/* roulang page: index */
:root {
      --primary: #1A5F7A;
      --primary-dark: #134B60;
      --accent: #0D9488;
      --accent-light: #14B8A6;
      --bg: #F8FAFC;
      --card-bg: #FFFFFF;
      --text-primary: #0F172A;
      --text-secondary: #475569;
      --text-muted: #94A3B8;
      --cta: #EAB308;
      --cta-hover: #CA8A04;
      --success: #10B981;
      --danger: #EF4444;
      --border: #E2E8F0;
      --shadow-sm: 0 1px 3px rgba(0,0,0,0.04), 0 4px 12px rgba(0,0,0,0.06);
      --shadow-hover: 0 2px 8px rgba(0,0,0,0.06), 0 8px 24px rgba(0,0,0,0.10);
      --radius-lg: 12px;
      --radius-md: 8px;
      --radius-sm: 6px;
      --transition: 0.25s ease;
    }
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    body {
      font-family: "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", "Noto Sans SC", system-ui, -apple-system, sans-serif;
      background-color: var(--bg);
      color: var(--text-primary);
      line-height: 1.7;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
    }
    .container {
      width: 100%;
      max-width: 1200px;
      margin: 0 auto;
      padding: 0 24px;
    }
    h1, h2, h3 {
      font-weight: 600;
      line-height: 1.3;
    }
    h1 {
      font-size: 48px;
      letter-spacing: -0.5px;
      font-weight: 700;
    }
    h2 {
      font-size: 32px;
      margin-bottom: 16px;
    }
    h3 {
      font-size: 18px;
      line-height: 1.4;
    }
    p {
      color: var(--text-secondary);
      max-width: 680px;
    }
    a {
      text-decoration: none;
      color: inherit;
    }
    img {
      max-width: 100%;
      height: auto;
      display: block;
    }
    button, input, textarea {
      font-family: inherit;
    }
    /* 导航 */
    .header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      background: #FFFFFF;
      box-shadow: 0 1px 0 var(--border);
      z-index: 1000;
      height: 64px;
      display: flex;
      align-items: center;
    }
    .header .container {
      display: flex;
      justify-content: space-between;
      align-items: center;
    }
    .logo {
      font-size: 20px;
      font-weight: 700;
      color: var(--primary);
      white-space: nowrap;
      display: flex;
      align-items: center;
      gap: 8px;
    }
    .logo i {
      font-size: 24px;
      color: var(--accent);
    }
    .nav-menu {
      display: flex;
      gap: 32px;
      align-items: center;
    }
    .nav-link {
      font-size: 15px;
      font-weight: 500;
      color: var(--text-secondary);
      transition: color var(--transition);
      position: relative;
      padding: 4px 0;
    }
    .nav-link:hover, .nav-link.active {
      color: var(--primary);
    }
    .nav-link.active::after {
      content: '';
      position: absolute;
      bottom: -2px;
      left: 0;
      width: 100%;
      height: 2px;
      background: var(--primary);
    }
    .btn-cta-sm {
      background: var(--cta);
      color: #FFFFFF;
      border: none;
      padding: 10px 20px;
      border-radius: var(--radius-md);
      font-weight: 600;
      font-size: 14px;
      transition: background var(--transition);
      white-space: nowrap;
    }
    .btn-cta-sm:hover {
      background: var(--cta-hover);
    }
    .hamburger {
      display: none;
      background: none;
      border: none;
      font-size: 24px;
      color: var(--text-primary);
      cursor: pointer;
    }
    .mobile-menu {
      display: none;
      position: fixed;
      top: 64px;
      left: 0;
      width: 100%;
      background: #FFFFFF;
      flex-direction: column;
      padding: 24px 0;
      box-shadow: 0 8px 20px rgba(0,0,0,0.1);
      z-index: 999;
      animation: fadeIn 0.2s ease;
    }
    .mobile-menu a {
      display: block;
      padding: 14px 32px;
      font-weight: 500;
      color: var(--text-primary);
    }
    @keyframes fadeIn {
      from { opacity: 0; transform: translateY(-10px); }
      to { opacity: 1; transform: translateY(0); }
    }
    /* 按钮系统 */
    .btn-primary {
      background: var(--cta);
      color: #fff;
      padding: 14px 28px;
      border-radius: var(--radius-md);
      font-weight: 600;
      border: none;
      cursor: pointer;
      transition: background var(--transition);
      display: inline-block;
    }
    .btn-primary:hover { background: var(--cta-hover); }
    .btn-outline {
      background: transparent;
      border: 2px solid white;
      color: white;
      padding: 12px 28px;
      border-radius: var(--radius-md);
      font-weight: 600;
      transition: all var(--transition);
      display: inline-block;
    }
    .btn-outline:hover {
      background: white;
      color: var(--primary);
    }
    .btn-text {
      color: var(--accent);
      font-weight: 600;
      border-bottom: 2px solid transparent;
      transition: border var(--transition);
      padding-bottom: 2px;
      display: inline-block;
    }
    .btn-text:hover { border-bottom-color: var(--accent); }
