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

/* ===== 变量与重置 ===== */
:root {
  --c-base: #c8e0f4;
  --c-accent: #f5e0e8;
  --c-dark: #171f26;
  --c-base-light: #ddeef8;
  --c-base-dark: #aecde8;
  --c-accent-dark: #e8c8d8;
  --c-text: #171f26;
  --c-text-muted: #4a5568;
  --c-text-light: #6b7a8d;
  --c-surface: #d4e6f5;
  --c-surface-raised: #dceef8;

  --shadow-raise: -4px -4px 12px rgba(255,255,255,0.75), 5px 5px 14px rgba(23,31,38,0.13);
  --shadow-inset: inset 3px 3px 8px rgba(23,31,38,0.11), inset -3px -3px 8px rgba(255,255,255,0.7);
  --shadow-card: -3px -3px 10px rgba(255,255,255,0.7), 4px 4px 12px rgba(23,31,38,0.12);
  --shadow-btn: -2px -2px 8px rgba(255,255,255,0.8), 3px 3px 8px rgba(23,31,38,0.15);

  --radius: 14px;
  --radius-sm: 10px;
  --font: 'DM Sans', system-ui, -apple-system, sans-serif;
  --max-w: 1100px;
  --transition: 150ms ease;
}

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

html {
  font-size: 17px;
  line-height: 1.65;
  color: var(--c-text);
  background-color: var(--c-base);
  font-family: var(--font);
  scroll-behavior: smooth;
}

body {
  min-height: 100vh;
  background: linear-gradient(145deg, var(--c-base-light) 0%, var(--c-base) 60%, var(--c-base-dark) 100%);
  display: flex;
  flex-direction: column;
}

main { flex: 1; }

img { max-width: 100%; height: auto; display: block; }
a { color: var(--c-dark); text-decoration: none; }
a:hover { color: #2d4a6b; }
ol, ul { list-style: none; }

/* ===== 顶部公告条 ===== */
.header-announce {
  background: linear-gradient(90deg, var(--c-dark) 0%, #243040 100%);
  color: var(--c-base-light);
  font-size: 0.78rem;
  text-align: center;
  padding: 6px 16px;
  letter-spacing: 0.04em;
  font-weight: 500;
}

/* ===== 站点头部 / 品牌 ===== */
.site-header {
  background: var(--c-base);
  position: sticky;
  top: 0;
  z-index: 100;
  box-shadow: 0 2px 16px rgba(23,31,38,0.10);
}

.header-brand {
  text-align: center;
  padding: 14px 16px 4px;
  border-bottom: 1px solid rgba(23,31,38,0.07);
}

.brand-link {
  font-size: 1.35rem;
  font-weight: 700;
  color: var(--c-dark);
  letter-spacing: 0.02em;
  display: inline-block;
}

.brand-link:hover { color: #2a4a70; }

/* ===== 导航 nav > ol > li > a ===== */
.site-nav {
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
  scrollbar-width: none;
}

.site-nav::-webkit-scrollbar { display: none; }

.site-nav ol {
  display: flex;
  flex-wrap: nowrap;
  gap: 2px;
  padding: 6px 12px;
  justify-content: center;
}

.site-nav ol li a {
  display: flex;
  align-items: center;
  padding: 8px 14px;
  border-radius: var(--radius-sm);
  font-size: 0.85rem;
  font-weight: 500;
  color: var(--c-text-muted);
  white-space: nowrap;
  min-height: 40px;
  transition: background var(--transition), color var(--transition), box-shadow var(--transition);
  background: transparent;
}

.site-nav ol li a:hover,
.site-nav ol li a.active {
  background: linear-gradient(145deg, var(--c-base-light), var(--c-base-dark));
  box-shadow: var(--shadow-raise);
  color: var(--c-dark);
}

.site-nav ol li.active a,
.site-nav ol li a[class*="active"] {
  background: linear-gradient(145deg, var(--c-base-light), var(--c-base-dark));
  box-shadow: var(--shadow-raise);
  color: var(--c-dark);
}

/* ===== 面包屑 ===== */
.breadcrumb-bar {
  background: linear-gradient(145deg, var(--c-base-light), var(--c-base));
  border-bottom: 1px solid rgba(23,31,38,0.07);
  padding: 6px 0;
}

.breadcrumb {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 0 20px;
  display: flex;
  flex-wrap: wrap;
  gap: 4px;
  align-items: center;
  font-size: 0.8rem;
  color: var(--c-text-light);
}

