```css
/* ---------- 全局设计变量 ---------- */
:root {
  --bg-body: #f8fafc;
  --bg-surface: #ffffff;
  --bg-card: #ffffff;
  --text-primary: #17202A;
  --text-secondary: #1F2937;
  --text-heading: #0F172A;
  --text-link: #0B4F8A;
  --text-btn: #ffffff;
  --border-light: #e2e8f0;
  --brand-main: #0A2540;
  --brand-accent: #1e4a7a;
  --nav-bg: #ffffff;
  --footer-bg: #0F172A;
  --footer-text: #E2E8F0;
  --footer-heading: #F8FAFC;
  --shadow-sm: 0 4px 12px rgba(0,0,0,0.06);
  --radius-lg: 24px;
  --radius-md: 16px;
  --radius-sm: 8px;
  --glass-bg: rgba(255, 255, 255, 0.7);
  --glass-border: rgba(255, 255, 255, 0.3);
  --glass-shadow: 0 8px 32px rgba(0, 0, 0, 0.08);
}

/* 暗黑模式变量 */
[data-theme="dark"] {
  --bg-body: #0B1220;
  --bg-surface: #111C2E;
  --bg-card: #152238;
  --text-primary: #E2E8F0;
  --text-secondary: #CBD5E1;
  --text-heading: #F8FAFC;
  --text-link: #7BB3E0;
  --border-light: #2D3A4F;
  --brand-main: #1E3A5F;
  --brand-accent: #2E5A8A;
  --nav-bg: #111C2E;
  --footer-bg: #0A1526;
  --footer-text: #CBD5E1;
  --footer-heading: #F1F5F9;
  --shadow-sm: 0 4px 16px rgba(0,0,0,0.6);
  --glass-bg: rgba(17, 28, 46, 0.7);
  --glass-border: rgba(255, 255, 255, 0.1);
  --glass-shadow: 0 8px 32px rgba(0, 0, 0, 0.4);
}

/* ---------- 基础重置 ---------- */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: system-ui, -apple-system, "Segoe UI", Roboto, "PingFang SC", "Microsoft YaHei", sans-serif;
  background-color: var(--bg-body);
  color: var(--text-primary);
  line-height: 1.7;
  font-size: 16px;
  transition: background-color 0.3s, color 0.3s;
  -webkit-font-smoothing: antialiased;
}

h1, h2, h3, h4 {
  color: var(--text-heading);
  font-weight: 700;
  line-height: 1.3;
  transition: color 0.3s;
}

h1 {
  font-size: 2.4rem;
  letter-spacing: -0.02em;
  margin-bottom: 1rem;
}

h2 {
  font-size: 2rem;
  margin: 2rem 0 1.2rem;
  border-left: 6px solid var(--brand-accent);
  padding-left: 1rem;
}

h3 {
  font-size: 1.4rem;
  margin: 1.8rem 0 0.8rem;
}

h4 {
  font-size: 1.2rem;
  margin: 1.2rem 0 0.5rem;
  color: var(--text-secondary);
}

p {
  margin-bottom: 1.2rem;
  color: var(--text-primary);
}

a {
  color: var(--text-link);
  text-decoration: none;
  font-weight: 500;
  border-bottom: 1px solid transparent;
  transition: color 0.2s, border-color 0.2s;
}

a:hover {
  border-bottom-color: var(--text-link);
}

img, svg {
  max-width: 100%;
  height: auto;
  display: block;
}

.container {
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 24px;
}

/* ---------- 导航栏 ---------- */
.navbar {
  background-color: var(--nav-bg);
  box-shadow: var(--shadow-sm);
  position: sticky;
  top: 0;
  z-index: 1000;
  transition: background-color 0.3s, box-shadow 0.3s;
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  background-color: var(--glass-bg);
  border-bottom: 1px solid var(--glass-border);
}

.navbar .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  padding-top: 0.8rem;
  padding-bottom: 0.8rem;
}

.logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 1.7rem;
  font-weight: 800;
  color: var(--text-heading);
  transition: transform 0.2s;
}

.logo:hover {
  transform: scale(1.02);
}

.logo svg {
  width: 38px;
  height: 38px;
  filter: drop-shadow(0 2px 4px rgba(0,0,0,0.1));
}

.nav-links {
  display: flex;
  gap: 2rem;
  list-style: none;
  font-weight: 500;
}

.nav-links a {
  color: var(--text-primary);
  border-bottom: none;
  padding: 0.4rem 0;
  font-size: 1.05rem;
  position: relative;
  transition: color 0.2s;
}

.nav-links a::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--brand-accent);
  transition: width 0.3s ease;
}

.nav-links a:hover {
  color: var(--brand-accent);
}

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

.nav-actions {
  display: flex;
  gap: 1rem;
  align-items: center;
}

.theme-toggle, .search-btn {
  background: var(--bg-surface);
  border: 1px solid var(--border-light);
  border-radius: 40px;
