:root {
  --bg-body: #F8FAFC;
  --bg-card: #FFFFFF;
  --bg-header: #0B2B4A;
  --bg-footer: #0F1E2E;
  --bg-soft: #EEF2F7;
  --text-primary: #17202A;
  --text-heading: #0A1C2E;
  --text-secondary: #334155;
  --text-muted: #475569;
  --text-inverse: #F8FAFC;
  --text-link: #1D4ED8;
  --text-link-hover: #1E3A8A;
  --border-light: #D1D9E6;
  --brand-primary: #0B2B4A;
  --brand-accent: #2563EB;
  --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.06);
  --radius: 12px;
  --transition: 0.25s ease;
}

html[data-theme="dark"] {
  --bg-body: #0F172A;
  --bg-card: #1E293B;
  --bg-header: #0B1120;
  --bg-footer: #0B1120;
  --bg-soft: #1E293B;
  --text-primary: #E5E7EB;
  --text-heading: #F8FAFC;
  --text-secondary: #CBD5E1;
  --text-muted: #94A3B8;
  --text-inverse: #F1F5F9;
  --text-link: #60A5FA;
  --text-link-hover: #93C5FD;
  --border-light: #334155;
  --brand-primary: #1E3A5F;
  --brand-accent: #3B82F6;
  --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.4);
}

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", "PingFang SC", "Microsoft YaHei", sans-serif;
  background-color: var(--bg-body);
  color: var(--text-primary);
  line-height: 1.75;
  font-size: 16px;
  transition: background-color var(--transition), color var(--transition);
}

h1,
h2,
h3,
h4 {
  color: var(--text-heading);
  font-weight: 700;
  line-height: 1.35;
  transition: color var(--transition);
}

h1 {
  font-size: 2.2rem;
  letter-spacing: -0.02em;
}

h2 {
  font-size: 1.75rem;
  margin-top: 2.2rem;
  margin-bottom: 1rem;
  border-left: 5px solid var(--brand-accent);
  padding-left: 0.9rem;
}

h3 {
  font-size: 1.35rem;
  margin-top: 1.6rem;
  margin-bottom: 0.7rem;
}

h4 {
  font-size: 1.1rem;
  margin-top: 1.2rem;
  margin-bottom: 0.5rem;
  color: var(--text-secondary);
}

p {
  color: var(--text-primary);
  margin-bottom: 1rem;
  transition: color var(--transition);
}

a {
  color: var(--text-link);
  text-decoration: none;
  transition: color var(--transition);
}

a:hover,
a:focus {
  color: var(--text-link-hover);
  text-decoration: underline;
}

ul,
ol {
  padding-left: 1.6rem;
  margin-bottom: 1rem;
  color: var(--text-primary);
}

li {
  margin-bottom: 0.35rem;
  color: var(--text-primary);
}

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 1.2rem;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 1000;
  background-color: var(--bg-header);
  color: var(--text-inverse);
  box-shadow: 0 2px 10px rgba(0, 0, 0, 0.15);
  transition: background-color var(--transition);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
}

.nav-wrap {
  display: flex;
  align-items: center;
  justify-content: space-between;
  min-height: 66px;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.logo {
  font-size: 1.35rem;
  font-weight: 800;
  color: var(--text-inverse);
  letter-spacing: 0.5px;
  display: flex;
  align-items: center;
  gap: 0.5rem;
  text-decoration: none;
}

.logo:hover {
  color: #FFFFFF;
  text-decoration: none;
}

.logo svg {
  width: 32px;
  height: 32px;
  flex-shrink: 0;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 1.6rem;
  list-style: none;
  padding: 0;
  margin: 0;
  flex-wrap: wrap;
}

.nav-links a {
  color: #E2E8F0;
  font-weight: 500;
  font-size: 0.95rem;
  text-decoration: none;
  padding: 0.3rem 0;
  border-bottom: 2px solid transparent;
  transition: color var(--transition), border-color var(--transition);
}

.nav-links a:hover,
.nav-links a:focus {
  color: #FFFFFF;
  border-bottom-color: var(--brand-accent);
  text-decoration: none;
}