.breadcrumb li + li::before { content: '›'; margin-right: 4px; color: var(--c-text-light); }
.breadcrumb li a { color: var(--c-text-muted); }
.breadcrumb li a:hover { color: var(--c-dark); }
.breadcrumb li.bc-current { color: var(--c-dark); font-weight: 500; }

/* ===== Eyebrow 标题条 ===== */
.page-eyebrow-bar {
  background: linear-gradient(145deg, var(--c-base), var(--c-base-dark));
  border-bottom: 2px solid rgba(23,31,38,0.08);
  padding: 20px 0 16px;
}

.eyebrow-inner {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 0 20px;
  display: flex;
  align-items: center;
  gap: 14px;
}

.eyebrow-tag {
  display: inline-block;
  background: linear-gradient(145deg, var(--c-accent), var(--c-accent-dark));
  box-shadow: var(--shadow-btn);
  color: var(--c-dark);
  font-size: 0.75rem;
  font-weight: 700;
  padding: 5px 12px;
  border-radius: 20px;
  letter-spacing: 0.06em;
}

.eyebrow-title {
  font-size: 1rem;
  font-weight: 600;
  color: var(--c-text-muted);
}

/* ===== Hero ===== */
.hero-section {
  position: relative;
  min-height: 45vh;
  background: linear-gradient(160deg, var(--c-dark) 0%, #243040 55%, #1a2d42 100%);
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
  padding: 48px 20px 80px;
}

.hero-content {
  text-align: center;
  position: relative;
  z-index: 2;
  max-width: 680px;
}

.hero-h1 {
  font-size: clamp(1.6rem, 4vw, 2.6rem);
  font-weight: 700;
  color: var(--c-base-light);
  line-height: 1.3;
  margin-bottom: 16px;
  text-shadow: 0 2px 12px rgba(0,0,0,0.3);
}

.hero-sub {
  font-size: 1rem;
  color: rgba(200,224,244,0.80);
  margin-bottom: 28px;
  line-height: 1.7;
}

.hero-btn {
  display: inline-block;
  background: linear-gradient(145deg, var(--c-accent), var(--c-accent-dark));
  box-shadow: var(--shadow-btn);
  color: var(--c-dark);
  font-weight: 700;
  font-size: 0.95rem;
  padding: 13px 30px;
  border-radius: var(--radius);
  transition: box-shadow var(--transition), transform var(--transition);
  min-height: 48px;
  line-height: 1.4;
}

.hero-btn:hover {
  box-shadow: -4px -4px 14px rgba(255,255,255,0.9), 6px 6px 16px rgba(23,31,38,0.2);
  transform: translateY(-1px);
  color: var(--c-dark);
}

.hero-btn:active {
  transform: scale(0.97);
  box-shadow: var(--shadow-inset);
}

.hero-arc {
  position: absolute;
  bottom: -2px;
  left: -5%;
  width: 110%;
  height: 60px;
  background: var(--c-base);
  border-radius: 50% 50% 0 0 / 100% 100% 0 0;
  z-index: 3;
}

/* ===== 内容容器 main > article > div > div ===== */
.content-wrap {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 36px 20px 48px;
}

.content-inner {
  background: linear-gradient(145deg, var(--c-base-light), var(--c-surface));
  border-radius: var(--radius);
  box-shadow: var(--shadow-card);
  padding: 36px 40px;
}

/* ===== 页面 H1 ===== */
.page-h1 {
  font-size: clamp(1.4rem, 3vw, 2rem);
  font-weight: 700;
  color: var(--c-dark);
  line-height: 1.3;
  margin-bottom: 24px;
  padding-bottom: 16px;
  border-bottom: 2px solid var(--c-base-dark);
}

/* ===== 文章 meta 日期 ===== */
.article-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 16px;
  margin-bottom: 24px;
  padding: 10px 16px;
  background: linear-gradient(145deg, var(--c-base), var(--c-base-dark));
  border-radius: var(--radius-sm);
  box-shadow: var(--shadow-inset);
}

.meta-date {
  font-size: 0.82rem;
  color: var(--c-text-muted);
  font-weight: 500;
}

/* ===== 正文排版 ===== */
.content-inner h2 {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--c-dark);
  margin: 32px 0 14px;
  padding-left: 12px;
  border-left: 3px solid var(--c-accent-dark);
}

.content-inner h3 {
  font-size: 1.05rem;
  font-weight: 600;
  color: var(--c-dark);
  margin: 24px 0 10px;
}

