/* ===== 字体 ===== */
@import url('https://fonts.googleapis.com/css2?family=Cormorant+Infant:wght@300;400;500;600;700&family=Great+Vibes&display=swap');

/* ===== 自定义属性 ===== */
:root {
  --color-ink: #000000;
  --color-paper: #ffffff;
  --color-rule: #000000;
  --color-mid: #444444;
  --color-dim: #888888;
  --color-pale: #f4f4f4;
  --color-accent: #000000;
  --sidebar-w: 240px;
  --gap: 2rem;
  --radius: 4px;
  --font-body: 'Cormorant Infant', 'Noto Serif SC', Georgia, serif;
  --font-script: 'Great Vibes', cursive;
  --font-mono: 'Courier New', monospace;
  --transition: 220ms ease;
  --max-prose: 720px;
}

/* ===== 重置 ===== */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { font-size: 17px; scroll-behavior: smooth; }
body {
  font-family: var(--font-body);
  font-weight: 400;
  color: var(--color-ink);
  background: var(--color-paper);
  line-height: 1.65;
  -webkit-text-size-adjust: 100%;
}
img { max-width: 100%; height: auto; display: block; }
a { color: inherit; text-decoration: none; }
ul, ol { list-style: none; }
button { cursor: pointer; border: none; background: none; font: inherit; }

/* ===== 布局骨架 ===== */
.layout-wrapper {
  display: grid;
  grid-template-columns: var(--sidebar-w) 1fr;
  min-height: 100vh;
}

/* ===== 侧边栏 ===== */
.sidebar {
  position: fixed;
  top: 0;
  left: 0;
  width: var(--sidebar-w);
  height: 100vh;
  background: var(--color-ink);
  color: var(--color-paper);
  display: flex;
  flex-direction: column;
  z-index: 200;
  border-right: 2px solid var(--color-ink);
  overflow-y: auto;
  transition: transform var(--transition);
}

.sidebar__brand {
  padding: 1.5rem 1.25rem 1rem;
  border-bottom: 1px solid rgba(255,255,255,0.15);
}

.brand-link {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  text-decoration: none;
}

.brand-logo {
  width: 28px;
  height: 28px;
  object-fit: contain;
}

.brand-script {
  font-family: var(--font-script);
  font-size: 1.55rem;
  color: var(--color-paper);
  line-height: 1.2;
  letter-spacing: 0.01em;
}

.sidebar__announce {
  font-size: 0.72rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: rgba(255,255,255,0.45);
  padding: 0.55rem 1.25rem;
  border-bottom: 1px solid rgba(255,255,255,0.1);
}

.sidebar__nav {
  flex: 1;
  padding: 1rem 0;
}

.nav-footer-inner {
  display: block;
}

.nav-dl {
  padding: 0 0.75rem;
}

.nav-dl__section {
  font-size: 0.68rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: rgba(255,255,255,0.35);
  padding: 0.5rem 0.5rem 0.25rem;
  display: block;
}

.nav-dl dd {
  display: block;
}

.nav-link {
  display: block;
  padding: 0.55rem 0.5rem;
  font-size: 0.88rem;
  color: rgba(255,255,255,0.75);
  border-radius: var(--radius);
  transition: color var(--transition), background var(--transition);
  line-height: 1.4;
  min-height: 40px;
  display: flex;
  align-items: center;
}

.nav-link:hover {
  color: var(--color-paper);
  background: rgba(255,255,255,0.1);
}

.nav-link--active {
  color: var(--color-paper);
  background: rgba(255,255,255,0.15);
  font-weight: 600;
}

/* ===== 汉堡按钮 ===== */
.nav-toggle {
  display: none;
  position: fixed;
  top: 1rem;
  left: 1rem;
  z-index: 300;
  width: 44px;
  height: 44px;
  background: var(--color-ink);
  color: var(--color-paper);
  border-radius: var(--radius);
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 5px;
  padding: 0;
}

.nav-toggle__bar {
  display: block;
  width: 22px;
  height: 2px;
  background: var(--color-paper);
  transition: transform var(--transition), opacity var(--transition);
}

.nav-toggle[aria-expanded="true"] .nav-toggle__bar:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}
.nav-toggle[aria-expanded="true"] .nav-toggle__bar:nth-child(2) {
  opacity: 0;
}
.nav-toggle[aria-expanded="true"] .nav-toggle__bar:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

