```css
/* ===== 全局变量与主题系统 ===== */
:root {
  --bg-primary: #f8f9fc;
  --bg-secondary: #ffffff;
  --bg-card: rgba(255, 255, 255, 0.72);
  --bg-navbar: rgba(255, 255, 255, 0.68);
  --bg-footer: #1a1d29;
  --bg-soft: #eef1f6;
  --bg-hero: linear-gradient(135deg, #fce4ec 0%, #f3e5f5 50%, #e8eaf6 100%);
  --text-primary: #1f2333;
  --text-secondary: #4a4f63;
  --text-heading: #111827;
  --text-link: #3b82f6;
  --text-footer: #cbd5e1;
  --text-btn: #ffffff;
  --border-light: rgba(100, 116, 139, 0.18);
  --brand-color: #e11d48;
  --brand-light: #fb7185;
  --brand-dark: #be123c;
  --shadow-sm: 0 4px 24px rgba(0, 0, 0, 0.06);
  --shadow-md: 0 8px 30px rgba(225, 29, 72, 0.12);
  --shadow-lg: 0 20px 60px rgba(0, 0, 0, 0.08);
  --radius-sm: 12px;
  --radius-md: 20px;
  --radius-lg: 28px;
  --blur: blur(16px) saturate(180%);
  --transition: all 0.35s cubic-bezier(0.4, 0, 0.2, 1);
  --font-sans: system-ui, -apple-system, "Segoe UI", Roboto, "PingFang SC", "Microsoft YaHei", sans-serif;
}

[data-theme="dark"] {
  --bg-primary: #0f1222;
  --bg-secondary: #141829;
  --bg-card: rgba(30, 35, 58, 0.78);
  --bg-navbar: rgba(15, 18, 34, 0.75);
  --bg-footer: #090b14;
  --bg-soft: #1e2338;
  --bg-hero: linear-gradient(135deg, #1e1b4b 0%, #312e81 50%, #1e1b4b 100%);
  --text-primary: #e2e8f0;
  --text-secondary: #a5b0c5;
  --text-heading: #f1f5f9;
  --text-link: #93c5fd;
  --text-footer: #94a3b8;
  --border-light: rgba(148, 163, 184, 0.15);
  --brand-color: #fb7185;
  --brand-light: #fda4af;
  --brand-dark: #e11d48;
  --shadow-sm: 0 4px 24px rgba(0, 0, 0, 0.4);
  --shadow-md: 0 8px 30px rgba(251, 113, 133, 0.15);
  --shadow-lg: 0 20px 60px rgba(0, 0, 0, 0.5);
}

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

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

body {
  font-family: var(--font-sans);
  background: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.7;
  font-size: 16px;
  transition: background 0.4s ease, color 0.4s ease;
  overflow-x: hidden;
}

h1, h2, h3, h4, h5, h6 {
  color: var(--text-heading);
  font-weight: 700;
  line-height: 1.25;
  margin-bottom: 0.6rem;
  letter-spacing: -0.01em;
}

h1 { font-size: clamp(2rem, 5vw, 3rem); }
h2 { font-size: clamp(1.6rem, 3.5vw, 2.4rem); }
h3 { font-size: clamp(1.2rem, 2vw, 1.5rem); }
h4 { font-size: 1.1rem; }

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

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

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

ul, ol {
  list-style-position: inside;
  padding-left: 0;
}

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

button {
  font-family: inherit;
  cursor: pointer;
  border: none;
  background: none;
}

.container {
  width: 100%;
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 clamp(16px, 4vw, 40px);
}

.section-title {
  margin: 3.5rem 0 2rem;
  font-size: clamp(1.5rem, 3vw, 2.2rem);
  border-left: 6px solid var(--brand-color);
  padding-left: clamp(0.8rem, 2vw, 1.5rem);
  position: relative;
}

.section-title::after {
  content: "";
  position: absolute;
  bottom: -8px;
  left: 0;
  width: 60px;
  height: 3px;
  background: var(--brand-color);
  border-radius: 4px;
}

hr {
  border: none;
  border-top: 1px solid var(--border-light);
  margin: 2.5rem 0;
}

/* ===== 导航栏 ===== */
.navbar {
  position: sticky;
  top: 0;
  z-index: 1000;
  background: var(--bg-navbar);
  backdrop-filter: var(--blur);
  -webkit-backdrop-filter: var(--blur);
  border-bottom: 1px solid var(--border-light);
  transition: background 0.4s ease, box-shadow 0.4s ease;
}

.navbar .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  padding-top: 12px;
  padding-bottom: 12px;
  gap: 12px;
}

.logo {
  font-size: 1.4rem;
  font-weight: 800;
  color: var(--text-heading);
  display: flex;
  align-items: center;
  gap: 10px;
  flex-shrink: 0;
}

.logo svg {
  width: 38px;
  height: 38px;
  border-radius: 10px;
  box-shadow: var(--shadow-sm);
}

.logo span {
  background: linear-gradient(135deg, var(--brand-color), var(--brand-light));
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  white-space: nowrap;