.content-inner p {
  margin-bottom: 16px;
  color: var(--c-text);
  line-height: 1.75;
}

.content-inner ul,
.content-inner ol {
  margin: 0 0 18px 20px;
  list-style: disc;
}

.content-inner ol { list-style: decimal; }

.content-inner li {
  margin-bottom: 8px;
  line-height: 1.7;
}

.content-inner a {
  color: #2a6496;
  text-decoration: underline;
  text-underline-offset: 3px;
}

.content-inner a:hover { color: #1a3d5e; }

.content-inner table {
  width: 100%;
  border-collapse: collapse;
  margin-bottom: 20px;
  font-size: 0.9rem;
  border-radius: var(--radius-sm);
  overflow: hidden;
  box-shadow: var(--shadow-card);
}

.content-inner th,
.content-inner td {
  padding: 10px 14px;
  text-align: left;
  border-bottom: 1px solid rgba(23,31,38,0.08);
}

.content-inner th {
  background: var(--c-base-dark);
  font-weight: 700;
  color: var(--c-dark);
}

.content-inner tr:last-child td { border-bottom: none; }

.content-inner blockquote {
  margin: 20px 0;
  padding: 14px 20px;
  background: linear-gradient(145deg, var(--c-base), var(--c-base-dark));
  border-radius: var(--radius-sm);
  box-shadow: var(--shadow-inset);
  color: var(--c-text-muted);
  font-style: italic;
}

/* ===== 首页卡片网格 ===== */
.home-cards {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 0 20px 48px;
}

.section-header {
  margin-bottom: 20px;
  display: flex;
  align-items: center;
  gap: 12px;
}

.section-label {
  font-size: 0.85rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  color: var(--c-text-muted);
  text-transform: uppercase;
  padding: 6px 14px;
  background: linear-gradient(145deg, var(--c-base-light), var(--c-base-dark));
  border-radius: 20px;
  box-shadow: var(--shadow-btn);
}

.cards-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 20px;
  list-style: none;
}

.card-item { list-style: none; }

.card-link {
  display: block;
  background: linear-gradient(145deg, var(--c-base-light), var(--c-surface));
  border-radius: var(--radius);
  box-shadow: var(--shadow-card);
  padding: 24px;
  transition: box-shadow var(--transition), transform var(--transition);
  height: 100%;
  color: var(--c-text);
}

.card-link:hover {
  box-shadow: -6px -6px 18px rgba(255,255,255,0.85), 7px 7px 18px rgba(23,31,38,0.16);
  transform: translateY(-2px);
  color: var(--c-dark);
}

.card-link:active {
  transform: scale(0.98);
  box-shadow: var(--shadow-inset);
}

.card-body { display: flex; flex-direction: column; gap: 8px; }

.card-title {
  font-size: 1rem;
  font-weight: 700;
  color: var(--c-dark);
  line-height: 1.4;
}

.card-date {
  font-size: 0.78rem;
  color: var(--c-text-light);
}

.card-desc {
  font-size: 0.87rem;
  color: var(--c-text-muted);
  line-height: 1.6;
  margin: 0;
}

.card-more {
  font-size: 0.82rem;
  font-weight: 600;
  color: var(--c-text-muted);
  margin-top: 8px;
  display: inline-block;
  transition: color var(--transition);
}

.card-link:hover .card-more { color: var(--c-dark); }

/* ===== 排行榜 ===== */
.ranking-list {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 0 20px 48px;
}

.rank-ol {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.rank-item {
  display: flex;
  align-items: center;
  gap: 16px;
  background: linear-gradient(145deg, var(--c-base-light), var(--c-surface));
  border-radius: var(--radius);
  box-shadow: var(--shadow-card);
  padding: 16px 20px;
  transition: box-shadow var(--transition), transform var(--transition);
}

.rank-item:hover {
  box-shadow: -5px -5px 16px rgba(255,255,255,0.85), 6px 6px 16px rgba(23,31,38,0.15);
  transform: translateX(3px);
}

.rank-num {
  font-size: 1.4rem;
  font-weight: 700;
  color: var(--c-base-dark);
  min-width: 42px;
  text-align: center;
  font-variant-numeric: tabular-nums;
  background: linear-gradient(145deg, var(--c-base), var(--c-base-dark));
  border-radius: var(--radius-sm);
  box-shadow: var(--shadow-inset);
  padding: 6px;
  line-height: 1;
}