.nav-overlay {
  display: none;
  position: fixed;
  inset: 0;
  background: rgba(0,0,0,0.55);
  z-index: 190;
  opacity: 0;
  transition: opacity var(--transition);
}

/* ===== 主内容区 ===== */
.main-content {
  margin-left: var(--sidebar-w);
  min-width: 0;
  display: flex;
  flex-direction: column;
}

/* ===== 面包屑 ===== */
.guide-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1rem 2rem;
  border-bottom: 1px solid var(--color-ink);
  font-size: 0.82rem;
  gap: 1rem;
  flex-wrap: wrap;
}

.guide-header__meta {
  display: flex;
  align-items: center;
  gap: 0.4rem;
}

.breadcrumb-link {
  color: var(--color-mid);
  transition: color var(--transition);
}
.breadcrumb-link:hover { color: var(--color-ink); }

.breadcrumb-sep {
  color: var(--color-dim);
}

.breadcrumb-current {
  font-weight: 600;
}

.guide-header__date {
  color: var(--color-dim);
  font-size: 0.78rem;
  letter-spacing: 0.02em;
}

/* ===== Hero（首页专用）===== */
.hero {
  position: relative;
  min-height: 45vh;
  display: flex;
  align-items: flex-end;
  overflow: hidden;
  background: var(--color-ink);
  color: var(--color-paper);
}

.hero__slash {
  position: absolute;
  bottom: -2px;
  left: 0;
  right: 0;
  height: 64px;
  background: var(--color-paper);
  clip-path: polygon(0 100%, 100% 0, 100% 100%);
  z-index: 2;
}

.hero__body {
  position: relative;
  z-index: 3;
  padding: 3rem 2.5rem 5rem;
  max-width: 640px;
}

.hero__eyebrow {
  font-size: 0.75rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: rgba(255,255,255,0.5);
  margin-bottom: 0.75rem;
}

.hero__h1 {
  font-family: var(--font-body);
  font-size: clamp(1.75rem, 4vw, 2.8rem);
  font-weight: 700;
  line-height: 1.25;
  margin-bottom: 1rem;
}

.hero__sub {
  font-size: 1rem;
  color: rgba(255,255,255,0.75);
  max-width: 480px;
  margin-bottom: 1.75rem;
  line-height: 1.7;
}

.hero__actions {
  display: flex;
  gap: 0.75rem;
  flex-wrap: wrap;
}

/* ===== 按钮 ===== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  height: 44px;
  padding: 0 1.5rem;
  font-family: var(--font-body);
  font-size: 0.9rem;
  font-weight: 600;
  border-radius: var(--radius);
  transition: background var(--transition), color var(--transition), border-color var(--transition);
  border: 2px solid transparent;
  letter-spacing: 0.02em;
  white-space: nowrap;
}

.btn--primary {
  background: var(--color-paper);
  color: var(--color-ink);
  border-color: var(--color-paper);
}
.btn--primary:hover {
  background: rgba(255,255,255,0.88);
}

.btn--ghost {
  background: transparent;
  color: var(--color-paper);
  border-color: rgba(255,255,255,0.5);
}
.btn--ghost:hover {
  border-color: var(--color-paper);
  color: var(--color-paper);
}

.main-content .btn--ghost {
  color: var(--color-ink);
  border-color: var(--color-ink);
}
.main-content .btn--ghost:hover {
  background: var(--color-ink);
  color: var(--color-paper);
}

.main-content .btn--primary {
  background: var(--color-ink);
  color: var(--color-paper);
  border-color: var(--color-ink);
}
.main-content .btn--primary:hover {
  background: #222;
}

/* ===== 文章容器 ===== */
.page-article {
  flex: 1;
  padding: var(--gap) 2rem;
  max-width: 900px;
  width: 100%;
}

.page-article--guide,
.page-article--faq,
.page-article--changelog,
.page-article--about,
.page-article--privacy {
  max-width: 800px;
}

.article-header {
  padding-bottom: 1.5rem;
  border-bottom: 2px solid var(--color-ink);
  margin-bottom: 2rem;
}

.article-h1 {
  font-size: clamp(1.5rem, 3.5vw, 2.25rem);
  font-weight: 700;
  line-height: 1.25;
  margin-bottom: 0.75rem;
}

.article-desc {
  font-size: 1rem;
  color: var(--color-mid);
  line-height: 1.6;
  max-width: 580px;
}

/* ===== 正文 Prose ===== */
.content-section {
  margin-bottom: 3rem;
}

.prose {
  max-width: var(--max-prose);
  line-height: 1.75;
  font-size: 1rem;
}