.nav-actions {
  display: flex;
  align-items: center;
  gap: 0.8rem;
}

.theme-toggle,
.menu-toggle {
  background: rgba(255, 255, 255, 0.12);
  border: 1px solid rgba(255, 255, 255, 0.25);
  color: #F1F5F9;
  border-radius: 8px;
  padding: 0.35rem 0.7rem;
  font-size: 0.9rem;
  cursor: pointer;
  transition: background var(--transition), color var(--transition), transform var(--transition);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
}

.theme-toggle:hover,
.menu-toggle:hover {
  background: rgba(255, 255, 255, 0.22);
  color: #FFFFFF;
  transform: translateY(-1px);
}

.menu-toggle {
  display: none;
}

.search-box {
  display: flex;
  align-items: center;
  background: rgba(255, 255, 255, 0.12);
  border-radius: 8px;
  padding: 0.2rem 0.6rem;
  border: 1px solid rgba(255, 255, 255, 0.2);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  transition: border-color var(--transition), background var(--transition);
}

.search-box:focus-within {
  border-color: var(--brand-accent);
  background: rgba(255, 255, 255, 0.18);
}

.search-box input {
  background: transparent;
  border: none;
  color: #F8FAFC;
  padding: 0.4rem 0.3rem;
  font-size: 0.9rem;
  outline: none;
  width: 130px;
}

.search-box input::placeholder {
  color: #CBD5E1;
}

.search-box button {
  background: transparent;
  border: none;
  color: #E2E8F0;
  cursor: pointer;
  padding: 0.2rem 0.3rem;
  transition: color var(--transition), transform var(--transition);
}

.search-box button:hover {
  color: #FFFFFF;
  transform: scale(1.1);
}

@media (max-width: 860px) {
  .nav-links {
    display: none;
    width: 100%;
    flex-direction: column;
    align-items: flex-start;
    gap: 0.5rem;
    padding: 0.8rem 0;
    border-top: 1px solid rgba(255, 255, 255, 0.15);
  }

  .nav-links.open {
    display: flex;
  }

  .menu-toggle {
    display: inline-block;
  }

  .search-box input {
    width: 90px;
  }
}

.hero {
  background: linear-gradient(135deg, #0B2B4A 0%, #123B5E 55%, #1E4A73 100%);
  color: #FFFFFF;
  padding: 3.5rem 0 3rem;
  position: relative;
  overflow: hidden;
}

.hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background: radial-gradient(circle at 15% 80%, rgba(37, 99, 235, 0.2), transparent 50%);
  pointer-events: none;
}

.hero::after {
  content: "";
  position: absolute;
  inset: 0;
  background: radial-gradient(circle at 85% 20%, rgba(37, 99, 235, 0.25), transparent 55%);
  pointer-events: none;
}

.hero-content {
  position: relative;
  z-index: 1;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 2.5rem;
  align-items: center;
}

@media (max-width: 860px) {
  .hero-content {
    grid-template-columns: 1fr;
    gap: 1.8rem;
  }
}

.hero h1 {
  color: #FFFFFF;
  font-size: 2.4rem;
  margin-bottom: 1rem;
  text-shadow: 0 2px 6px rgba(0, 0, 0, 0.25);
}

.hero p {
  color: #E2E8F0;
  font-size: 1.08rem;
  margin-bottom: 1.2rem;
}

.hero-badge {
  display: inline-block;
  background: rgba(255, 255, 255, 0.15);
  border: 1px solid rgba(255, 255, 255, 0.3);
  color: #F8FAFC;
  padding: 0.3rem 0.9rem;
  border-radius: 50px;
  font-size: 0.85rem;
  margin-bottom: 1rem;
  letter-spacing: 0.5px;
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
}

.hero-actions {
  display: flex;
  gap: 1rem;
  flex-wrap: wrap;
}

.btn {
  display: inline-block;
  padding: 0.7rem 1.6rem;
  border-radius: 8px;
  font-weight: 600;
  font-size: 0.95rem;
  text-decoration: none;
  transition: all var(--transition);
  cursor: pointer;
  border: none;
  text-align: center;
}

.btn-primary {
  background: #FFFFFF;
  color: #0B2B4A;
}

.btn-primary:hover {
  background: #E2E8F0;
  color: #0B2B4A;
  text-decoration: none;
  transform: translateY(-2px);
  box-shadow: 0 8px 20px rgba(0, 0, 0, 0.2);
}