.rank-item:nth-child(1) .rank-num { color: #b8860b; }
.rank-item:nth-child(2) .rank-num { color: #6e6e6e; }
.rank-item:nth-child(3) .rank-num { color: #8b4513; }

.rank-link {
  flex: 1;
  display: flex;
  flex-direction: column;
  gap: 4px;
  color: var(--c-text);
}

.rank-title {
  font-size: 0.97rem;
  font-weight: 600;
  color: var(--c-dark);
}

.rank-desc, .rank-date {
  font-size: 0.8rem;
  color: var(--c-text-muted);
}

.rank-arrow {
  font-size: 1.1rem;
  color: var(--c-text-light);
  transition: transform var(--transition);
}

.rank-item:hover .rank-arrow { transform: translateX(4px); }

/* ===== 双栏布局（对比/FAQ/Review） ===== */
.compare-layout,
.faq-layout,
.review-layout {
  display: grid;
  grid-template-columns: 1fr 300px;
  gap: 28px;
  align-items: start;
}

.compare-aside,
.faq-aside,
.review-aside {
  display: flex;
  flex-direction: column;
  gap: 18px;
  position: sticky;
  top: 120px;
}

.aside-block {
  background: linear-gradient(145deg, var(--c-base-light), var(--c-surface));
  border-radius: var(--radius);
  box-shadow: var(--shadow-card);
  padding: 20px 22px;
}

.aside-tip {
  background: linear-gradient(145deg, var(--c-accent), var(--c-accent-dark));
}

.aside-label {
  display: block;
  font-size: 0.78rem;
  font-weight: 700;
  letter-spacing: 0.07em;
  color: var(--c-text-muted);
  margin-bottom: 12px;
  text-transform: uppercase;
}

.aside-links {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.aside-links li a {
  font-size: 0.87rem;
  color: var(--c-text-muted);
  font-weight: 500;
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 6px 0;
  min-height: 40px;
  transition: color var(--transition);
}

.aside-links li a::before {
  content: '›';
  color: var(--c-base-dark);
}

.aside-links li a:hover { color: var(--c-dark); }

.aside-tip p {
  font-size: 0.85rem;
  color: var(--c-text-muted);
  line-height: 1.65;
  margin: 0;
}

/* ===== 子页列表 ol > li > a + small ===== */
.child-pages {
  margin-top: 36px;
  padding-top: 28px;
  border-top: 2px solid var(--c-base-dark);
}

.child-ol {
  display: flex;
  flex-direction: column;
  gap: 12px;
  margin-top: 16px;
}

.child-ol li {
  display: flex;
  flex-direction: column;
  background: linear-gradient(145deg, var(--c-base), var(--c-base-dark));
  border-radius: var(--radius-sm);
  box-shadow: var(--shadow-btn);
  padding: 14px 18px;
  transition: box-shadow var(--transition), transform var(--transition);
}

.child-ol li:hover {
  box-shadow: var(--shadow-raise);
  transform: translateX(2px);
}

.child-ol li a {
  font-size: 0.95rem;
  font-weight: 600;
  color: var(--c-dark);
  margin-bottom: 4px;
}

.child-ol li small {
  font-size: 0.8rem;
  color: var(--c-text-muted);
  line-height: 1.5;
}

/* ===== 同栏目导航 ===== */
.sibling-nav {
  background: linear-gradient(145deg, var(--c-base-light), var(--c-surface));
  border-radius: var(--radius);
  box-shadow: var(--shadow-card);
  padding: 20px 22px;
}

.sibling-nav .aside-label {
  display: block;
  font-size: 0.78rem;
  font-weight: 700;
  letter-spacing: 0.07em;
  color: var(--c-text-muted);
  margin-bottom: 12px;
}

.sibling-nav ol {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.sibling-nav ol li a {
  font-size: 0.87rem;
  color: var(--c-text-muted);
  font-weight: 500;
  display: flex;
  align-items: flex-start;
  gap: 6px;
  padding: 4px 0;
  min-height: 40px;
  line-height: 1.4;
}

.sibling-nav ol li a::before {
  content: '›';
  color: var(--c-base-dark);
  flex-shrink: 0;
  margin-top: 1px;
}

.sibling-nav ol li a:hover { color: var(--c-dark); }
.sibling-nav ol li small {
  display: block;
  font-size: 0.75rem;
  color: var(--c-text-light);
}

/* ===== About 相关按钮 ===== */
.about-nav-links {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 32px;
  padding-top: 24px;
  border-top: 2px solid var(--c-base-dark);
}