.prose h2 {
  font-size: 1.35rem;
  font-weight: 700;
  margin: 2rem 0 0.75rem;
  padding-bottom: 0.35rem;
  border-bottom: 1px solid var(--color-ink);
}

.prose h3 {
  font-size: 1.1rem;
  font-weight: 600;
  margin: 1.5rem 0 0.5rem;
}

.prose h4 {
  font-size: 1rem;
  font-weight: 600;
  margin: 1.25rem 0 0.4rem;
}

.prose p {
  margin-bottom: 1rem;
}

.prose ul, .prose ol {
  padding-left: 1.25rem;
  margin-bottom: 1rem;
}

.prose ul { list-style: disc; }
.prose ol { list-style: decimal; }

.prose li {
  margin-bottom: 0.35rem;
  line-height: 1.7;
}

.prose a {
  text-decoration: underline;
  text-underline-offset: 3px;
  transition: opacity var(--transition);
}
.prose a:hover { opacity: 0.65; }

.prose strong { font-weight: 700; }
.prose em { font-style: italic; }

.prose code {
  font-family: var(--font-mono);
  font-size: 0.88em;
  background: var(--color-pale);
  padding: 0.15em 0.4em;
  border-radius: 3px;
}

.prose pre {
  background: var(--color-pale);
  border: 1px solid var(--color-ink);
  border-radius: var(--radius);
  padding: 1rem 1.25rem;
  overflow-x: auto;
  font-size: 0.88rem;
  line-height: 1.55;
  margin-bottom: 1.25rem;
}

.prose pre code {
  background: none;
  padding: 0;
}

.prose blockquote {
  border-left: 3px solid var(--color-ink);
  padding-left: 1rem;
  color: var(--color-mid);
  margin: 1.25rem 0;
}

.prose table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.92rem;
  margin-bottom: 1.25rem;
}

.prose th, .prose td {
  border: 1px solid var(--color-ink);
  padding: 0.5rem 0.75rem;
  text-align: left;
}

.prose th {
  background: var(--color-ink);
  color: var(--color-paper);
  font-weight: 600;
}

.prose time {
  font-size: 0.85rem;
  color: var(--color-mid);
  display: inline-block;
  margin-bottom: 0.5rem;
}

/* ===== 首页指南卡片网格 ===== */
.section-header {
  display: flex;
  align-items: baseline;
  gap: 1rem;
  margin-bottom: 1.25rem;
  padding-bottom: 0.75rem;
  border-bottom: 1px solid var(--color-ink);
}

.section-title {
  font-size: 1.15rem;
  font-weight: 700;
  letter-spacing: 0.02em;
}

.section-count {
  font-size: 0.78rem;
  color: var(--color-dim);
  letter-spacing: 0.06em;
}

.guide-grid-section {
  margin-bottom: 3rem;
}

.guide-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
  gap: 1rem;
}

.card {
  border: 1px solid var(--color-ink);
  border-radius: var(--radius);
  border-bottom: 4px solid var(--color-ink);
  transition: transform var(--transition), box-shadow var(--transition);
}

.card:hover {
  transform: translateY(-2px);
}

.card__inner {
  padding: 1.25rem;
  display: grid;
  grid-template-rows: auto 1fr auto;
  gap: 0.5rem;
  min-height: 160px;
}

.card__num {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--color-dim);
  letter-spacing: 0.08em;
}

.card__title {
  font-size: 0.95rem;
  font-weight: 700;
  line-height: 1.4;
}

.card__title a {
  text-decoration: none;
  transition: opacity var(--transition);
}

.card__title a:hover { opacity: 0.65; }

.card__desc {
  font-size: 0.82rem;
  color: var(--color-mid);
  line-height: 1.55;
}

.card__arrow {
  font-size: 1.1rem;
  align-self: end;
  justify-self: end;
  transition: transform var(--transition);
}

.card:hover .card__arrow {
  transform: translateX(3px);
}

/* 卡片交错动画 */
@media (prefers-reduced-motion: no-preference) {
  .card {
    animation: fadeUp 0.45s ease both;
    animation-delay: calc(var(--stagger, 0) * 60ms);
  }
}

@keyframes fadeUp {
  from { opacity: 0; transform: translateY(12px); }
  to   { opacity: 1; transform: translateY(0); }
}

