```css
/* ---------- 设计变量与重置 ---------- */
:root {
  --bg-primary: #f8fafc;
  --bg-card: #ffffff;
  --bg-footer: #0f1c2e;
  --text-heading: #1e293b;
  --text-body: #243447;
  --text-secondary: #3e4c63;
  --text-footer: #e2e8f0;
  --text-footer-muted: #b0c4de;
  --brand-primary: #1a4b8c;
  --brand-dark: #0d2f57;
  --link-color: #1a4b8c;
  --link-hover: #0d2f57;
  --border-soft: #dce3ec;
  --nav-bg: #ffffff;
  --nav-shadow: 0 4px 12px rgba(0, 0, 0, 0.04);
  --btn-bg: #1a4b8c;
  --btn-text: #ffffff;
  --btn-hover: #0d2f57;
  --card-shadow: 0 8px 20px rgba(0, 0, 0, 0.03);
  --badge-bg: #eaf1fb;
  --badge-text: #0d2f57;
  --glass-bg: rgba(255, 255, 255, 0.7);
  --glass-border: rgba(255, 255, 255, 0.3);
  --gradient-hero: linear-gradient(135deg, #0d2f57 0%, #1a4b8c 50%, #2d6cb5 100%);
  --gradient-card: linear-gradient(145deg, #ffffff 0%, #f0f4fa 100%);
  --hover-lift: translateY(-6px);
  --transition-smooth: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

/* 暗黑模式变量 */
[data-theme="dark"] {
  --bg-primary: #0f172a;
  --bg-card: #1e293b;
  --bg-footer: #0b1322;
  --text-heading: #f8fafc;
  --text-body: #e2e8f0;
  --text-secondary: #cbd5e1;
  --text-footer: #e2e8f0;
  --text-footer-muted: #a0b3cc;
  --brand-primary: #3b82f6;
  --brand-dark: #1d4ed8;
  --link-color: #93c5fd;
  --link-hover: #bfdbfe;
  --border-soft: #334155;
  --nav-bg: #1e293b;
  --nav-shadow: 0 4px 12px rgba(0, 0, 0, 0.5);
  --btn-bg: #3b82f6;
  --btn-text: #ffffff;
  --btn-hover: #1d4ed8;
  --card-shadow: 0 8px 20px rgba(0, 0, 0, 0.4);
  --badge-bg: #334155;
  --badge-text: #e2e8f0;
  --glass-bg: rgba(30, 41, 59, 0.7);
  --glass-border: rgba(255, 255, 255, 0.1);
  --gradient-hero: linear-gradient(135deg, #0b1322 0%, #1a1a2e 50%, #16213e 100%);
  --gradient-card: linear-gradient(145deg, #1e293b 0%, #243244 100%);
}

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

html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  background-color: var(--bg-primary);
  color: var(--text-body);
  line-height: 1.7;
  transition: background-color 0.3s ease, color 0.3s ease;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: hidden;
}

/* 标题颜色 */
h1, h2, h3, h4 {
  color: var(--text-heading);
  font-weight: 700;
  line-height: 1.3;
}

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

h2 {
  font-size: 2rem;
  margin-bottom: 1.2rem;
  border-left: 6px solid var(--brand-primary);
  padding-left: 1rem;
  position: relative;
  overflow: hidden;
}

h2::after {
  content: '';
  position: absolute;
  left: 1rem;
  bottom: -4px;
  width: 60px;
  height: 3px;
  background: var(--brand-primary);
  border-radius: 2px;
  opacity: 0.6;
}

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-heading);
}

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

a {
  color: var(--link-color);
  text-decoration: none;
  transition: color 0.2s;
  font-weight: 500;
}

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

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

/* 导航 */
.site-header {
  background-color: var(--nav-bg);
  box-shadow: var(--nav-shadow);
  position: sticky;
  top: 0;
  z-index: 1000;
  transition: background-color 0.3s;
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  background-color: var(--glass-bg);
  border-bottom: 1px solid var(--glass-border);
}

.nav-wrapper {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 14px 24px;
  max-width: 1280px;
  margin: 0 auto;
}

.logo {
  font-size: 1.8rem;
  font-weight: 800;
  color: var(--brand-primary);
  letter-spacing: -0.5px;
  background: var(--gradient-hero);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  transition: var(--transition-smooth);
}

.logo span {
  color: var(--text-heading);
  -webkit-text-fill-color: var(--text-heading);
}

.logo:hover {
  transform: scale(1.05);
}

.nav-links {
  display: flex;
  gap: 24px;
  align-items: center;
}

.nav-links a {
  color: var(--text-body);
  font-weight: 500;
  position: relative;
  padding: 4px 0;
}

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