.btn-outline {
  background: transparent;
  color: #FFFFFF;
  border: 1.5px solid rgba(255, 255, 255, 0.7);
}

.btn-outline:hover {
  background: rgba(255, 255, 255, 0.12);
  color: #FFFFFF;
  text-decoration: none;
  transform: translateY(-2px);
  box-shadow: 0 8px 20px rgba(0, 0, 0, 0.15);
}

.banner-slider {
  position: relative;
  border-radius: var(--radius);
  overflow: hidden;
  box-shadow: 0 12px 30px rgba(0, 0, 0, 0.3);
  background: rgba(15, 30, 46, 0.75);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border: 1px solid rgba(255, 255, 255, 0.08);
}

.slide {
  display: none;
  padding: 2.2rem 1.8rem;
  min-height: 220px;
  align-items: center;
  justify-content: center;
  text-align: center;
  flex-direction: column;
}

.slide.active {
  display: flex;
  animation: slideFadeIn 0.5s ease;
}

@keyframes slideFadeIn {
  from {
    opacity: 0;
    transform: translateY(10px);
  }

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

.slide svg {
  width: 100%;
  max-width: 320px;
  height: auto;
  margin-bottom: 0.8rem;
  border-radius: 8px;
}

.slide h3 {
  color: #FFFFFF;
  font-size: 1.2rem;
  margin-bottom: 0.4rem;
}

.slide p {
  color: #CBD5E1;
  font-size: 0.92rem;
  margin-bottom: 0;
}

.slider-dots {
  display: flex;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.6rem 0 1rem;
}

.slider-dots span {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.35);
  cursor: pointer;
  transition: background var(--transition), transform var(--transition);
}

.slider-dots span:hover {
  transform: scale(1.2);
}

.slider-dots span.active {
  background: #FFFFFF;
  transform: scale(1.15);
}

.breadcrumb {
  background: var(--bg-soft);
  padding: 0.7rem 0;
  font-size: 0.9rem;
  color: var(--text-secondary);
  border-bottom: 1px solid var(--border-light);
  transition: background-color var(--transition), color var(--transition);
}

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

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

.section {
  padding: 2.5rem 0;
}

.section-alt {
  background: var(--bg-soft);
}

.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 1.5rem;
  margin-top: 1.5rem;
}

.card {
  background: var(--bg-card);
  border: 1px solid var(--border-light);
  border-radius: var(--radius);
  padding: 1.5rem;
  box-shadow: var(--shadow-sm);
  transition: transform var(--transition), box-shadow var(--transition), background-color var(--transition), border-color var(--transition);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
}

.card:hover {
  transform: translateY(-4px);
  box-shadow: 0 10px 24px rgba(0, 0, 0, 0.1);
}

.card h3 {
  margin-top: 0;
  color: var(--text-heading);
}

.card p,
.card li {
  color: var(--text-primary);
}

.card .meta {
  color: var(--text-muted);
  font-size: 0.85rem;
}

.article-item {
  background: var(--bg-card);
  border: 1px solid var(--border-light);
  border-radius: var(--radius);
  padding: 1.3rem 1.5rem;
  margin-bottom: 1.2rem;
  transition: background-color var(--transition), border-color var(--transition), transform var(--transition), box-shadow var(--transition);
}

.article-item:hover {
  transform: translateX(4px);
  box-shadow: 0 6px 18px rgba(0, 0, 0, 0.08);
}

.article-item h3 {
  margin-top: 0;
  margin-bottom: 0.4rem;
}

.article-item .article-meta {
  color: var(--text-muted);
  font-size: 0.85rem;
  margin-bottom: 0.5rem;
}

.article-item p {
  color: var(--text-primary);
  margin-bottom: 0.5rem;
}

.read-more {
  color: var(--text-link);
  font-weight: 600;
  font-size: 0.92rem;
  transition: color var(--transition), letter-spacing var(--transition);
}

.read-more:hover {
  color: var(--text-link-hover);
  letter-spacing: 0.5px;
}

.faq-item {
  background: var(--bg-card);
  border: 1px solid var(--border-light);
  border-radius: var(--radius);
  margin-bottom: 0.8rem;
  overflow: hidden;
  transition: background-color var(--transition), border-color var(--transition), box-shadow var(--transition);
}

