:root {
  --primary: #f76b8a;
  --primary-dark: #e04f70;
  --primary-soft: #fff0f4;
  --secondary: #6bb8f7;
  --secondary-soft: #f0f8ff;
  --accent: #ffb347;
  --text: #2d2d2d;
  --text-soft: #555;
  --text-muted: #888;
  --bg: #ffffff;
  --bg-soft: #fafafa;
  --bg-card: rgba(255, 255, 255, 0.72);
  --border: #eeeeee;
  --border-glass: rgba(255, 255, 255, 0.6);
  --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.06);
  --shadow-md: 0 8px 24px rgba(247, 107, 138, 0.12);
  --shadow-lg: 0 16px 48px rgba(247, 107, 138, 0.18);
  --radius-sm: 10px;
  --radius: 16px;
  --radius-lg: 24px;
  --gradient-hero: linear-gradient(135deg, #fff0f4 0%, #f0f8ff 55%, #fff8ec 100%);
  --gradient-primary: linear-gradient(135deg, #f76b8a 0%, #ff9a8b 100%);
  --transition: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

@media (prefers-color-scheme: dark) {
  :root {
    --primary: #ff8aa3;
    --primary-dark: #f76b8a;
    --primary-soft: rgba(247, 107, 138, 0.14);
    --secondary: #7cc0f7;
    --secondary-soft: rgba(107, 184, 247, 0.12);
    --text: #ececec;
    --text-soft: #c2c2c2;
    --text-muted: #8f8f8f;
    --bg: #16161a;
    --bg-soft: #1e1e24;
    --bg-card: rgba(38, 38, 46, 0.62);
    --border: #2c2c34;
    --border-glass: rgba(255, 255, 255, 0.08);
    --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.4);
    --shadow-md: 0 8px 24px rgba(0, 0, 0, 0.45);
    --shadow-lg: 0 16px 48px rgba(0, 0, 0, 0.55);
    --gradient-hero: linear-gradient(135deg, rgba(247, 107, 138, 0.16) 0%, rgba(107, 184, 247, 0.12) 55%, rgba(255, 179, 71, 0.1) 100%);
  }
}

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

html {
  scroll-behavior: smooth;
  scroll-padding-top: 80px;
}

body {
  font-family: "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", system-ui, -apple-system, sans-serif;
  color: var(--text);
  background: var(--bg);
  line-height: 1.8;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
  transition: background var(--transition), color var(--transition);
}

a {
  color: var(--primary);
  text-decoration: none;
  transition: color var(--transition), opacity var(--transition);
}

a:hover {
  color: var(--primary-dark);
  text-decoration: underline;
}

header {
  position: sticky;
  top: 0;
  background: var(--bg-card);
  -webkit-backdrop-filter: saturate(180%) blur(18px);
  backdrop-filter: saturate(180%) blur(18px);
  border-bottom: 1px solid var(--border-glass);
  box-shadow: var(--shadow-sm);
  z-index: 100;
  transition: background var(--transition), box-shadow var(--transition);
}

.nav {
  max-width: 1200px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 12px 20px;
  gap: 16px;
}

.logo {
  font-size: 22px;
  font-weight: 700;
  letter-spacing: 0.5px;
  background: var(--gradient-primary);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  color: transparent;
  transition: transform var(--transition), filter var(--transition);
}

.logo:hover {
  text-decoration: none;
  transform: translateY(-1px);
  filter: brightness(1.08);
}

.nav-links {
  display: flex;
  gap: 24px;
  list-style: none;
  align-items: center;
}

.nav-links a {
  position: relative;
  color: var(--text-soft);
  font-size: 15px;
  padding: 4px 0;
  transition: color var(--transition);
}

.nav-links a::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: -2px;
  width: 0;
  height: 2px;
  border-radius: 2px;
  background: var(--gradient-primary);
  transition: width var(--transition);
}

.nav-links a:hover {
  color: var(--primary);
  text-decoration: none;
}

.nav-links a:hover::after {
  width: 100%;
}

.menu-toggle {
  display: none;
  background: var(--primary-soft);
  border: none;
  color: var(--primary);
  font-size: 22px;
  line-height: 1;
  padding: 6px 12px;
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: background var(--transition), transform var(--transition);
}

.menu-toggle:hover {
  background: var(--primary);
  color: #fff;
  transform: scale(1.05);
}

main {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 20px;
}

.breadcrumb {
  font-size: 13px;
  color: var(--text-muted);
  padding: 16px 0;
}

.breadcrumb a {
  color: var(--text-muted);
}

.breadcrumb a:hover {
  color: var(--primary);
}

.hero {
  position: relative;
  overflow: hidden;
  background: var(--gradient-hero);
  border: 1px solid var(--border-glass);
  border-radius: var(--radius-lg);
  padding: 48px 32px;
  margin-bottom: 32px;
  box-shadow: var(--shadow-md);
  animation: fadeUp 0.7s var(--transition) both;
}