}

.nav-links {
  display: flex;
  gap: clamp(0.8rem, 2vw, 1.8rem);
  align-items: center;
  flex-wrap: wrap;
}

.nav-links a {
  color: var(--text-primary);
  font-weight: 500;
  padding: 0.4rem 0.2rem;
  border-bottom: 2px solid transparent;
  transition: border-color 0.3s ease, color 0.3s ease;
  font-size: 0.95rem;
}

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

.nav-actions {
  display: flex;
  gap: 10px;
  align-items: center;
}

.theme-toggle, .menu-btn {
  background: var(--bg-soft);
  border: 1px solid var(--border-light);
  border-radius: 40px;
  padding: 8px 18px;
  font-weight: 600;
  font-size: 0.9rem;
  color: var(--text-primary);
  transition: var(--transition);
  display: flex;
  align-items: center;
  gap: 6px;
}

.theme-toggle:hover {
  background: var(--brand-color);
  color: white;
  border-color: var(--brand-color);
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}

.menu-btn {
  display: none;
  font-size: 1.2rem;
  padding: 6px 14px;
}

/* ===== 移动端菜单 ===== */
@media (max-width: 860px) {
  .nav-links {
    display: none;
    width: 100%;
    order: 3;
    flex-direction: column;
    align-items: flex-start;
    padding: 1rem 0;
    gap: 0.5rem;
    border-top: 1px solid var(--border-light);
    margin-top: 8px;
  }

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

  .nav-links a {
    width: 100%;
    padding: 0.6rem 0.8rem;
    border-radius: 10px;
    font-size: 1rem;
  }

  .nav-links a:hover {
    background: var(--bg-soft);
    border-bottom: none;
  }

  .menu-btn {
    display: inline-flex;
  }
}

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

/* ===== Hero 区域 ===== */
.hero {
  background: var(--bg-hero);
  border-radius: 0 0 48px 48px;
  padding: clamp(2rem, 6vw, 4.5rem) 0;
  position: relative;
  overflow: hidden;
}

.hero::before {
  content: "";
  position: absolute;
  top: -40%;
  right: -20%;
  width: 500px;
  height: 500px;
  background: radial-gradient(circle, rgba(225, 29, 72, 0.12) 0%, transparent 70%);
  border-radius: 50%;
  pointer-events: none;
}

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

.hero-text {
  flex: 1 1 380px;
}

.hero-text h1 {
  font-size: clamp(2rem, 5vw, 3.2rem);
  line-height: 1.15;
  margin-bottom: 1.2rem;
  background: linear-gradient(135deg, var(--text-heading), var(--brand-color));
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
}

.hero-text p {
  font-size: clamp(1rem, 2vw, 1.2rem);
  color: var(--text-secondary);
  max-width: 540px;
  line-height: 1.7;
}

.hero-cta {
  display: flex;
  gap: 1rem;
  margin-top: 2rem;
  flex-wrap: wrap;
}

.btn {
  background: var(--brand-color);
  color: var(--text-btn);
  padding: 0.75rem 2rem;
  border-radius: 60px;
  font-weight: 600;
  font-size: 0.95rem;
  border: none;
  cursor: pointer;
  transition: var(--transition);
  display: inline-flex;
  align-items: center;
  gap: 8px;
  box-shadow: 0 4px 15px rgba(225, 29, 72, 0.25);
}

.btn:hover {
  transform: translateY(-3px);
  box-shadow: 0 8px 25px rgba(225, 29, 72, 0.35);
  text-decoration: none;
  color: white;
}

.btn-outline {
  background: transparent;
  border: 2px solid var(--brand-color);
  color: var(--brand-color);
  box-shadow: none;
}

.btn-outline:hover {
  background: var(--brand-color);
  color: white;
  box-shadow: 0 8px 25px rgba(225, 29, 72, 0.3);
}

.hero-visual {
  flex: 0 0 auto;
  animation: float 6s ease-in-out infinite;
}

.hero-visual svg {
  width: clamp(120px, 18vw, 200px);
  height: auto;
  filter: drop-shadow(0 10px 30px rgba(0, 0, 0, 0.1));
}

@keyframes float {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-15px); }
}

/* ===== 面包屑 ===== */
.breadcrumb {
  padding: 1rem 0;
  font-size: 0.85rem;
  color: var(--text-secondary);
  display: flex;
  align-items: center;
  gap: 6px;
  flex-wrap: wrap;
}

.breadcrumb span {
  opacity: 0.75;
}

.breadcrumb span:last-child {
  color: var(--brand-color);
  opacity: 1;
  font-weight: 500;
}

/* ===== 卡片网格 ===== */
.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 1.5rem;