.faq-item:hover {
  box-shadow: 0 4px 14px rgba(0, 0, 0, 0.07);
}

.faq-question {
  width: 100%;
  text-align: left;
  background: transparent;
  border: none;
  padding: 1rem 1.3rem;
  font-size: 1.02rem;
  font-weight: 600;
  color: var(--text-heading);
  cursor: pointer;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 1rem;
  transition: background-color var(--transition), color var(--transition);
}

.faq-question:hover {
  background: var(--bg-soft);
}

.faq-question .icon {
  font-size: 1.3rem;
  color: var(--brand-accent);
  transition: transform var(--transition);
  flex-shrink: 0;
}

.faq-item.open .faq-question .icon {
  transform: rotate(45deg);
}

.faq-answer {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.35s ease, padding var(--transition);
  padding: 0 1.3rem;
}

.faq-item.open .faq-answer {
  max-height: 500px;
  padding: 0 1.3rem 1.2rem;
}

.faq-answer p {
  color: var(--text-primary);
  margin-bottom: 0.5rem;
}

.howto-step {
  background: var(--bg-card);
  border-left: 5px solid var(--brand-accent);
  border-radius: 0 var(--radius) var(--radius) 0;
  padding: 1.2rem 1.5rem;
  margin-bottom: 1rem;
  box-shadow: var(--shadow-sm);
  transition: background-color var(--transition), transform var(--transition), box-shadow var(--transition);
}

.howto-step:hover {
  transform: translateX(4px);
  box-shadow: 0 6px 18px rgba(0, 0, 0, 0.08);
}

.howto-step h4 {
  color: var(--text-heading);
  margin-top: 0;
}

.howto-step p,
.howto-step li {
  color: var(--text-primary);
}

.table-wrap {
  overflow-x: auto;
  margin: 1.2rem 0;
}

table {
  width: 100%;
  border-collapse: collapse;
  background: var(--bg-card);
  border-radius: var(--radius);
  overflow: hidden;
  font-size: 0.95rem;
}

th,
td {
  padding: 0.8rem 1rem;
  text-align: left;
  border-bottom: 1px solid var(--border-light);
  color: var(--text-primary);
}

th {
  background: var(--bg-soft);
  color: var(--text-heading);
  font-weight: 700;
}

tr {
  transition: background-color var(--transition);
}

tbody tr:hover {
  background: var(--bg-soft);
}

.testimonial {
  background: var(--bg-card);
  border: 1px solid var(--border-light);
  border-radius: var(--radius);
  padding: 1.5rem;
  box-shadow: var(--shadow-sm);
  transition: background-color var(--transition), border-color var(--transition), transform var(--transition), box-shadow var(--transition);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
}

.testimonial:hover {
  transform: translateY(-4px);
  box-shadow: 0 10px 24px rgba(0, 0, 0, 0.1);
}

.testimonial p {
  color: var(--text-primary);
  font-style: italic;
}

.testimonial .author {
  color: var(--text-secondary);
  font-weight: 600;
  font-size: 0.92rem;
  margin-top: 0.6rem;
}

.tag {
  display: inline-block;
  background: var(--bg-soft);
  color: var(--text-secondary);
  border: 1px solid var(--border-light);
  border-radius: 50px;
  padding: 0.2rem 0.8rem;
  font-size: 0.82rem;
  margin: 0.15rem;
  transition: background-color var(--transition), color var(--transition), transform var(--transition);
}

.tag:hover {
  transform: translateY(-1px);
  background: var(--brand-accent);
  color: #FFFFFF;
}

.contact-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 1.5rem;
}

.contact-item {
  background: var(--bg-card);
  border: 1px solid var(--border-light);
  border-radius: var(--radius);
  padding: 1.3rem;
  transition: background-color var(--transition), border-color var(--transition), transform var(--transition), box-shadow var(--transition);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
}

.contact-item:hover {
  transform: translateY(-4px);
  box-shadow: 0 10px 24px rgba(0, 0, 0, 0.1);
}

.contact-item h4 {
  color: var(--text-heading);
  margin-top: 0;
  margin-bottom: 0.4rem;
}

.contact-item p {
  color: var(--text-primary);
  margin-bottom: 0.2rem;
}

.site-footer {
  background: var(--bg-footer);
  color: var(--text-inverse);
  padding: 2.5rem 0 1.5rem;
  margin-top: 2rem;
  transition: background-color var(--transition);
}