/* ===== FAQ CTA ===== */
.faq-cta {
  margin-bottom: 2rem;
}

.faq-cta__inner {
  background: var(--color-pale);
  border: 1px solid var(--color-ink);
  border-radius: var(--radius);
  padding: 2rem;
  display: flex;
  align-items: center;
  gap: 1.5rem;
  flex-wrap: wrap;
}

.faq-cta__title {
  font-size: 1.1rem;
  font-weight: 700;
  margin-bottom: 0.35rem;
}

.faq-cta__desc {
  font-size: 0.9rem;
  color: var(--color-mid);
}

.faq-cta__inner .btn {
  flex-shrink: 0;
  margin-left: auto;
}

/* ===== 上下篇翻页 ===== */
.guide-pagination {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0.75rem;
  margin-top: 2.5rem;
  padding-top: 1.5rem;
  border-top: 1px solid var(--color-ink);
}

.pagination-link {
  display: flex;
  flex-direction: column;
  gap: 0.2rem;
  padding: 1rem;
  border: 1px solid var(--color-ink);
  border-radius: var(--radius);
  transition: background var(--transition);
}

.pagination-link:hover {
  background: var(--color-pale);
}

.pagination-link--next {
  text-align: right;
}

.pagination-dir {
  font-size: 0.72rem;
  color: var(--color-dim);
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.pagination-title {
  font-size: 0.88rem;
  font-weight: 600;
  line-height: 1.4;
}

.pagination-empty {
  display: block;
}

/* ===== 相关指南 ===== */
.related-guides {
  padding: 1.5rem 2rem;
  border-top: 2px solid var(--color-ink);
  max-width: 800px;
}

.related-guides__title {
  font-size: 0.78rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--color-dim);
  margin-bottom: 1rem;
}

.related-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
  gap: 0.5rem;
}

.related-card {
  border: 1px solid var(--color-ink);
  border-radius: var(--radius);
  border-bottom: 4px solid var(--color-ink);
  transition: transform var(--transition);
}

.related-card:hover { transform: translateY(-2px); }

.related-card__link {
  display: flex;
  align-items: flex-start;
  gap: 0.6rem;
  padding: 0.9rem;
  font-size: 0.84rem;
  line-height: 1.45;
}

.related-card__num {
  font-family: var(--font-mono);
  font-size: 0.68rem;
  color: var(--color-dim);
  flex-shrink: 0;
  padding-top: 2px;
}

.related-card__title {
  font-weight: 600;
}

@media (prefers-reduced-motion: no-preference) {
  .related-card {
    animation: fadeUp 0.45s ease both;
    animation-delay: calc(var(--stagger, 0) * 50ms);
  }
}

/* ===== FAQ 页指南列表 ===== */
.faq-guides-link {
  margin-top: 2.5rem;
  padding-top: 1.5rem;
  border-top: 1px solid var(--color-ink);
}

.faq-guides-link__title {
  font-size: 1rem;
  font-weight: 700;
  margin-bottom: 1rem;
}

.faq-guide-list {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
  gap: 0.5rem;
}

.faq-guide-item {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0.75rem 1rem;
  border: 1px solid var(--color-ink);
  border-radius: var(--radius);
  border-bottom: 4px solid var(--color-ink);
  font-size: 0.86rem;
  font-weight: 600;
  gap: 0.5rem;
  transition: background var(--transition);
}

.faq-guide-item:hover { background: var(--color-pale); }

.faq-guide-item__arrow {
  flex-shrink: 0;
  transition: transform var(--transition);
}

.faq-guide-item:hover .faq-guide-item__arrow {
  transform: translateX(3px);
}

/* ===== Changelog 页 ===== */
.changelog-cta {
  margin-top: 2.5rem;
  padding-top: 1.5rem;
  border-top: 1px solid var(--color-ink);
}

.changelog-cta__title {
  font-size: 1rem;
  font-weight: 700;
  margin-bottom: 1rem;
}

.changelog-cta__links {
  display: flex;
  gap: 0.75rem;
  flex-wrap: wrap;
}

/* ===== About 页 ===== */
.article-header--about { position: relative; }

.about-brand-block {
  margin-bottom: 0.75rem;
}

.about-brand-script {
  font-family: var(--font-script);
  font-size: 2rem;
  line-height: 1.2;
  display: block;
}

.about-links {
  margin-top: 2.5rem;
  padding-top: 1.5rem;
  border-top: 1px solid var(--color-ink);
}