  margin: 2rem 0;
}

.card {
  background: var(--bg-card);
  backdrop-filter: var(--blur);
  -webkit-backdrop-filter: var(--blur);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-md);
  padding: 1.8rem 1.5rem;
  box-shadow: var(--shadow-sm);
  transition: var(--transition);
  position: relative;
  overflow: hidden;
}

.card::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 4px;
  background: linear-gradient(90deg, var(--brand-color), var(--brand-light));
  transform: scaleX(0);
  transform-origin: left;
  transition: transform 0.4s ease;
}

.card:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-lg);
  border-color: rgba(225, 29, 72, 0.3);
}

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

.card h3 {
  font-size: 1.25rem;
  margin-bottom: 0.8rem;
  display: flex;
  align-items: center;
  gap: 8px;
}

.card p {
  color: var(--text-secondary);
  font-size: 0.9rem;
  margin-bottom: 0;
}

/* ===== 文章列表 ===== */
.article-list {
  margin: 2rem 0;
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.article-item {
  padding: 1.2rem 1rem;
  border-bottom: 1px solid var(--border-light);
  transition: var(--transition);
  border-radius: var(--radius-sm);
  background: transparent;
}

.article-item:hover {
  background: var(--bg-soft);
  padding-left: 1.5rem;
}

.article-item h4 {
  font-size: 1.1rem;
  margin-bottom: 0.3rem;
  transition: color 0.2s;
}

.article-item:hover h4 {
  color: var(--brand-color);
}

.article-meta {
  font-size: 0.8rem;
  color: var(--text-secondary);
  margin-bottom: 0.5rem;
  display: flex;
  gap: 12px;
  align-items: center;
}

.article-item p {
  font-size: 0.9rem;
  color: var(--text-secondary);
  margin-bottom: 0.4rem;
}

.article-item > a {
  font-size: 0.85rem;
  font-weight: 600;
  display: inline-flex;
  align-items: center;
  gap: 4px;
}

/* ===== FAQ 样式 ===== */
.faq-list {
  margin: 2rem 0;
}

.faq-item {
  background: var(--bg-card);
  backdrop-filter: var(--blur);
  -webkit-backdrop-filter: var(--blur);
  border-radius: var(--radius-md);
  padding: 1rem 1.5rem;
  margin-bottom: 0.8rem;
  border: 1px solid var(--border-light);
  cursor: pointer;
  transition: var(--transition);
}

.faq-item:hover {
  border-color: var(--brand-color);
  box-shadow: var(--shadow-sm);
}

.faq-question {
  font-weight: 600;
  font-size: 1rem;
  color: var(--text-heading);
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 12px;
}

.faq-question::after {
  content: "+";
  font-size: 1.5rem;
  color: var(--brand-color);
  transition: transform 0.3s ease;
  flex-shrink: 0;
  line-height: 1;
}

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

.faq-answer {
  display: none;
  padding-top: 0.8rem;
  color: var(--text-primary);
  font-size: 0.9rem;
  border-top: 1px solid var(--border-light);
  margin-top: 0.8rem;
  animation: fadeIn 0.3s ease;
}

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

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(-5px); }
  to { opacity: 1; transform: translateY(0); }
}

/* ===== HowTo 教程 ===== */
.howto-content {
  background: var(--bg-card);
  backdrop-filter: var(--blur);
  -webkit-backdrop-filter: var(--blur);
  padding: clamp(1.5rem, 4vw, 2.5rem);
  border-radius: var(--radius-lg);
  border: 1px solid var(--border-light);
  box-shadow: var(--shadow-sm);
}

.howto-content p {
  margin-bottom: 0.8rem;
  font-size: 0.95rem;
}

.howto-content strong {
  color: var(--brand-color);
  margin-right: 6px;
}

/* ===== 联系区域 ===== */
.contact-grid {
  display: flex;
  gap: clamp(1.5rem, 4vw, 3rem);
  flex-wrap: wrap;
  margin-bottom: 2rem;
}

.contact-grid > div {
  flex: 1 1 200px;
  background: var(--bg-card);
  backdrop-filter: var(--blur);
  -webkit-backdrop-filter: var(--blur);
  padding: 1.5rem;
  border-radius: var(--radius-md);
  border: 1px solid var(--border-light);
}

.contact-grid p {
  margin-bottom: 0.5rem;
  font-size: 0.9rem;
}

.contact-grid p:last-child {
  margin-bottom: 0;
}

/* ===== Footer ===== */
.footer {
  background: var(--bg-footer);
  color: var(--text-footer);
