
  display: inline-flex;
  align-items: center;
  background: transparent;
  color: var(--ink-light);
  font-size: 0.88rem;
  font-weight: 500;
  padding: 11px 22px;
  border-radius: var(--radius-sm);
  border: 1px solid var(--border);
  min-height: 44px;
}
.btn-ghost:hover { border-color: var(--ink); color: var(--ink); text-decoration: none; }

/* ===== 首页：Hero ===== */
.hero-section {
  position: relative;
  min-height: 45vh;
  display: grid;
  grid-template-columns: 1fr;
  align-items: center;
  justify-items: center;
  text-align: center;
  overflow: hidden;
  border-bottom: 1px solid var(--border);
  padding: 60px 24px 40px;
}
.hero-bg-text {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  font-family: var(--font-serif);
  font-size: clamp(80px, 18vw, 200px);
  font-weight: 700;
  color: var(--paper-2);
  letter-spacing: -0.05em;
  pointer-events: none;
  user-select: none;
  white-space: nowrap;
  line-height: 1;
}
.hero-aside {
  position: absolute;
  top: 20px;
  left: 24px;
  z-index: 2;
}
.hero-eyebrow {
  font-size: 0.72rem;
  font-weight: 600;
  letter-spacing: 0.15em;
  color: var(--ink-muted);
  border: 1px solid var(--border);
  padding: 4px 10px;
  border-radius: 2px;
}
.hero-content {
  position: relative;
  z-index: 2;
  max-width: 700px;
}
.hero-h1 {
  font-family: var(--font-serif);
  font-size: clamp(1.8rem, 5vw, 3.2rem);
  font-weight: 700;
  line-height: 1.2;
  letter-spacing: -0.01em;
  margin-bottom: 16px;
}
.hero-desc {
  font-size: 1rem;
  color: var(--ink-muted);
  max-width: 520px;
  margin: 0 auto 28px;
  line-height: 1.7;
}
.hero-actions {
  display: flex;
  gap: 12px;
  justify-content: center;
  flex-wrap: wrap;
}
.hero-figure {
  position: absolute;
  bottom: 0;
  right: 0;
  width: 40%;
  max-width: 400px;
  opacity: 0.08;
  pointer-events: none;
  z-index: 1;
}
.hero-img { width: 100%; height: auto; }
.hero-placeholder {
  width: 100%;
  height: 200px;
  background: var(--border-light);
}

/* ===== 首页：内容区 ===== */
.content-section {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 60px 24px;
  display: grid;
  grid-template-columns: 220px 1fr;
  gap: 48px;
  align-items: start;
}
.content-aside {
  position: sticky;
  top: calc(var(--header-h) + 20px);
}
.content-main { min-width: 0; }

/* ===== 文章区块 ===== */
.articles-section {
  background: var(--paper-2);
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
  padding: 60px 24px;
  position: relative;
}
.section-deco {
  position: absolute;
  top: 0; left: 0; right: 0; bottom: 0;
  background-image: repeating-linear-gradient(
    0deg,
    transparent,
    transparent 39px,
    var(--border-light) 39px,
    var(--border-light) 40px
  );
  pointer-events: none;
  opacity: 0.4;
}
.articles-inner {
  position: relative;
  z-index: 1;
  max-width: var(--max-w);
  margin: 0 auto;
}
.section-title {
  font-family: var(--font-serif);
  font-size: 1.6rem;
  font-weight: 700;
  margin-bottom: 8px;
}
.section-title span { border-bottom: 2px solid var(--ink); padding-bottom: 2px; }
.section-sub {
  color: var(--ink-muted);
  font-size: 0.9rem;
  margin-bottom: 32px;
}

/* ===== 卡片列表 ===== */
.card-list {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 20px;
}
.card-list li { list-style: none; }
.card {
  background: var(--paper);
  border-radius: var(--radius-card);
  padding: 28px;
  border: 1px solid var(--border);
  display: flex;
  flex-direction: column;
  gap: 10px;
  height: 100%;
}
.card h3 {
  font-family: var(--font-serif);
  font-size: 1.05rem;
  font-weight: 700;
  line-height: 1.3;
}
.card h3 span { display: block; }
.card p {
  font-size: 0.88rem;
  color: var(--ink-muted);
  flex: 1;
  line-height: 1.6;
}
.card-date {
  font-size: 0.75rem;
  color: var(--ink-muted);
  letter-spacing: 0.05em;
}
.card-link {
  font-size: 0.82rem;
  font-weight: 600;
  color: var(--ink);
  border-bottom: 1px solid var(--ink);
  align-self: flex-start;
  padding-bottom: 1px;
}
.card:hover { border-color: var(--ink-muted); }