.hero::before {
  content: "";
  position: absolute;
  top: -120px;
  right: -120px;
  width: 320px;
  height: 320px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(247, 107, 138, 0.22), transparent 70%);
  pointer-events: none;
}

.hero::after {
  content: "";
  position: absolute;
  bottom: -140px;
  left: -80px;
  width: 280px;
  height: 280px;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(107, 184, 247, 0.2), transparent 70%);
  pointer-events: none;
}

.hero h1 {
  position: relative;
  font-size: 32px;
  line-height: 1.4;
  color: var(--text);
  margin-bottom: 16px;
  animation: fadeUp 0.7s 0.1s var(--transition) both;
}

.hero p {
  position: relative;
  font-size: 16px;
  color: var(--text-soft);
  max-width: 800px;
  animation: fadeUp 0.7s 0.2s var(--transition) both;
}

.section {
  margin-bottom: 48px;
  animation: fadeUp 0.6s var(--transition) both;
}

.section h2 {
  position: relative;
  font-size: 24px;
  color: var(--text);
  margin-bottom: 16px;
  padding-left: 14px;
  border-left: 4px solid var(--primary);
  line-height: 1.4;
}

.section h2::after {
  content: "";
  position: absolute;
  left: -4px;
  bottom: 0;
  width: 4px;
  height: 40%;
  border-radius: 4px;
  background: var(--secondary);
}

.section h3 {
  font-size: 18px;
  color: var(--text);
  margin: 20px 0 10px;
}

.section h4 {
  font-size: 16px;
  color: var(--text-soft);
  margin: 14px 0 8px;
}

.section p {
  font-size: 15px;
  color: var(--text-soft);
  margin-bottom: 12px;
  text-align: justify;
}

.grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 20px;
}

.card {
  position: relative;
  background: var(--bg-card);
  -webkit-backdrop-filter: blur(12px);
  backdrop-filter: blur(12px);
  border-radius: var(--radius);
  padding: 20px;
  border: 1px solid var(--border-glass);
  box-shadow: var(--shadow-sm);
  transition: transform var(--transition), box-shadow var(--transition), border-color var(--transition);
  overflow: hidden;
}

.card::before {
  content: "";
  position: absolute;
  inset: 0;
  border-radius: inherit;
  padding: 1px;
  background: linear-gradient(135deg, rgba(247, 107, 138, 0.5), transparent 40%, rgba(107, 184, 247, 0.4));
  -webkit-mask: linear-gradient(#fff 0 0) content-box, linear-gradient(#fff 0 0);
  -webkit-mask-composite: xor;
  mask-composite: exclude;
  opacity: 0;
  transition: opacity var(--transition);
  pointer-events: none;
}

.card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-lg);
}

.card:hover::before {
  opacity: 1;
}

.card h3 {
  font-size: 17px;
  margin-bottom: 8px;
  color: var(--primary);
}

.card p {
  font-size: 14px;
  color: var(--text-soft);
  margin-bottom: 0;
}

.stats {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(160px, 1fr));
  gap: 16px;
  margin: 24px 0 0;
  position: relative;
}

.stat {
  text-align: center;
  background: var(--bg-card);
  -webkit-backdrop-filter: blur(10px);
  backdrop-filter: blur(10px);
  border: 1px solid var(--border-glass);
  border-radius: var(--radius);
  padding: 20px 12px;
  transition: transform var(--transition), box-shadow var(--transition);
}

.stat:hover {
  transform: translateY(-4px) scale(1.02);
  box-shadow: var(--shadow-md);
}

.stat .num {
  font-size: 28px;
  font-weight: 700;
  background: var(--gradient-primary);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  color: transparent;
  line-height: 1.3;
}

.stat .label {
  font-size: 13px;
  color: var(--text-muted);
  margin-top: 4px;
}

.faq-item {
  border-bottom: 1px solid var(--border);
  padding: 16px 0;
  transition: background var(--transition);
}

.faq-item summary {
  cursor: pointer;
  font-weight: 600;
  font-size: 15px;
  color: var(--text);
  list-style: none;
  padding: 4px 8px;
  border-radius: var(--radius-sm);
  transition: background var(--transition), color var(--transition);
}

.faq-item summary:hover {
  background: var(--primary-soft);
  color: var(--primary);
}

.faq-item summary::-webkit-details-marker {
  display: none;
}

.faq-item summary::before {
  content: "＋";
  display: inline-block;
  color: var(--primary);
  margin-right: 8px;
  font-weight: 700;
  transition: transform var(--transition);
}