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

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

.theme-toggle, .menu-toggle {
  background: none;
  border: none;
  cursor: pointer;
  padding: 8px;
  border-radius: 30px;
  color: var(--text-heading);
  font-size: 1.2rem;
  transition: var(--transition-smooth);
}

.theme-toggle:hover, .menu-toggle:hover {
  transform: rotate(15deg) scale(1.1);
  background: var(--badge-bg);
}

.menu-toggle {
  display: none;
}

.search-box {
  display: flex;
  align-items: center;
  background: var(--bg-primary);
  border: 1px solid var(--border-soft);
  border-radius: 40px;
  padding: 4px 8px 4px 16px;
  transition: var(--transition-smooth);
}

.search-box:focus-within {
  border-color: var(--brand-primary);
  box-shadow: 0 0 0 3px rgba(26, 75, 140, 0.1);
}

.search-box input {
  border: none;
  background: transparent;
  color: var(--text-body);
  padding: 8px 6px;
  font-size: 0.95rem;
  outline: none;
  width: 180px;
}

.search-box button {
  background: var(--btn-bg);
  color: var(--btn-text);
  border: none;
  padding: 6px 14px;
  border-radius: 30px;
  font-weight: 600;
  cursor: pointer;
  transition: var(--transition-smooth);
}

.search-box button:hover {
  background: var(--btn-hover);
  transform: scale(1.05);
}

/* 移动菜单 */
.mobile-nav {
  display: none;
  flex-direction: column;
  background: var(--nav-bg);
  padding: 12px 24px;
  gap: 12px;
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  background-color: var(--glass-bg);
}

.mobile-nav.open {
  display: flex;
  animation: slideDown 0.3s ease;
}

.mobile-nav a {
  padding: 10px 0;
  border-bottom: 1px solid var(--border-soft);
}

.mobile-nav a:last-child {
  border-bottom: none;
}

@keyframes slideDown {
  from {
    opacity: 0;
    transform: translateY(-10px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* 主视觉 */
.hero {
  background: var(--gradient-hero);
  color: white;
  padding: 70px 0 60px;
  margin-bottom: 30px;
  position: relative;
  overflow: hidden;
}

.hero::before {
  content: '';
  position: absolute;
  top: -50%;
  right: -20%;
  width: 600px;
  height: 600px;
  background: radial-gradient(circle, rgba(255, 255, 255, 0.1) 0%, transparent 70%);
  border-radius: 50%;
  animation: float 8s ease-in-out infinite;
}

.hero::after {
  content: '';
  position: absolute;
  bottom: -30%;
  left: -10%;
  width: 400px;
  height: 400px;
  background: radial-gradient(circle, rgba(255, 255, 255, 0.08) 0%, transparent 70%);
  border-radius: 50%;
  animation: float 6s ease-in-out infinite reverse;
}

@keyframes float {
  0%, 100% {
    transform: translateY(0) scale(1);
  }
  50% {
    transform: translateY(-20px) scale(1.05);
  }
}

.hero-content {
  display: grid;
  grid-template-columns: 1.2fr 0.8fr;
  gap: 40px;
  align-items: center;
  position: relative;
  z-index: 1;
}

.hero-text h1 {
  color: #ffffff;
  margin-bottom: 20px;
  font-size: 3rem;
  text-shadow: 0 2px 20px rgba(0, 0, 0, 0.3);
}

.hero-text p {
  color: #e2e8f0;
  font-size: 1.2rem;
  margin-bottom: 25px;
  text-shadow: 0 1px 10px rgba(0, 0, 0, 0.2);
}

.hero-cta {
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
}

.btn-primary {
  background: var(--btn-bg);
  color: var(--btn-text);
  padding: 14px 28px;
  border-radius: 40px;
  font-weight: 600;
  border: none;
  cursor: pointer;
  transition: var(--transition-smooth);
  display: inline-block;
  text-decoration: none;
  box-shadow: 0 4px 15px rgba(26, 75, 140, 0.3);
}

.btn-primary:hover {
  background: var(--btn-hover);
  color: white;
  transform: translateY(-2px) scale(1.02);
  box-shadow: 0 6px 20px rgba(26, 75, 140, 0.4);
}

.btn-outline {
  background: transparent;
  border: 2px solid #d1d9e8;
  color: #e2e8f0;
  padding: 12px 26px;
  border-radius: 40px;
  font-weight: 600;
  cursor: pointer;
  transition: var(--transition-smooth);
}

.btn-outline:hover {
  border-color: white;
  background: rgba(255, 255, 255, 0.08);
  color: white;
  transform: translateY(-2px);
}

.svg-placeholder {