/* ===== 侧边栏 ===== */
.aside-title {
  font-family: var(--font-serif);
  font-size: 0.85rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  color: var(--ink-muted);
  margin-bottom: 12px;
  text-transform: uppercase;
}
.aside-title span { border-bottom: 1px solid var(--border); padding-bottom: 2px; }
.aside-title--mt { margin-top: 28px; }
.aside-link {
  display: block;
  font-size: 0.84rem;
  color: var(--ink-light);
  padding: 8px 0;
  border-bottom: 1px solid var(--border-light);
  line-height: 1.4;
  min-height: 40px;
  display: flex;
  align-items: center;
}
.aside-link:hover { color: var(--ink); text-decoration: none; }
.aside-inner-nav { display: flex; flex-direction: column; }
.article-tag {
  display: inline-block;
  font-size: 0.72rem;
  font-weight: 600;
  letter-spacing: 0.12em;
  color: var(--ink-muted);
  border: 1px solid var(--border);
  padding: 3px 8px;
  border-radius: 2px;
  margin-bottom: 12px;
}
.article-date, .article-date-mod {
  display: block;
  font-size: 0.78rem;
  color: var(--ink-muted);
  margin-top: 4px;
}

/* ===== 文章布局 ===== */
.article-main, .about-main, .privacy-main { min-height: calc(100vh - var(--header-h)); }

.article-hero-section {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 40px 24px 32px;
  display: grid;
  grid-template-columns: 180px 1fr;
  gap: 32px;
  align-items: start;
  border-bottom: 1px solid var(--border);
}
.article-hero-aside { grid-column: 1; }
.article-hero-figure { display: none; }
.article-hero-text { grid-column: 2; }
.article-h1 {
  font-family: var(--font-serif);
  font-size: clamp(1.6rem, 4vw, 2.6rem);
  font-weight: 700;
  line-height: 1.2;
  letter-spacing: -0.01em;
  margin-bottom: 12px;
}
.article-lead {
  font-size: 1rem;
  color: var(--ink-muted);
  line-height: 1.7;
  max-width: 600px;
}

.article-body-section,
.about-body-section,
.privacy-body-section {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 48px 24px 64px;
  display: grid;
  grid-template-columns: 220px 1fr;
  gap: 48px;
  align-items: start;
}
.article-sidebar {
  position: sticky;
  top: calc(var(--header-h) + 20px);
  min-width: 0;
}
.sidebar-sticky {}
.article-content { min-width: 0; max-width: var(--content-w); }
.article-content-figure { margin-bottom: 24px; }
.article-rule {
  height: 1px;
  background: var(--border);
  width: 100%;
}
.article-footer-nav {
  display: flex;
  gap: 12px;
  margin-top: 48px;
  flex-wrap: wrap;
}
.aside-related-link {
  display: flex;
  flex-direction: column;
  gap: 3px;
  padding: 10px 0;
  border-bottom: 1px solid var(--border-light);
  min-height: 44px;
  justify-content: center;
}
.aside-related-link:hover { text-decoration: none; }
.related-title {
  font-size: 0.83rem;
  color: var(--ink-light);
  line-height: 1.4;
}
.aside-related-link:hover .related-title { color: var(--ink); }
.related-date {
  font-size: 0.72rem;
  color: var(--ink-muted);
}

/* ===== 关于页 ===== */
.about-intro-section {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 40px 24px 32px;
  display: grid;
  grid-template-columns: 180px 1fr;
  gap: 32px;
  align-items: start;
  border-bottom: 1px solid var(--border);
  position: relative;
  overflow: hidden;
}
.about-aside { grid-column: 1; }
.about-figure { display: none; }
.about-intro-text { grid-column: 2; }
.about-bg-num {
  position: absolute;
  right: -20px;
  bottom: -20px;
  font-family: var(--font-serif);
  font-size: clamp(60px, 12vw, 140px);
  font-weight: 700;
  color: var(--paper-2);
  pointer-events: none;
  user-select: none;
  line-height: 1;
}
.about-h1 {
  font-family: var(--font-serif);
  font-size: clamp(1.6rem, 4vw, 2.6rem);
  font-weight: 700;
  line-height: 1.2;
  margin-bottom: 12px;
}
.about-lead {
  font-size: 1rem;
  color: var(--ink-muted);
  line-height: 1.7;
}

