/* roulang page: index */
:root {
      --primary: #1A5FDC;
      --primary-dark: #1648B0;
      --accent: #7C3AED;
      --accent-light: #A78BFA;
      --bg: #F8FAFC;
      --card-bg: #FFFFFF;
      --dark-bg: #0F172A;
      --darker-bg: #020617;
      --text-heading: #0F172A;
      --text-body: #334155;
      --text-muted: #64748B;
      --text-on-dark: #F1F5F9;
      --border-light: #E2E8F0;
      --shadow-card: 0 4px 24px rgba(0,0,0,0.04);
      --shadow-hover: 0 12px 40px rgba(26,95,220,0.12);
      --radius-lg: 16px;
      --radius-md: 12px;
      --radius-sm: 8px;
      --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
      --font-heading: "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", sans-serif;
      --font-number: "Inter", "SF Pro Text", sans-serif;
    }
    
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    
    html {
      scroll-behavior: smooth;
      font-size: 16px;
    }
    
    body {
      font-family: var(--font-heading);
      background-color: var(--bg);
      color: var(--text-body);
      line-height: 1.75;
      -webkit-font-smoothing: antialiased;
      overflow-x: hidden;
    }
    
    .container {
      max-width: 1280px;
      margin: 0 auto;
      padding: 0 24px;
    }
    
    /* 标题层级 */
    h1 {
      font-size: 3.5rem;
      font-weight: 800;
      color: var(--text-heading);
      line-height: 1.2;
      letter-spacing: -0.5px;
    }
    h2 {
      font-size: 2.25rem;
      font-weight: 800;
      color: var(--text-heading);
      margin-bottom: 16px;
    }
    h3 {
      font-size: 1.25rem;
      font-weight: 700;
      color: var(--text-heading);
    }
    p {
      max-width: 680px;
    }
    
    /* 导航 */
    .navbar {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 1000;
      background: rgba(255,255,255,0.7);
      backdrop-filter: blur(12px);
      -webkit-backdrop-filter: blur(12px);
      border-bottom: 1px solid rgba(0,0,0,0.05);
      transition: var(--transition);
    }
    .navbar.scrolled {
      background: rgba(255,255,255,0.95);
      box-shadow: 0 4px 20px rgba(0,0,0,0.04);
    }
    .nav-container {
      display: flex;
      align-items: center;
      justify-content: space-between;
      max-width: 1280px;
      margin: 0 auto;
      padding: 0 24px;
      height: 72px;
    }
    .logo {
      display: flex;
      align-items: center;
      gap: 10px;
      font-size: 1.5rem;
      font-weight: 800;
      color: var(--primary);
      text-decoration: none;
      letter-spacing: -0.5px;
    }
    .logo-icon {
      font-size: 2rem;
      color: var(--accent);
      transition: transform 0.3s ease;
    }
    .logo:hover .logo-icon {
      transform: rotate(360deg);
    }
    .nav-links {
      display: flex;
      align-items: center;
      gap: 32px;
      list-style: none;
    }
    .nav-links a {
      text-decoration: none;
      color: var(--text-body);
      font-weight: 500;
      font-size: 1rem;
      position: relative;
      padding: 8px 0;
      transition: color 0.2s;
    }
    .nav-links a:hover,
    .nav-links a.active {
      color: var(--primary);
    }
    .nav-links a.active::after {
      content: '';
      position: absolute;
      bottom: 0;
      left: 0;
      width: 100%;
      height: 3px;
      background: var(--accent);
      border-radius: 3px;
    }
    .nav-cta {
      background: linear-gradient(135deg, var(--primary) 0%, #2563EB 100%);
      color: white !important;
      padding: 10px 24px !important;
      border-radius: 30px;
      font-weight: 600;
      transition: var(--transition);
      box-shadow: 0 4px 12px rgba(26,95,220,0.25);
    }
    .nav-cta:hover {
      background: linear-gradient(135deg, var(--primary) 0%, var(--accent) 100%);
      box-shadow: 0 8px 20px rgba(124,58,237,0.4);
      transform: translateY(-2px);
    }
    .menu-toggle {
      display: none;
      background: none;
      border: none;
      font-size: 1.8rem;
      color: var(--text-heading);
      cursor: pointer;
    }
    