  background: rgba(255, 255, 255, 0.1);
  border-radius: 16px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: #0d2f57;
  font-weight: 600;
  padding: 20px;
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border: 1px solid rgba(255, 255, 255, 0.2);
}

.svg-placeholder svg {
  filter: drop-shadow(0 4px 20px rgba(0, 0, 0, 0.3));
}

/* 卡片通用 */
.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 24px;
  margin: 30px 0;
}

.card {
  background: var(--gradient-card);
  border-radius: 18px;
  padding: 24px;
  box-shadow: var(--card-shadow);
  border: 1px solid var(--border-soft);
  transition: var(--transition-smooth);
  position: relative;
  overflow: hidden;
}

.card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 3px;
  background: var(--gradient-hero);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform 0.4s ease;
}

.card:hover {
  transform: var(--hover-lift);
  box-shadow: 0 12px 30px rgba(0, 0, 0, 0.1);
  border-color: var(--brand-primary);
}

.card:hover::before {
  transform: scaleX(1);
}

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

.card p {
  color: var(--text-body);
}

/* 文章卡片 */
.article-card {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.article-card .meta {
  font-size: 0.85rem;
  color: var(--text-secondary);
  display: inline-block;
  background: var(--badge-bg);
  padding: 2px 10px;
  border-radius: 20px;
  width: fit-content;
}

.article-card .read-more {
  margin-top: auto;
  font-weight: 600;
  transition: var(--transition-smooth);
}

.article-card .read-more:hover {
  transform: translateX(5px);
}

/* FAQ */
.faq-item {
  background: var(--bg-card);
  border-radius: 14px;
  margin-bottom: 12px;
  border: 1px solid var(--border-soft);
  padding: 8px 20px;
  transition: var(--transition-smooth);
  overflow: hidden;
}

.faq-item:hover {
  border-color: var(--brand-primary);
  box-shadow: 0 4px 15px rgba(0, 0, 0, 0.05);
}

.faq-question {
  font-weight: 700;
  font-size: 1.1rem;
  cursor: pointer;
  padding: 14px 0;
  display: flex;
  justify-content: space-between;
  color: var(--text-heading);
  background: none;
  border: none;
  width: 100%;
  text-align: left;
  transition: var(--transition-smooth);
}

.faq-question span {
  transition: transform 0.3s ease;
  font-size: 1.4rem;
  color: var(--brand-primary);
}

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

.faq-answer {
  display: none;
  padding: 0 0 18px 0;
  color: var(--text-body);
  animation: fadeIn 0.3s ease;
}

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

@keyframes fadeIn {
  from {
    opacity: 0;
    transform: translateY(-10px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* 表格 */
.info-table {
  width: 100%;
  border-collapse: collapse;
  background: var(--bg-card);
  border-radius: 16px;
  overflow: hidden;
  margin: 24px 0;
  box-shadow: var(--card-shadow);
}

.info-table th {
  background: var(--brand-primary);
  color: white;
  padding: 14px 18px;
  text-align: left;
  font-weight: 600;
}

.info-table td {
  padding: 14px 18px;
  border-bottom: 1px solid var(--border-soft);
  color: var(--text-body);
  background: var(--bg-card);
  transition: var(--transition-smooth);
}

.info-table tr:hover td {
  background: var(--badge-bg);
}

/* Footer */
.site-footer {
  background-color: var(--bg-footer);
  color: var(--text-footer);
  padding: 40px 0 20px;
  margin-top: 50px;
  position: relative;
}

.site-footer::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 3px;
  background: var(--gradient-hero);
}

.footer-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 30px;
  margin-bottom: 30px;
}

.site-footer h4 {
  color: #ffffff;
  margin-bottom: 16px;
  position: relative;
  padding-bottom: 8px;
}

.site-footer h4::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 30px;
  height: 2px;
  background: var(--brand-primary);
}

.site-footer a {
  color: var(--text-footer-muted);
  transition: var(--transition-smooth);
}

.site-footer a:hover {
  color: white;
  transform: translateX(5px);