  padding: 3.5rem 0 2rem;
  margin-top: 4rem;
  position: relative;
}

.footer::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 2px;
  background: linear-gradient(90deg, transparent, var(--brand-color), transparent);
}

.footer .cols {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
  gap: 2rem;
}

.footer h4 {
  color: #f1f5f9;
  margin-bottom: 1rem;
  font-size: 1rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.footer p, .footer li {
  color: var(--text-footer);
  font-size: 0.85rem;
  margin-bottom: 0.4rem;
}

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

.footer a:hover {
  color: var(--brand-light);
}

.copyright {
  border-top: 1px solid rgba(148, 163, 184, 0.2);
  margin-top: 2.5rem;
  padding-top: 1.8rem;
  text-align: center;
  font-size: 0.8rem;
  color: rgba(148, 163, 184, 0.8);
}

.copyright p {
  color: rgba(148, 163, 184, 0.8);
  font-size: 0.8rem;
  margin-bottom: 0.3rem;
}

/* ===== 返回顶部 ===== */
.back-to-top {
  position: fixed;
  bottom: 28px;
  right: 28px;
  background: var(--brand-color);
  color: #fff;
  width: 46px;
  height: 46px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.3rem;
  box-shadow: 0 6px 20px rgba(225, 29, 72, 0.35);
  cursor: pointer;
  z-index: 999;
  transition: var(--transition);
  opacity: 0.9;
}

.back-to-top:hover {
  transform: translateY(-4px);
  opacity: 1;
  box-shadow: 0 10px 30px rgba(225, 29, 72, 0.5);
}

/* ===== 两列布局 ===== */
.two-col {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 2rem;
}

.three-col {
  display: flex;
  flex-wrap: wrap;
  gap: 2rem;
}

.three-col > div {
  flex: 1 1 220px;
  background: var(--bg-card);
  backdrop-filter: var(--blur);
  -webkit-backdrop-filter: var(--blur);
  padding: 1.5rem;
  border-radius: var(--radius-md);
  border: 1px solid var(--border-light);
  transition: var(--transition);
}

.three-col > div:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-sm);
}

/* ===== 响应式 ===== */
@media (max-width: 1024px) {
  .two-col {
    grid-template-columns: 1fr;
    gap: 1.5rem;
  }
}

@media (max-width: 768px) {
  body {
    font-size: 15px;
  }

  .hero {
    border-radius: 0 0 28px 28px;
  }

  .hero-content {
    flex-direction: column;
    text-align: center;
  }

  .hero-text p {
    margin-left: auto;
    margin-right: auto;
  }

  .hero-cta {
    justify-content: center;
  }

  .hero-visual {
    margin-top: 1rem;
  }

  .section-title {
    font-size: 1.5rem;
    margin-top: 2.5rem;
  }

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

  .back-to-top {
    bottom: 20px;
    right: 20px;
    width: 40px;
    height: 40px;
    font-size: 1.1rem;
  }

  .contact-grid {
    flex-direction: column;
  }
}

@media (max-width: 480px) {
  .logo {
    font-size: 1.2rem;
  }

  .logo svg {
    width: 30px;
    height: 30px;
  }

  .theme-toggle {
    padding: 6px 12px;
    font-size: 0.8rem;
  }

  .btn {
    padding: 0.6rem 1.5rem;
    font-size: 0.85rem;
  }

  .article-item {
    padding: 1rem 0.8rem;
  }
}

/* ===== 滚动动画 ===== */
@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(30px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* 滚动时卡片渐显 */
.card, .article-item, .faq-item, .three-col > div, .contact-grid > div {
  animation: fadeInUp 0.6s ease both;
}

.card:nth-child(1) { animation-delay: 0.05s; }
.card:nth-child(2) { animation-delay: 0.1s; }
.card:nth-child(3) { animation-delay: 0.15s; }
.card:nth-child(4) { animation-delay: 0.2s; }

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

::-webkit-scrollbar-track {
  background: transparent;
}

::-webkit-scrollbar-thumb {
  background: linear-gradient(180deg, var(--brand-color), var(--brand-dark));
  border-radius: 10px;
}

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

/* ===== 选中状态 ===== */
::selection {
  background: var(--brand-color);
  color: white;
}

/* ===== 无障碍焦点状态 ===== */
a:focus-visible, button:focus-visible {
  outline: 2px solid var(--brand-color);
  outline-offset: 3px;
  border-radius: 4px;
}

/* ===== 隐藏元素 ===== */
.hidden {
  display: none !important;
}
```