    /* 移动端菜单 */
    .mobile-menu {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 100vh;
      background: rgba(255,255,255,0.98);
      backdrop-filter: blur(20px);
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: center;
      gap: 32px;
      z-index: 999;
      transform: translateX(100%);
      transition: transform 0.4s ease;
      list-style: none;
    }
    .mobile-menu.active {
      transform: translateX(0);
    }
    .mobile-menu a {
      font-size: 1.8rem;
      font-weight: 600;
      color: var(--text-heading);
      text-decoration: none;
    }
    
    /* 区块通用 */
    section {
      padding: 100px 0;
    }
    
    /* Hero */
    .hero {
      min-height: 100vh;
      display: flex;
      align-items: center;
      background: linear-gradient(180deg, #F0F4FF 0%, var(--bg) 100%);
      position: relative;
      overflow: hidden;
    }
    .hero .container {
      display: flex;
      align-items: center;
      gap: 60px;
    }
    .hero-content {
      flex: 1;
    }
    .hero-content h1 {
      margin-bottom: 24px;
    }
    .hero-content p {
      font-size: 1.15rem;
      color: var(--text-body);
      margin-bottom: 40px;
    }
    .hero-buttons {
      display: flex;
      gap: 20px;
      flex-wrap: wrap;
    }
    .btn {
      display: inline-flex;
      align-items: center;
      gap: 8px;
      padding: 14px 32px;
      border-radius: var(--radius-md);
      font-weight: 600;
      text-decoration: none;
      transition: var(--transition);
      border: none;
      cursor: pointer;
      font-size: 1rem;
    }
    .btn-primary {
      background: linear-gradient(135deg, var(--primary) 0%, #2563EB 100%);
      color: white;
      box-shadow: 0 8px 20px rgba(26,95,220,0.3);
    }
    .btn-primary:hover {
      background: linear-gradient(135deg, var(--primary) 0%, var(--accent) 100%);
      box-shadow: 0 12px 28px rgba(124,58,237,0.45);
      transform: translateY(-3px);
    }
    .btn-secondary {
      background: white;
      color: var(--primary);
      border: 2px solid var(--primary);
    }
    .btn-secondary:hover {
      background: var(--primary);
      color: white;
    }
    .hero-image {
      flex: 1;
      display: flex;
      justify-content: center;
      animation: float 4s ease-in-out infinite;
    }
    .hero-image img {
      max-width: 100%;
      border-radius: 20px;
      box-shadow: 0 30px 60px rgba(0,0,0,0.1);
      height: auto;
    }
    @keyframes float {
      0%, 100% { transform: translateY(-8px); }
      50% { transform: translateY(0px); }
    }
    
    /* 数据看板 */
    .stats-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 24px;
    }
    .stat-card {
      background: var(--card-bg);
      padding: 32px;
      border-radius: var(--radius-lg);
      box-shadow: var(--shadow-card);
      text-align: center;
      transition: var(--transition);
    }
    .stat-icon {
      font-size: 2rem;
      color: var(--accent);
      margin-bottom: 16px;
    }
    .stat-number {
      font-family: var(--font-number);
      font-size: 3rem;
      font-weight: 800;
      color: var(--primary);
      letter-spacing: -1px;
    }
    .stat-label {
      color: var(--text-muted);
      font-weight: 500;
      margin-top: 8px;
    }
    
    /* 服务矩阵 */
    .services-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }
    .service-card {
      background: var(--card-bg);
      padding: 32px;
      border-radius: var(--radius-lg);
      box-shadow: var(--shadow-card);
      transition: var(--transition);
      display: flex;
      flex-direction: column;
    }
    .service-card:hover {
      transform: translateY(-8px);
      box-shadow: var(--shadow-hover);
    }
    .service-icon {
      width: 56px;
      height: 56px;
      background: #EBF2FF;
      border-radius: var(--radius-md);
      display: flex;
      align-items: center;
      justify-content: center;
      color: var(--primary);
      font-size: 1.8rem;
      margin-bottom: 20px;
      transition: var(--transition);
    }
    .service-card:hover .service-icon {
      background: var(--accent);
      color: white;
    }
    .tags {
      display: flex;
      flex-wrap: wrap;
      gap: 8px;
      margin-top: 16px;
    }
    .tag {
      background: #F1E9FF;
      color: var(--accent);
      padding: 4px 12px;
      border-radius: 20px;
      font-size: 0.8rem;
      font-weight: 600;
    }
    
