/* roulang page: index */
:root {
      --primary-deep: #0B0E14;
      --accent-gold: #D4AF37;
      --accent-gold-light: #E5C158;
      --bg-light: #FAFAFA;
      --white: #FFFFFF;
      --card-bg: #FFFFFF;
      --text-dark: #1A1F2B;
      --text-body: #4A4A4A;
      --text-muted: #8C8C8C;
      --border-light: #E5E5E5;
      --shadow-sm: 0 2px 16px rgba(0,0,0,0.06);
      --shadow-md: 0 8px 30px rgba(0,0,0,0.12);
      --radius-card: 12px;
      --radius-btn: 8px;
      --font-sans: 'Noto Sans SC', system-ui, -apple-system, sans-serif;
      --transition-smooth: 0.3s cubic-bezier(0.25, 0.46, 0.45, 0.94);
    }
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    body {
      font-family: var(--font-sans);
      background-color: var(--bg-light);
      color: var(--text-body);
      line-height: 1.7;
      -webkit-font-smoothing: antialiased;
    }
    .container {
      max-width: 1200px;
      margin: 0 auto;
      padding: 0 24px;
    }
    h1, h2, h3 {
      font-weight: 700;
      color: var(--text-dark);
    }
    h1 {
      font-size: 56px;
      line-height: 1.2;
    }
    h2 {
      font-size: 40px;
      line-height: 1.3;
      margin-bottom: 16px;
    }
    h3 {
      font-size: 20px;
      line-height: 1.4;
      margin-bottom: 8px;
    }
    a {
      text-decoration: none;
      color: inherit;
    }
    img {
      max-width: 100%;
      display: block;
    }
    button, .btn {
      cursor: pointer;
      font-family: inherit;
    }
    /* 导航 */
    .header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 1000;
      transition: background-color 0.3s, box-shadow 0.3s;
      padding: 16px 0;
    }
    .header.scrolled {
      background-color: var(--white);
      box-shadow: 0 1px 8px rgba(0,0,0,0.05);
    }
    .nav-container {
      display: flex;
      align-items: center;
      justify-content: space-between;
      max-width: 1200px;
      margin: 0 auto;
      padding: 0 24px;
    }
    .logo {
      font-weight: 700;
      font-size: 24px;
      letter-spacing: 1px;
      color: var(--white);
      transition: color 0.3s;
    }
    .header.scrolled .logo {
      color: var(--primary-deep);
    }
    .nav-links {
      display: flex;
      gap: 32px;
      align-items: center;
    }
    .nav-links a {
      font-size: 15px;
      font-weight: 500;
      color: rgba(255,255,255,0.9);
      position: relative;
      padding: 4px 0;
      transition: color 0.2s;
    }
    .header.scrolled .nav-links a {
      color: var(--text-dark);
    }
    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: 0;
      left: 0;
      width: 0;
      height: 2px;
      background-color: var(--accent-gold);
      transition: width 0.25s ease;
    }
    .nav-links a:hover {
      color: var(--accent-gold);
    }
    .nav-links a:hover::after {
      width: 100%;
    }
    .btn-primary {
      background-color: var(--accent-gold);
      color: var(--primary-deep);
      font-weight: 700;
      padding: 12px 28px;
      border-radius: var(--radius-btn);
      border: none;
      font-size: 16px;
      transition: background-color 0.25s, transform 0.2s;
      display: inline-block;
    }
    .btn-primary:hover {
      background-color: var(--accent-gold-light);
      transform: translateY(-1px);
    }
    .btn-outline {
      background: transparent;
      border: 2px solid var(--accent-gold);
      color: var(--accent-gold);
      font-weight: 700;
      padding: 12px 28px;
      border-radius: var(--radius-btn);
      font-size: 16px;
      transition: all 0.25s;
      display: inline-block;
    }
    .btn-outline:hover {
      background-color: rgba(212, 175, 55, 0.1);
      color: var(--accent-gold);
    }
    .mobile-menu-btn {
      display: none;
      background: none;
      border: none;