.about-links__title {
  font-size: 1rem;
  font-weight: 700;
  margin-bottom: 1rem;
}

.about-link-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
  gap: 0.5rem;
}

.about-link-item {
  display: flex;
  align-items: flex-start;
  gap: 0.6rem;
  padding: 0.9rem 1rem;
  border: 1px solid var(--color-ink);
  border-radius: var(--radius);
  border-bottom: 4px solid var(--color-ink);
  transition: background var(--transition), transform var(--transition);
}

.about-link-item:hover {
  background: var(--color-pale);
  transform: translateY(-2px);
}

.about-link-item__num {
  font-family: var(--font-mono);
  font-size: 0.68rem;
  color: var(--color-dim);
  flex-shrink: 0;
  padding-top: 2px;
}

.about-link-item__title {
  font-size: 0.86rem;
  font-weight: 600;
  line-height: 1.4;
}

@media (prefers-reduced-motion: no-preference) {
  .about-link-item {
    animation: fadeUp 0.4s ease both;
    animation-delay: calc(var(--stagger, 0) * 55ms);
  }
}

/* ===== Privacy 页 ===== */
.privacy-bottom-nav {
  display: flex;
  gap: 0.75rem;
  margin-top: 2rem;
  padding-top: 1.5rem;
  border-top: 1px solid var(--color-ink);
  flex-wrap: wrap;
}

.prose--legal h2 { border-bottom: none; }

/* ===== 页脚 ===== */
.site-footer {
  border-top: 2px solid var(--color-ink);
  padding: 1.5rem 2rem;
  margin-top: auto;
}

.footer-nav {
  margin-bottom: 1rem;
}

.nav-dl--footer {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.25rem 0;
}

.nav-dl--footer .nav-dl__section {
  font-size: 0.68rem;
  letter-spacing: 0.12em;
  color: var(--color-dim);
  padding: 0;
  margin-right: 0.75rem;
}

.nav-dl--footer dd {
  display: inline;
}

.footer-link {
  font-size: 0.82rem;
  color: var(--color-mid);
  padding: 0.2rem 0.5rem;
  min-height: 40px;
  display: inline-flex;
  align-items: center;
  transition: color var(--transition);
}

.footer-link:hover { color: var(--color-ink); }

.footer-copy {
  font-size: 0.78rem;
  color: var(--color-dim);
  text-align: center;
  letter-spacing: 0.02em;
}

/* ===== Prose 内 changelog 样式 ===== */
.prose--changelog h2 {
  font-family: var(--font-mono);
  font-size: 1rem;
  letter-spacing: 0.08em;
}

/* ===== 响应式 ===== */
@media (max-width: 768px) {
  :root {
    --sidebar-w: 0px;
  }

  .sidebar {
    transform: translateX(-260px);
    width: 260px;
  }

  .sidebar.is-open {
    transform: translateX(0);
  }

  .nav-overlay {
    display: block;
  }

  .nav-overlay.is-visible {
    opacity: 1;
    pointer-events: auto;
  }

  .nav-toggle {
    display: flex;
  }

  .main-content {
    margin-left: 0;
  }

  .hero {
    min-height: 52vh;
  }

  .hero__body {
    padding: 2rem 1.25rem 4.5rem;
  }

  .hero__h1 {
    font-size: 1.55rem;
  }

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

  .guide-header {
    padding: 0.75rem 1.25rem;
  }

  .page-article {
    padding: 1.25rem;
  }

  .related-guides {
    padding: 1.25rem;
  }

  .guide-pagination {
    grid-template-columns: 1fr;
  }

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

  .faq-cta__inner {
    flex-direction: column;
    align-items: flex-start;
  }

  .faq-cta__inner .btn {
    margin-left: 0;
  }

  .site-footer {
    padding: 1.25rem;
  }

  .nav-dl--footer {
    flex-direction: column;
    align-items: flex-start;
    gap: 0;
  }

  .footer-link {
    padding: 0.4rem 0;
  }
}

@media (max-width: 480px) {
  html { font-size: 16px; }

  .about-link-grid,
  .faq-guide-list {
    grid-template-columns: 1fr;
  }

  .hero__actions {
    flex-direction: column;
  }

  .btn {
    width: 100%;
    justify-content: center;
  }

  .changelog-cta__links {
    flex-direction: column;
  }

  .privacy-bottom-nav {
    flex-direction: column;
  }
}

/* ===== 减少动效 ===== */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    transition-duration: 0.01ms !important;
  }
}