.about-link-btn {
  display: inline-flex;
  align-items: center;
  min-height: 44px;
  padding: 10px 22px;
  background: linear-gradient(145deg, var(--c-base-light), var(--c-base-dark));
  border-radius: var(--radius-sm);
  box-shadow: var(--shadow-btn);
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--c-dark);
  transition: box-shadow var(--transition), transform var(--transition);
}

.about-link-btn:hover {
  box-shadow: var(--shadow-raise);
  transform: translateY(-1px);
  color: var(--c-dark);
}

.about-link-btn:active {
  box-shadow: var(--shadow-inset);
  transform: scale(0.97);
}

/* ===== Privacy 底部链接 ===== */
.privacy-bottom-links {
  display: flex;
  gap: 16px;
  margin-top: 28px;
  padding-top: 20px;
  border-top: 1px solid var(--c-base-dark);
}

.privacy-bottom-links a {
  font-size: 0.87rem;
  color: var(--c-text-muted);
  font-weight: 500;
  min-height: 40px;
  display: inline-flex;
  align-items: center;
}

.privacy-bottom-links a:hover { color: var(--c-dark); }

/* ===== 页脚 ===== */
.site-footer {
  margin-top: auto;
  background: linear-gradient(145deg, var(--c-dark) 0%, #1e2932 100%);
  padding: 20px 0;
}

.footer-inner {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 0 20px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 12px;
}

.footer-brand {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--c-base-light);
  letter-spacing: 0.01em;
}

.footer-links {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 16px;
}

.footer-copy {
  font-size: 0.8rem;
  color: rgba(200,224,244,0.5);
}

.footer-links a {
  font-size: 0.85rem;
  color: rgba(200,224,244,0.7);
  font-weight: 500;
  min-height: 40px;
  display: inline-flex;
  align-items: center;
  transition: color var(--transition);
}

.footer-links a:hover { color: var(--c-base-light); }

/* ===== FAQ 内容 (dl 样式) ===== */
.faq-content dl { margin: 0; }

.faq-content dt {
  font-size: 1rem;
  font-weight: 700;
  color: var(--c-dark);
  padding: 14px 18px;
  margin-top: 16px;
  background: linear-gradient(145deg, var(--c-base), var(--c-base-dark));
  border-radius: var(--radius-sm) var(--radius-sm) 0 0;
  box-shadow: var(--shadow-btn);
  cursor: pointer;
}

.faq-content dd {
  font-size: 0.93rem;
  color: var(--c-text-muted);
  line-height: 1.75;
  padding: 14px 18px 16px;
  background: linear-gradient(145deg, var(--c-surface-raised), var(--c-surface));
  border-radius: 0 0 var(--radius-sm) var(--radius-sm);
  margin-left: 0;
  box-shadow: var(--shadow-inset);
}

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

/* ===== 响应式 ===== */
@media (max-width: 860px) {
  .compare-layout,
  .faq-layout,
  .review-layout {
    grid-template-columns: 1fr;
  }

  .compare-aside,
  .faq-aside,
  .review-aside {
    position: static;
  }

  .cards-grid {
    grid-template-columns: repeat(auto-fill, minmax(240px, 1fr));
  }
}

@media (max-width: 600px) {
  html { font-size: 16px; }

  .header-brand { padding: 10px 12px 4px; }
  .brand-link { font-size: 1.1rem; }

  .site-nav ol { justify-content: flex-start; padding: 6px 8px; }
  .site-nav ol li a { padding: 8px 10px; font-size: 0.8rem; }

  .hero-section { min-height: 40vh; padding: 36px 16px 70px; }
  .hero-h1 { font-size: 1.4rem; }
  .hero-arc { height: 40px; }

  .content-wrap { padding: 20px 12px 32px; }
  .content-inner { padding: 22px 18px; }

  .eyebrow-inner { flex-direction: column; align-items: flex-start; gap: 8px; }

  .footer-inner { flex-direction: column; align-items: flex-start; }
  .footer-brand { font-size: 1.2rem; }

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

  .rank-item { flex-wrap: wrap; }

  .about-nav-links { flex-direction: column; }
  .about-link-btn { width: 100%; justify-content: center; }

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

  .privacy-wrap .content-inner,
  .compare-layout .content-inner { padding: 20px 16px; }
}

@media (max-width: 400px) {
  .site-nav ol li a { padding: 8px 8px; font-size: 0.77rem; }
  .content-inner { padding: 18px 14px; }
}