/* ===== 隐私页 ===== */
.privacy-header-section {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 40px 24px 32px;
  display: grid;
  grid-template-columns: 180px 1fr;
  gap: 32px;
  align-items: start;
  border-bottom: 1px solid var(--border);
  position: relative;
  overflow: hidden;
}
.privacy-aside { grid-column: 1; }
.privacy-figure { display: none; }
.privacy-header-text { grid-column: 2; }
.privacy-bg-text {
  position: absolute;
  right: -10px;
  bottom: -10px;
  font-family: var(--font-serif);
  font-size: clamp(50px, 10vw, 120px);
  font-weight: 700;
  color: var(--paper-2);
  pointer-events: none;
  user-select: none;
  line-height: 1;
  letter-spacing: -0.03em;
}
.privacy-h1 {
  font-family: var(--font-serif);
  font-size: clamp(1.6rem, 4vw, 2.6rem);
  font-weight: 700;
  line-height: 1.2;
  margin-bottom: 12px;
}
.privacy-lead {
  font-size: 1rem;
  color: var(--ink-muted);
  line-height: 1.7;
}

/* ===== Default 布局 ===== */
.default-section {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 48px 24px 64px;
  display: grid;
  grid-template-columns: 220px 1fr;
  gap: 48px;
  align-items: start;
}
.default-figure { margin-bottom: 24px; }
.default-content { min-width: 0; max-width: var(--content-w); }

/* ===== 正文排版 ===== */
.prose {
  font-size: 1rem;
  line-height: 1.8;
  color: var(--ink);
}
.prose h2 {
  font-family: var(--font-serif);
  font-size: 1.4rem;
  font-weight: 700;
  margin: 2em 0 0.6em;
  line-height: 1.3;
}
.prose h3 {
  font-family: var(--font-serif);
  font-size: 1.15rem;
  font-weight: 700;
  margin: 1.6em 0 0.5em;
}
.prose p { margin-bottom: 1.2em; }
.prose ul, .prose ol {
  margin: 0.8em 0 1.2em 1.4em;
}
.prose ul { list-style: disc; }
.prose ol { list-style: decimal; }
.prose li { margin-bottom: 0.4em; }
.prose a { border-bottom: 1px solid var(--border); }
.prose a:hover { border-color: var(--ink); text-decoration: none; }
.prose strong { font-weight: 600; }
.prose blockquote {
  border-left: 3px solid var(--border);
  padding-left: 20px;
  color: var(--ink-muted);
  margin: 1.5em 0;
  font-style: italic;
}
.prose time { font-size: 0.85em; color: var(--ink-muted); }
.prose hr { border: none; border-top: 1px solid var(--border); margin: 2em 0; }
.article-prose { max-width: var(--content-w); }