    /* 对比工具 */
    .comparison-wrapper {
      display: flex;
      gap: 40px;
      align-items: center;
    }
    .comparison-col {
      flex: 1;
      background: var(--card-bg);
      padding: 40px;
      border-radius: var(--radius-lg);
      box-shadow: var(--shadow-card);
    }
    .divider-line {
      width: 2px;
      background: linear-gradient(180deg, var(--primary), var(--accent));
      height: 200px;
      align-self: center;
    }
    .comparison-list {
      list-style: none;
      margin-top: 24px;
    }
    .comparison-list li {
      display: flex;
      align-items: center;
      gap: 12px;
      margin-bottom: 16px;
      font-size: 1.1rem;
    }
    .icon-cross {
      color: #EF4444;
      font-size: 1.4rem;
    }
    .icon-check {
      color: #10B981;
      font-size: 1.4rem;
    }
    
    /* FAQ */
    .faq-list {
      display: flex;
      flex-direction: column;
      gap: 16px;
    }
    .faq-item {
      background: var(--card-bg);
      border: 1px solid var(--border-light);
      border-radius: var(--radius-md);
      overflow: hidden;
      transition: var(--transition);
    }
    .faq-question {
      padding: 20px 24px;
      font-weight: 700;
      display: flex;
      justify-content: space-between;
      align-items: center;
      cursor: pointer;
      background: none;
      border: none;
      width: 100%;
      text-align: left;
      font-size: 1.1rem;
      color: var(--text-heading);
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.4s ease, padding 0.3s ease;
      background: #F8FAFC;
      padding: 0 24px;
      color: var(--text-body);
    }
    .faq-item.active .faq-answer {
      max-height: 200px;
      padding: 20px 24px;
    }
    
    /* 联系表单 */
    .contact-section {
      background: var(--dark-bg);
      color: var(--text-on-dark);
    }
    .contact-card {
      background: var(--card-bg);
      color: var(--text-body);
      border-radius: var(--radius-lg);
      padding: 48px;
      max-width: 600px;
      margin: 0 auto;
    }
    .form-group {
      margin-bottom: 20px;
    }
    .form-group input,
    .form-group textarea {
      width: 100%;
      padding: 14px 16px;
      border: 2px solid var(--border-light);
      border-radius: var(--radius-sm);
      font-family: inherit;
      transition: var(--transition);
      background: #fff;
    }
    .form-group input:focus,
    .form-group textarea:focus {
      outline: none;
      border-color: var(--accent);
      box-shadow: 0 0 0 4px rgba(124,58,237,0.1);
    }
    .btn-submit {
      width: 100%;
      background: linear-gradient(135deg, var(--primary), var(--accent));
      color: white;
      border: none;
      padding: 16px;
      font-weight: 700;
      border-radius: var(--radius-md);
      cursor: pointer;
      transition: var(--transition);
    }
    .btn-submit:hover {
      filter: brightness(1.1);
      box-shadow: 0 8px 24px rgba(124,58,237,0.4);
    }
    
    /* 页脚 */
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 40px;
      padding: 60px 0;
    }
    .footer-links a {
      display: block;
      color: #CBD5E1;
      text-decoration: none;
      margin-bottom: 12px;
      transition: var(--transition);
    }
    .footer-links a:hover {
      color: var(--accent-light);
      transform: translateX(4px);
    }
    .copyright {
      background: var(--darker-bg);
      color: #94A3B8;
      text-align: center;
      padding: 20px 0;
      font-size: 0.9rem;
    }
    
    /* 响应式 */
    @media (max-width: 1024px) {
      h1 { font-size: 2.8rem; }
      .hero .container { flex-direction: column; text-align: center; }
      .hero-image { margin-top: 40px; }
      .stats-grid { grid-template-columns: repeat(2, 1fr); }
      .services-grid { grid-template-columns: repeat(2, 1fr); }
      .comparison-wrapper { flex-direction: column; }
      .divider-line { width: 100%; height: 2px; }
      .footer-grid { grid-template-columns: repeat(2, 1fr); }
    }
    
    @media (max-width: 768px) {
      .nav-links { display: none; }
      .menu-toggle { display: block; }
      .stats-grid { grid-template-columns: 1fr; }
      .services-grid { grid-template-columns: 1fr; }
      h2 { font-size: 1.8rem; }
      h1 { font-size: 2.2rem; }
      section { padding: 70px 0; }
    }