  padding: 0.4rem 0.9rem;
  cursor: pointer;
  color: var(--text-primary);
  font-weight: 500;
  transition: all 0.2s;
  backdrop-filter: blur(8px);
}

.theme-toggle:hover, .search-btn:hover {
  background: var(--brand-accent);
  color: white;
  border-color: var(--brand-accent);
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(30, 74, 122, 0.3);
}

.mobile-menu-btn {
  display: none;
  background: none;
  border: none;
  font-size: 2rem;
  color: var(--text-primary);
  cursor: pointer;
  transition: transform 0.2s;
}

.mobile-menu-btn:hover {
  transform: scale(1.1);
}

@media (max-width: 900px) {
  .nav-links {
    display: none;
    width: 100%;
    flex-direction: column;
    gap: 0.8rem;
    padding: 1rem 0;
    border-top: 1px solid var(--border-light);
  }
  
  .nav-links.active {
    display: flex;
  }
  
  .mobile-menu-btn {
    display: block;
  }
}

/* ---------- 站内搜索区域 ---------- */
.search-wrap {
  background: var(--bg-surface);
  padding: 1.5rem 0;
  border-bottom: 1px solid var(--border-light);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  background-color: var(--glass-bg);
}

.search-box {
  display: flex;
  gap: 0.8rem;
}

.search-box input {
  flex: 1;
  padding: 0.9rem 1.2rem;
  border-radius: 60px;
  border: 1px solid var(--border-light);
  background: var(--bg-body);
  color: var(--text-primary);
  font-size: 1rem;
  transition: border-color 0.2s, box-shadow 0.2s;
}

.search-box input:focus {
  outline: none;
  border-color: var(--brand-accent);
  box-shadow: 0 0 0 3px rgba(30, 74, 122, 0.1);
}

.search-box button {
  background: var(--brand-main);
  border: none;
  color: white;
  padding: 0 1.8rem;
  border-radius: 60px;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.2s;
}

.search-box button:hover {
  background: var(--brand-accent);
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(30, 74, 122, 0.3);
}

/* ---------- Hero Banner ---------- */
.hero {
  background: linear-gradient(135deg, #0A2540 0%, #1e4a7a 50%, #2E5A8A 100%);
  color: white;
  padding: 4rem 0;
  border-radius: 0 0 40px 40px;
  position: relative;
  overflow: hidden;
}

.hero::before {
  content: '';
  position: absolute;
  top: -50%;
  right: -20%;
  width: 60%;
  height: 200%;
  background: radial-gradient(circle, rgba(255,255,255,0.08) 0%, transparent 70%);
  transform: rotate(15deg);
  pointer-events: none;
}

.hero .container {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 2rem;
  position: relative;
  z-index: 1;
}

.hero-text {
  flex: 1 1 400px;
}

.hero-text h1 {
  color: #ffffff;
  font-size: 3rem;
  margin-bottom: 1.2rem;
  text-shadow: 0 2px 8px rgba(0,0,0,0.2);
  animation: fadeInUp 0.8s ease-out;
}

.hero-text p {
  color: #E2E8F0;
  font-size: 1.2rem;
  max-width: 600px;
  animation: fadeInUp 0.8s ease-out 0.1s both;
}

.hero-cta {
  margin-top: 2rem;
  display: flex;
  gap: 1rem;
  animation: fadeInUp 0.8s ease-out 0.2s both;
}

.btn {
  background: #ffffff;
  color: #0A2540;
  font-weight: 700;
  padding: 0.8rem 2rem;
  border-radius: 60px;
  border: none;
  cursor: pointer;
  font-size: 1rem;
  transition: all 0.2s;
  box-shadow: 0 4px 12px rgba(0,0,0,0.1);
}

.btn:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 20px rgba(0,0,0,0.2);
}

.btn-outline {
  background: transparent;
  border: 2px solid #fff;
  color: white;
}

.btn-outline:hover {
  background: rgba(255,255,255,0.1);
  border-color: rgba(255,255,255,0.8);
}

.hero-visual svg {
  width: 280px;
  max-width: 100%;
  animation: float 3s ease-in-out infinite;
  filter: drop-shadow(0 8px 24px rgba(0,0,0,0.2));
}

@keyframes float {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-10px); }
}

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

/* ---------- 卡片通用 ---------- */
.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 2rem;
  margin: 2rem 0;
}

.card {
  background: var(--bg-card);
  border-radius: var(--radius-md);