      font-size: 28px;
      color: var(--white);
    }
    .header.scrolled .mobile-menu-btn {
      color: var(--primary-deep);
    }
    /* 移动端底部导航 */
    .mobile-bottom-nav {
      display: none;
    }
    /* Hero */
    .hero {
      background: linear-gradient(135deg, #0B0E14 0%, #1A1F2B 100%);
      min-height: 90vh;
      display: flex;
      align-items: center;
      justify-content: center;
      text-align: center;
      position: relative;
      overflow: hidden;
      padding: 160px 24px 120px;
    }
    .particles {
      position: absolute;
      top: 0;
      left: 0;
      width: 100%;
      height: 100%;
      pointer-events: none;
    }
    .particle {
      position: absolute;
      background: var(--accent-gold);
      border-radius: 50%;
      opacity: 0.3;
      animation: float 20s infinite alternate ease-in-out;
    }
    @keyframes float {
      0% { transform: translateY(0px) translateX(0); }
      100% { transform: translateY(-40px) translateX(20px); }
    }
    .hero-content {
      position: relative;
      z-index: 2;
      max-width: 800px;
    }
    .hero h1 {
      color: var(--white);
      margin-bottom: 24px;
    }
    .hero .subtitle {
      font-size: 18px;
      color: rgba(255,255,255,0.8);
      max-width: 600px;
      margin: 0 auto 40px;
      font-weight: 400;
    }
    .hero-actions {
      display: flex;
      gap: 16px;
      justify-content: center;
      flex-wrap: wrap;
    }
    .hero-visual {
      margin-top: 60px;
      max-width: 700px;
      margin-left: auto;
      margin-right: auto;
      animation: subtleFloat 5s infinite alternate;
    }
    @keyframes subtleFloat {
      0% { transform: translateY(0); }
      100% { transform: translateY(-10px); }
    }
    /* 通用区块 */
    section {
      padding: 100px 0;
    }
    .section-title {
      text-align: center;
      margin-bottom: 60px;
    }
    .section-title h2 {
      margin-bottom: 12px;
    }
    .section-title p {
      color: var(--text-muted);
      max-width: 600px;
      margin: 0 auto;
    }
    /* 功能卡片 */
    .features-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
      row-gap: 48px;
    }
    .feature-card {
      background: var(--card-bg);
      border-radius: var(--radius-card);
      padding: 32px;
      box-shadow: var(--shadow-sm);
      transition: var(--transition-smooth);
      display: flex;
      gap: 20px;
      align-items: flex-start;
    }
    .feature-card:hover {
      box-shadow: var(--shadow-md);
      transform: translateY(-4px);
      border-top: 3px solid var(--accent-gold);
    }
    .feature-icon {
      font-size: 40px;
      color: var(--accent-gold);
      flex-shrink: 0;
    }
    .feature-text h3 {
      margin-bottom: 8px;
    }
    .feature-text p {
      color: var(--text-body);
      font-size: 15px;
    }
    /* 场景 */
    .scenarios-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }
    .scenario-card {
      position: relative;
      border-radius: var(--radius-card);
      overflow: hidden;
      height: 320px;
      background-size: cover;
      background-position: center;
      transition: transform 0.5s ease;
    }
    .scenario-card:hover {
      transform: scale(1.03);
    }
    .scenario-overlay {
      position: absolute;
      bottom: 0;
      left: 0;
      width: 100%;
      padding: 30px;
      background: linear-gradient(to top, rgba(0,0,0,0.8), transparent);
      color: white;
      text-align: left;
    }
    .scenario-overlay h3 {
      color: white;
      margin-bottom: 4px;
    }
    /* 案例 */
    .cases-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }
    .case-card {
      background: #F5F5F5;
      border-radius: var(--radius-card);
      padding: 28px;
      display: flex;
      gap: 24px;
      align-items: center;