.footer-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 2rem;
  margin-bottom: 1.8rem;
}

.site-footer h4 {
  color: #F8FAFC;
  font-size: 1rem;
  margin-bottom: 0.8rem;
}

.site-footer p,
.site-footer li,
.site-footer a {
  color: #CBD5E1;
  font-size: 0.9rem;
}

.site-footer a:hover {
  color: #FFFFFF;
  text-decoration: underline;
}

.site-footer ul {
  list-style: none;
  padding: 0;
}

.footer-bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.15);
  padding-top: 1.2rem;
  text-align: center;
  font-size: 0.85rem;
  color: #94A3B8;
}

.footer-bottom a {
  color: #CBD5E1;
}

.back-to-top {
  position: fixed;
  right: 1.5rem;
  bottom: 1.5rem;
  z-index: 999;
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background: var(--brand-accent);
  color: #FFFFFF;
  border: none;
  cursor: pointer;
  font-size: 1.3rem;
  display: none;
  align-items: center;
  justify-content: center;
  box-shadow: 0 6px 16px rgba(0, 0, 0, 0.25);
  transition: background var(--transition), transform var(--transition), box-shadow var(--transition);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
}

.back-to-top.show {
  display: flex;
}

.back-to-top:hover {
  background: var(--brand-primary);
  transform: translateY(-3px);
  box-shadow: 0 10px 22px rgba(0, 0, 0, 0.3);
}

.stat-number {
  font-size: 2rem;
  font-weight: 800;
  color: var(--brand-accent);
  line-height: 1.2;
}

.stat-label {
  color: var(--text-secondary);
  font-size: 0.9rem;
}

.reveal {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

.reveal.visible {
  opacity: 1;
  transform: translateY(0);
}

.anchor-nav {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin: 1rem 0 1.5rem;
}

.anchor-nav a {
  background: var(--bg-card);
  border: 1px solid var(--border-light);
  border-radius: 50px;
  padding: 0.3rem 0.9rem;
  font-size: 0.88rem;
  color: var(--text-link);
  transition: background var(--transition), color var(--transition), transform var(--transition), box-shadow var(--transition);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
}

.anchor-nav a:hover {
  background: var(--brand-accent);
  color: #FFFFFF;
  text-decoration: none;
  transform: translateY(-2px);
  box-shadow: 0 6px 14px rgba(37, 99, 235, 0.25);
}

.author-box {
  display: flex;
  gap: 1rem;
  align-items: flex-start;
  background: var(--bg-card);
  border: 1px solid var(--border-light);
  border-radius: var(--radius);
  padding: 1.2rem 1.5rem;
  margin-top: 1.5rem;
  transition: background-color var(--transition), border-color var(--transition), box-shadow var(--transition);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
}

.author-box:hover {
  box-shadow: 0 8px 20px rgba(0, 0, 0, 0.08);
}

.author-box svg {
  width: 56px;
  height: 56px;
  flex-shrink: 0;
  border-radius: 50%;
}

.author-box .author-info h4 {
  margin: 0 0 0.2rem;
  color: var(--text-heading);
}

.author-box .author-info p {
  color: var(--text-secondary);
  font-size: 0.9rem;
  margin-bottom: 0.2rem;
}

.security-note {
  background: var(--bg-soft);
  border: 1px solid var(--border-light);
  border-radius: var(--radius);
  padding: 1rem 1.3rem;
  font-size: 0.9rem;
  color: var(--text-secondary);
  transition: background-color var(--transition), color var(--transition);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
}

@media (max-width: 640px) {
  h1 {
    font-size: 1.7rem;
  }

  h2 {
    font-size: 1.4rem;
  }

  h3 {
    font-size: 1.15rem;
  }

  .hero h1 {
    font-size: 1.75rem;
  }

  .section {
    padding: 1.8rem 0;
  }

  .stat-number {
    font-size: 1.6rem;
  }

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

a:focus-visible,
button:focus-visible,
input:focus-visible {
  outline: 2px solid var(--brand-accent);
  outline-offset: 2px;
}

@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;
  }

  .reveal {
    opacity: 1;
    transform: none;
  }
}