  padding: 1.8rem;
  box-shadow: var(--shadow-sm);
  border: 1px solid var(--border-light);
  transition: all 0.3s ease;
  position: relative;
  overflow: hidden;
}

.card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: linear-gradient(135deg, rgba(30, 74, 122, 0.02) 0%, transparent 50%);
  opacity: 0;
  transition: opacity 0.3s;
  pointer-events: none;
}

.card:hover {
  transform: translateY(-4px);
  box-shadow: 0 12px 32px rgba(0,0,0,0.1);
  border-color: var(--brand-accent);
}

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

.card h3 {
  margin-top: 0;
  margin-bottom: 0.8rem;
  position: relative;
}

.card p {
  color: var(--text-secondary);
  position: relative;
}

.badge {
  background: var(--brand-accent);
  color: white;
  padding: 0.2rem 1rem;
  border-radius: 40px;
  font-size: 0.85rem;
  display: inline-block;
  margin-bottom: 0.8rem;
  transition: transform 0.2s;
}

.card:hover .badge {
  transform: scale(1.05);
}

/* ---------- 表格 ---------- */
.data-table {
  width: 100%;
  border-collapse: collapse;
  margin: 2rem 0;
  border-radius: var(--radius-sm);
  overflow: hidden;
  box-shadow: var(--shadow-sm);
}

.data-table th {
  background: var(--brand-main);
  color: white;
  padding: 12px 16px;
  text-align: left;
  font-weight: 600;
}

.data-table td {
  padding: 12px 16px;
  border-bottom: 1px solid var(--border-light);
  color: var(--text-primary);
  transition: background-color 0.2s;
}

.data-table tr:hover td {
  background-color: rgba(30, 74, 122, 0.05);
}

/* ---------- FAQ 手风琴 ---------- */
.faq-item {
  background: var(--bg-card);
  border-radius: var(--radius-sm);
  margin-bottom: 1rem;
  border: 1px solid var(--border-light);
  overflow: hidden;
  transition: all 0.3s ease;
}

.faq-item:hover {
  border-color: var(--brand-accent);
  box-shadow: 0 4px 12px rgba(0,0,0,0.08);
}

.faq-question {
  padding: 1.2rem 1.5rem;
  font-weight: 700;
  cursor: pointer;
  display: flex;
  justify-content: space-between;
  align-items: center;
  color: var(--text-heading);
  transition: background-color 0.2s;
  user-select: none;
}

.faq-question:hover {
  background-color: rgba(30, 74, 122, 0.05);
}

.faq-question span {
  font-size: 1.5rem;
  font-weight: 300;
  transition: transform 0.3s;
  color: var(--brand-accent);
}

.faq-item.open .faq-question span {
  transform: rotate(180deg);
}

.faq-answer {
  padding: 0 1.5rem 1.5rem;
  color: var(--text-primary);
  display: none;
  animation: fadeIn 0.3s ease-out;
}

.faq-item.open .faq-answer {
  display: block;
}

@keyframes fadeIn {
  from { opacity: 0; }
  to { opacity: 1; }
}

/* ---------- Footer ---------- */
.footer {
  background: var(--footer-bg);
  color: var(--footer-text);
  padding: 3rem 0 1.5rem;
  margin-top: 4rem;
  position: relative;
}

.footer::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 4px;
  background: linear-gradient(90deg, var(--brand-accent), transparent);
}

.footer h4 {
  color: var(--footer-heading);
  margin-bottom: 1rem;
}

.footer a {
  color: var(--footer-text);
  border-bottom: 1px solid rgba(255,255,255,0.2);
  transition: all 0.2s;
}

.footer a:hover {
  color: var(--footer-heading);
  border-bottom-color: var(--footer-heading);
}

.footer .copyright {
  border-top: 1px solid rgba(255,255,255,0.2);
  margin-top: 2rem;
  padding-top: 1.5rem;
  font-size: 0.9rem;
  color: #CBD5E1;
  text-align: center;
}

/* ---------- 返回顶部 ---------- */
.back-to-top {
  position: fixed;
  bottom: 2rem;
  right: 2rem;
  background: var(--brand-main);
  color: white;
  width: 48px;
  height: 48px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.8rem;
  cursor: pointer;
  border: none;
  z-index: 999;
  box-shadow: 0 8px 20px rgba(0,0,0,0.2);
  transition: all 0.3s;
  opacity: 0;
  visibility: hidden;
  transform: translateY(20px);
}

.back-to-top.show {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.back-to-top:hover {