.faq-item[open] summary::before {
  content: "－";
}

.faq-item p {
  margin-top: 10px;
  padding: 0 8px;
  font-size: 14px;
  color: var(--text-soft);
  animation: fadeUp 0.35s var(--transition) both;
}

.article-list {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 20px;
}

.article-item {
  position: relative;
  background: var(--bg-card);
  -webkit-backdrop-filter: blur(12px);
  backdrop-filter: blur(12px);
  border: 1px solid var(--border-glass);
  border-radius: var(--radius);
  padding: 20px;
  box-shadow: var(--shadow-sm);
  transition: transform var(--transition), box-shadow var(--transition);
}

.article-item:hover {
  transform: translateY(-5px);
  box-shadow: var(--shadow-lg);
}

.article-item h3 {
  font-size: 16px;
  color: var(--text);
  margin-bottom: 8px;
  transition: color var(--transition);
}

.article-item:hover h3 {
  color: var(--primary);
}

.article-item .meta {
  font-size: 12px;
  color: var(--text-muted);
  margin-bottom: 8px;
}

.article-item p {
  font-size: 14px;
  color: var(--text-soft);
  margin-bottom: 10px;
}

.article-item a {
  font-size: 13px;
  color: var(--primary);
  font-weight: 600;
  display: inline-flex;
  align-items: center;
  gap: 4px;
}

.article-item a::after {
  content: "→";
  transition: transform var(--transition);
}

.article-item a:hover::after {
  transform: translateX(4px);
}

.contact-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 16px;
}

.contact-item {
  background: var(--bg-card);
  -webkit-backdrop-filter: blur(10px);
  backdrop-filter: blur(10px);
  border: 1px solid var(--border-glass);
  border-radius: var(--radius-sm);
  padding: 16px;
  transition: transform var(--transition), box-shadow var(--transition), border-color var(--transition);
}

.contact-item:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-md);
  border-color: var(--primary);
}

.contact-item strong {
  display: block;
  color: var(--primary);
  margin-bottom: 4px;
  font-size: 14px;
}

.contact-item span {
  font-size: 14px;
  color: var(--text-soft);
  word-break: break-all;
}

footer {
  background: var(--bg-soft);
  color: var(--text-muted);
  padding: 40px 20px;
  margin-top: 48px;
  font-size: 13px;
  border-top: 1px solid var(--border);
}

.footer-inner {
  max-width: 1200px;
  margin: 0 auto;
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 24px;
}

footer h4 {
  color: var(--text);
  margin-bottom: 10px;
  font-size: 14px;
}

footer p {
  color: var(--text-muted);
  margin-bottom: 6px;
  line-height: 1.7;
}

footer a {
  color: var(--text-muted);
  display: block;
  margin-bottom: 6px;
  transition: color var(--transition), transform var(--transition);
}

footer a:hover {
  color: var(--primary);
  transform: translateX(3px);
  text-decoration: none;
}

.copyright {
  max-width: 1200px;
  margin: 24px auto 0;
  padding-top: 20px;
  border-top: 1px solid var(--border);
  text-align: center;
  font-size: 12px;
  color: var(--text-muted);
}

.back-top {
  position: fixed;
  right: 24px;
  bottom: 24px;
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background: var(--gradient-primary);
  color: #fff;
  border: none;
  font-size: 20px;
  cursor: pointer;
  display: none;
  z-index: 99;
  box-shadow: var(--shadow-md);
  transition: transform var(--transition), box-shadow var(--transition), filter var(--transition);
}

.back-top:hover {
  transform: translateY(-4px) scale(1.08);
  box-shadow: var(--shadow-lg);
  filter: brightness(1.08);
}

.back-top:active {
  transform: scale(0.95);
}

@keyframes fadeUp {
  from {
    opacity: 0;
    transform: translateY(20px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
}

@media (max-width: 768px) {
  .nav-links {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background: var(--bg-card);
    -webkit-backdrop-filter: blur(18px);
    backdrop-filter: blur(18px);
    flex-direction: column;
    align-items: flex-start;
    padding: 16px 20px;
    gap: 14px;
    box-shadow: var(--shadow-md);
    border-bottom: 1px solid var(--border-glass);
  }

  .nav-links.open {
    display: flex;
    animation: fadeUp 0.3s var(--transition) both;
  }

  .menu-toggle {
    display: block;
  }

  .hero {
    padding: 32px 20px;
    border-radius: var(--radius);
  }

  .hero h1 {
    font-size: 24px;
  }

  .hero p {
    font-size: 15px;
  }

  .section h2 {
    font-size: 20px;
  }

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

  .back-top {
    right: 16px;
    bottom: 16px;
  }
}

@media (max-width: 480px) {
  .hero h1 {
    font-size: 21px;
  }

  .stat .num {
    font-size: 24px;
  }

  .grid,
  .article-list,
  .contact-grid {
    grid-template-columns: 1fr;
  }
}