  display: inline-block;
}

.copyright {
  border-top: 1px solid #2c3e50;
  padding-top: 20px;
  text-align: center;
  font-size: 0.9rem;
  color: var(--text-footer-muted);
}

/* 面包屑 */
.breadcrumb {
  padding: 20px 0 0;
  font-size: 0.9rem;
  color: var(--text-secondary);
}

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

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

/* 工具类 */
.text-center { text-align: center; }
.mt-2 { margin-top: 2rem; }
.mb-2 { margin-bottom: 2rem; }
.section-title { margin-bottom: 2rem; }

/* 滚动动画 */
.reveal {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.6s, transform 0.6s;
}

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

/* 响应式 */
@media (max-width: 900px) {
  .nav-links { display: none; }
  .menu-toggle { display: block; }
  .mobile-nav.open { display: flex; }
  .hero-content { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr 1fr; }
  .hero-text h1 { font-size: 2.4rem; }
}

@media (max-width: 560px) {
  h1 { font-size: 1.9rem; }
  h2 { font-size: 1.6rem; }
  .footer-grid { grid-template-columns: 1fr; }
  .hero { padding: 50px 0; }
  .hero-text h1 { font-size: 1.8rem; }
  .hero-text p { font-size: 1rem; }
  .hero-cta { flex-direction: column; }
  .btn-primary, .btn-outline { width: 100%; text-align: center; }
  .search-box { display: none; }
  .nav-wrapper { padding: 10px 16px; }
  .logo { font-size: 1.4rem; }
}

/* 图片占位SVG背景文字清晰 */
.svg-placeholder {
  background: rgba(255, 255, 255, 0.1);
  border-radius: 16px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: #0d2f57;
  font-weight: 600;
  padding: 20px;
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
}

/* 返回顶部按钮 */
#backToTop {
  position: fixed;
  bottom: 30px;
  right: 30px;
  background: var(--brand-primary);
  color: white;
  border: none;
  padding: 12px 16px;
  border-radius: 40px;
  font-weight: bold;
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.2);
  display: none;
  cursor: pointer;
  z-index: 999;
  transition: var(--transition-smooth);
  font-size: 1.2rem;
}

#backToTop:hover {
  background: var(--btn-hover);
  transform: translateY(-3px);
  box-shadow: 0 6px 20px rgba(0, 0, 0, 0.3);
}

/* 友情链接区域 */
.friend-links {
  display: flex;
  flex-wrap: wrap;
  gap: 16px;
  background: var(--bg-card);
  padding: 20px;
  border-radius: 16px;
  border: 1px solid var(--border-soft);
}

.friend-links a {
  padding: 8px 16px;
  background: var(--badge-bg);
  border-radius: 20px;
  transition: var(--transition-smooth);
}

.friend-links a:hover {
  background: var(--brand-primary);
  color: white;
  transform: translateY(-2px);
  text-decoration: none;
}

/* HowTo 区域 */
.howto-box {
  background: var(--bg-card);
  padding: 24px;
  border-radius: 20px;
  border: 1px solid var(--border-soft);
  transition: var(--transition-smooth);
}

.howto-box:hover {
  box-shadow: var(--card-shadow);
}

.howto-box ol {
  margin-left: 20px;
  color: var(--text-body);
  counter-reset: custom-counter;
  list-style: none;
}

.howto-box ol li {
  counter-increment: custom-counter;
  position: relative;
  padding: 8px 0 8px 40px;
}

.howto-box ol li::before {
  content: counter(custom-counter);
  position: absolute;
  left: 0;
  top: 8px;
  width: 28px;
  height: 28px;
  background: var(--brand-primary);
  color: white;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.9rem;
  font-weight: 600;
}

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

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

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

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

/* 选择文本 */
::selection {
  background: var(--brand-primary);
  color: white;
}

/* 焦点可见性 */
:focus-visible {
  outline: 2px solid var(--brand-primary);
  outline-offset: 2px;
}

/* 打印样式 */
@media print {
  .site-header, .site-footer, #backToTop, .hero-cta, .search-box {
    display: none !important;
  }
  
  body {
    background: white;
    color: black;
  }
  
  .container {
    max-width: 100%;
    padding: 0;
  }
}
```