/* ===== 页脚 ===== */
.site-footer {
  background: var(--paper-2);
  border-top: 2px solid var(--ink);
  margin-top: 0;
}
.footer-subscribe {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 48px 24px 40px;
  border-bottom: 1px solid var(--border);
}
.footer-form-title {
  font-family: var(--font-serif);
  font-size: 1.4rem;
  font-weight: 700;
  margin-bottom: 8px;
}
.footer-form-title span { border-bottom: 2px solid var(--ink); padding-bottom: 2px; }
.footer-subscribe p {
  color: var(--ink-muted);
  font-size: 0.9rem;
  margin-bottom: 20px;
}
.footer-cta-row {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
}
.footer-cols {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 40px 24px 32px;
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 32px;
  border-bottom: 1px solid var(--border);
}
.footer-dl dt {
  font-family: var(--font-serif);
  font-size: 0.9rem;
  font-weight: 700;
  margin-bottom: 12px;
  color: var(--ink);
  letter-spacing: 0.03em;
}
.footer-dl dd { margin: 0; }
.footer-dl dd a,
.footer-dl dt a {
  display: block;
  font-size: 0.84rem;
  color: var(--ink-muted);
  padding: 5px 0;
  border-bottom: 1px solid var(--border-light);
  min-height: 34px;
  display: flex;
  align-items: center;
  line-height: 1.4;
}
.footer-dl dd a:hover,
.footer-dl dt a:hover { color: var(--ink); text-decoration: none; }
.footer-nav-dl {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 20px 24px;
  border-bottom: 1px solid var(--border);
}
.footer-nav-dl dl {
  display: flex;
  flex-wrap: wrap;
  gap: 4px 16px;
}
.footer-nav-dl dt, .footer-nav-dl dd { margin: 0; }
.footer-nav-dl dt a, .footer-nav-dl dd a {
  font-size: 0.8rem;
  color: var(--ink-muted);
  padding: 6px 4px;
  min-height: 40px;
  display: flex;
  align-items: center;
}
.footer-nav-dl dt a:hover, .footer-nav-dl dd a:hover { color: var(--ink); text-decoration: none; }
.footer-bar {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 16px 24px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 8px;
  font-size: 0.78rem;
  color: var(--ink-muted);
}
.footer-bar a {
  color: var(--ink-muted);
  border-bottom: 1px solid var(--border);
  padding-bottom: 1px;
  min-height: 40px;
  display: inline-flex;
  align-items: center;
}
.footer-bar a:hover { color: var(--ink); text-decoration: none; }

/* ===== Parallax / 微交互 ===== */
.card {
  will-change: transform;
  transition: border-color 0.15s ease, box-shadow 0.15s ease;
}
.card:hover {
  box-shadow: 0 4px 20px rgba(26,26,26,0.07);
}
.aside-link,
.nav-link,
.cta-btn,
.btn-primary,
.btn-secondary,
.btn-ghost {
  transition: background-color 0.12s ease, color 0.12s ease, border-color 0.12s ease;
}

/* ===== prefers-reduced-motion ===== */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    transition: none !important;
    animation: none !important;
  }
  html { scroll-behavior: auto; }
}

/* ===== 响应式：平板 ===== */
@media (max-width: 900px) {
  .content-section,
  .article-hero-section,
  .article-body-section,
  .about-intro-section,
  .about-body-section,
  .privacy-header-section,
  .privacy-body-section,
  .default-section {
    grid-template-columns: 1fr;
  }
  .article-sidebar,
  .content-aside {
    position: static;
  }
  .article-sidebar { order: -1; }
  .article-hero-aside,
  .about-aside,
  .privacy-aside { grid-column: 1; }
  .article-hero-text,
  .about-intro-text,
  .privacy-header-text { grid-column: 1; }
  .footer-cols { grid-template-columns: repeat(2, 1fr); }
}

/* ===== 响应式：移动端 ===== */
@media (max-width: 640px) {
  :root { --header-h: 56px; }
  .main-nav { display: none; }
  .cta-btn { display: none; }
  .mobile-menu-toggle { display: flex; }
  .hero-section { padding: 48px 16px 36px; min-height: 40vh; }
  .hero-h1 { font-size: 1.7rem; }
  .hero-bg-text { font-size: 20vw; }
  .hero-actions { flex-direction: column; align-items: center; }
  .btn-primary, .btn-secondary, .btn-ghost { width: 100%; justify-content: center; }
  .card-list { grid-template-columns: 1fr; }
  .content-section,
  .article-body-section,
  .about-body-section,
  .privacy-body-section,
  .articles-section,
  .default-section { padding: 32px 16px 48px; }
  .article-hero-section,
  .about-intro-section,
  .privacy-header-section { padding: 28px 16px 24px; }
  .footer-cols { grid-template-columns: 1fr; padding: 28px 16px; }
  .footer-subscribe { padding: 32px 16px; }
  .footer-bar { padding: 14px 16px; flex-direction: column; align-items: flex-start; }
  .article-h1, .about-h1, .privacy-h1 { font-size: 1.5rem; }
  .section-title { font-size: 1.3rem; }
  .footer-form-title { font-size: 1.2rem; }
  .header-inner { padding: 0 16px; gap: 12px; }
  .mobile-nav { padding: 12px 16px 16px; }
  .footer-nav-dl { padding: 16px; }
}