  background: var(--brand-accent);
  transform: translateY(-4px);
  box-shadow: 0 12px 24px rgba(30, 74, 122, 0.3);
}

/* ---------- 动画 ---------- */
.reveal {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 0.6s, transform 0.6s;
}

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

/* ---------- 数字动画 ---------- */
.stat-number {
  font-size: 2.5rem;
  font-weight: 800;
  color: var(--brand-accent);
  transition: color 0.3s;
}

/* ---------- 面包屑 ---------- */
.breadcrumb {
  padding: 1rem 0;
  color: var(--text-secondary);
  font-size: 0.95rem;
}

.breadcrumb a {
  color: var(--text-link);
  transition: color 0.2s;
}

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

/* ---------- 链接块 ---------- */
.link-group {
  display: flex;
  flex-wrap: wrap;
  gap: 1.2rem;
}

.link-group a {
  color: var(--text-link);
  transition: all 0.2s;
}

.link-group a:hover {
  color: var(--brand-accent);
  transform: translateX(2px);
}

/* ---------- 特殊区块样式 ---------- */
section[id] {
  padding: 2rem 0;
  scroll-margin-top: 80px;
}

/* 产品介绍区块 */
#brand .card-grid,
#solutions .card-grid {
  gap: 1.5rem;
}

/* 内嵌内容区块 */
#brand > div,
#solutions > div,
#contact > div {
  background: var(--bg-surface);
  padding: 2rem;
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-sm);
  border: 1px solid var(--border-light);
  transition: all 0.3s;
}

#brand > div:hover,
#solutions > div:hover,
#contact > div:hover {
  box-shadow: 0 8px 24px rgba(0,0,0,0.08);
}

/* 文章卡片 */
#articles .card {
  display: flex;
  flex-direction: column;
}

#articles .card a {
  margin-top: auto;
  align-self: flex-start;
  font-weight: 600;
}

/* HowTo 区块 */
#howto {
  background: var(--bg-surface);
  border-radius: var(--radius-md);
  padding: 2rem;
  border: 1px solid var(--border-light);
}

/* 联系区块 */
#contact .card {
  text-align: center;
}

#contact .card p {
  margin-bottom: 0.5rem;
}

/* 友情链接和网站地图 */
#contact > div:last-child {
  background: transparent;
  border: none;
  box-shadow: none;
  padding: 0;
}

/* ---------- 响应式适配 ---------- */
@media (max-width: 768px) {
  h1 {
    font-size: 2rem;
  }
  
  h2 {
    font-size: 1.6rem;
  }
  
  h3 {
    font-size: 1.2rem;
  }
  
  .hero-text h1 {
    font-size: 2.2rem;
  }
  
  .hero-text p {
    font-size: 1rem;
  }
  
  .hero-cta {
    flex-direction: column;
  }
  
  .btn {
    width: 100%;
    text-align: center;
  }
  
  .card-grid {
    grid-template-columns: 1fr;
    gap: 1.5rem;
  }
  
  .back-to-top {
    bottom: 1rem;
    right: 1rem;
    width: 40px;
    height: 40px;
    font-size: 1.4rem;
  }
  
  .search-box {
    flex-direction: column;
  }
  
  .search-box button {
    padding: 0.8rem;
  }
  
  #brand > div,
  #solutions > div,
  #contact > div {
    padding: 1.5rem;
  }
}

@media (max-width: 480px) {
  .container {
    padding: 0 16px;
  }
  
  .logo {
    font-size: 1.4rem;
  }
  
  .logo svg {
    width: 32px;
    height: 32px;
  }
  
  .nav-actions {
    gap: 0.5rem;
  }
  
  .theme-toggle, .search-btn {
    padding: 0.3rem 0.7rem;
    font-size: 0.9rem;
  }
  
  .hero {
    padding: 3rem 0;
    border-radius: 0 0 24px 24px;
  }
  
  .hero-text h1 {
    font-size: 1.8rem;
  }
  
  .faq-question {
    font-size: 0.95rem;
  }
}

/* ---------- 滚动条美化 ---------- */
::-webkit-scrollbar {
  width: 8px;
  height: 8px;
}

::-webkit-scrollbar-track {
  background: var(--bg-body);
}

::-webkit-scrollbar-thumb {
  background: var(--brand-accent);
  border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
  background: var(--brand-main);
}

/* ---------- 选中文本样式 ---------- */
::selection {
  background: var(--brand-accent);
  color: white;
}

/* ---------- 焦点可见性 ---------- */
:focus-visible {
  outline: 3px solid var(--brand-accent);
  outline-offset: 2px;
  border-radius: 4px;
}

/* ---------- 减少动画偏好 ---------- */
@media (prefers-reduced-motion: reduce) {
  * {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
}
```