      transition: var(--transition-smooth);
    }
    .case-card:hover {
      background: white;
      box-shadow: var(--shadow-sm);
    }
    .case-number {
      font-family: 'DIN Alternate', 'Noto Sans SC', sans-serif;
      font-weight: 700;
      font-size: 42px;
      color: var(--accent-gold);
    }
    .case-content p {
      font-style: italic;
      margin-bottom: 8px;
    }
    .case-tag {
      color: var(--text-muted);
      font-size: 14px;
    }
    /* 价格 */
    .pricing-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }
    .pricing-card {
      background: var(--white);
      border-radius: var(--radius-card);
      padding: 40px 28px;
      text-align: center;
      border: 1px solid var(--border-light);
      transition: var(--transition-smooth);
      position: relative;
    }
    .pricing-card.featured {
      border: 2px solid var(--accent-gold);
    }
    .badge {
      background: var(--accent-gold);
      color: var(--white);
      font-size: 13px;
      padding: 4px 16px;
      border-radius: 20px;
      display: inline-block;
      margin-bottom: 16px;
      font-weight: 500;
    }
    .price {
      font-size: 40px;
      font-weight: 700;
      color: var(--accent-gold);
      margin: 20px 0;
    }
    .feature-list {
      list-style: none;
      text-align: left;
      margin: 24px 0;
    }
    .feature-list li {
      margin-bottom: 12px;
      color: var(--text-body);
    }
    .feature-list i {
      color: var(--accent-gold);
      margin-right: 8px;
    }
    /* FAQ */
    .faq-list {
      max-width: 800px;
      margin: 0 auto;
    }
    .faq-item {
      border-bottom: 1px solid #e0e0e0;
      padding: 20px 0;
    }
    .faq-question {
      display: flex;
      justify-content: space-between;
      align-items: center;
      cursor: pointer;
      font-weight: 700;
      font-size: 18px;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.4s ease;
      color: var(--text-body);
      margin-top: 8px;
    }
    .faq-item.active .faq-answer {
      max-height: 200px;
    }
    .faq-icon {
      color: var(--accent-gold);
      transition: transform 0.3s;
    }
    .faq-item.active .faq-icon {
      transform: rotate(45deg);
    }
    /* Footer CTA */
    .footer-cta {
      background: var(--primary-deep);
      color: white;
      text-align: center;
      padding: 80px 24px;
    }
    .footer-cta h2 {
      color: white;
    }
    .copyright {
      margin-top: 40px;
      color: var(--text-muted);
      font-size: 14px;
    }
    /* 响应式 */
    @media (max-width: 1024px) {
      h1 { font-size: 44px; }
      h2 { font-size: 34px; }
    }
    @media (max-width: 768px) {
      .nav-links { display: none; }
      .mobile-menu-btn { display: block; }
      .header.scrolled .mobile-menu-btn { color: var(--primary-deep); }
      .mobile-bottom-nav {
        display: flex;
        position: fixed;
        bottom: 0;
        left: 0;
        width: 100%;
        background: white;
        box-shadow: 0 -2px 12px rgba(0,0,0,0.06);
        justify-content: space-around;
        padding: 10px 0;
        z-index: 999;
      }
      .mobile-bottom-nav a {
        font-size: 12px;
        color: var(--text-body);
        display: flex;
        flex-direction: column;
        align-items: center;
        gap: 4px;
        font-weight: 500;
      }
      .hero {
        padding: 120px 24px 80px;
      }
      h1 { font-size: 36px; }
      h2 { font-size: 28px; }
      .features-grid, .scenarios-grid, .cases-grid, .pricing-grid {
        grid-template-columns: 1fr;
      }
      .feature-card {
        flex-direction: column;
        align-items: flex-start;
      }
      section {
        padding: 60px 0;
      }
    }
    @media (max-width: 520px) {
      .container { padding: 0 16px; }
    }