    /* Hero */
    .hero {
      background: url('/assets/images/backpic/back-1.webp') center/cover no-repeat;
      position: relative;
      min-height: 85vh;
      display: flex;
      align-items: center;
      justify-content: center;
      text-align: center;
      color: white;
    }
    .hero::before {
      content: '';
      position: absolute;
      inset: 0;
      background: linear-gradient(135deg, rgba(26,95,122,0.75) 0%, rgba(13,148,136,0.4) 100%);
    }
    .hero-content {
      position: relative;
      z-index: 2;
      max-width: 800px;
      padding: 0 24px;
    }
    .hero h1 {
      color: white;
      text-shadow: 0 2px 8px rgba(0,0,0,0.3);
      margin-bottom: 24px;
    }
    .hero .subtitle {
      font-size: 18px;
      opacity: 0.95;
      margin-bottom: 32px;
      max-width: 600px;
      margin-left: auto;
      margin-right: auto;
    }
    .hero-buttons {
      display: flex;
      gap: 16px;
      justify-content: center;
      flex-wrap: wrap;
    }
    /* 板块通用 */
    section {
      padding: 100px 0;
    }
    .section-title {
      text-align: center;
      margin-bottom: 48px;
    }
    .section-title h2 {
      margin-bottom: 8px;
    }
    .subheading {
      color: var(--text-secondary);
      font-size: 16px;
    }
    /* 数据看板 */
    .stats-grid {
      display: grid;
      grid-template-columns: repeat(4,1fr);
      gap: 24px;
      background: #F1F5F9;
      border-radius: var(--radius-lg);
      padding: 40px 24px;
    }
    .stat-item {
      text-align: center;
    }
    .stat-number {
      font-size: 40px;
      font-weight: 700;
      color: var(--accent);
    }
    .stat-label {
      font-size: 13px;
      color: var(--text-secondary);
      margin-top: 8px;
    }
    /* 服务卡片 */
    .services-grid {
      display: grid;
      grid-template-columns: repeat(3,1fr);
      gap: 24px;
    }
    .service-card {
      background: var(--card-bg);
      border-radius: var(--radius-lg);
      box-shadow: var(--shadow-sm);
      padding: 28px;
      transition: all var(--transition);
      border-top: 4px solid var(--accent);
      display: flex;
      flex-direction: column;
    }
    .service-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-hover);
    }
    .card-icon {
      width: 64px;
      height: 64px;
      background: #E6F7F5;
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      margin-bottom: 20px;
      color: var(--accent);
      font-size: 28px;
    }
    .service-card h3 {
      margin-bottom: 12px;
    }
    .service-card p {
      flex: 1;
      margin-bottom: 16px;
    }
    /* 对比区 */
    .compare-row {
      display: grid;
      grid-template-columns: 1fr auto 1fr;
      gap: 24px;
      align-items: center;
    }
    .vs-badge {
      background: white;
      border-radius: 50%;
      width: 60px;
      height: 60px;
      display: flex;
      align-items: center;
      justify-content: center;
      font-weight: 700;
      color: var(--primary);
      box-shadow: var(--shadow-sm);
      font-size: 18px;
      margin: 0 auto;
    }
    .compare-card {
      padding: 32px;
      border-radius: var(--radius-lg);
    }
    .compare-card.negative {
      background: #FEF2F2;
      border: 1px solid #FECACA;
    }
    .compare-card.positive {
      background: #F0FDF4;
      border: 1px solid #A7F3D0;
    }
    .compare-list {
      list-style: none;
      margin-top: 20px;
    }
    .compare-list li {
      margin-bottom: 14px;
      display: flex;
      align-items: center;
      gap: 12px;
    }
    /* FAQ */
    .faq-list {
      max-width: 800px;
      margin: 0 auto;
    }
    .faq-item {
      border-bottom: 1px solid var(--border);
      margin-bottom: 8px;
    }
    .faq-question {
      width: 100%;
      background: none;
      border: none;
      padding: 20px 0;
      font-size: 18px;
      font-weight: 600;
      display: flex;
      justify-content: space-between;
      cursor: pointer;
      color: var(--text-primary);
      text-align: left;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease;
      color: var(--text-secondary);
    }
    .faq-answer.open {
      max-height: 200px;
      padding-bottom: 16px;
    }
    /* CTA块 */
    .cta-block {
      background: var(--primary);
      padding: 80px 0;
      color: white;
    }
    .cta-form {
      display: grid;
      grid-template-columns: 1fr 1fr auto;
      gap: 16px;
      max-width: 800px;
      margin: 32px auto 0;
    }
    .cta-form input {
      padding: 14px;
      border-radius: var(--radius-md);
      border: 1px solid #CBD5E1;
      background: white;
    }
    .form-note {
      font-size: 13px;
      opacity: 0.8;
      margin-top: 16px;
      text-align: center;
    }
    /* 页脚 */
    .footer {
      background: #0F172A;
      color: #94A3B8;
      padding: 60px 0 20px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 32px;
    }
    .footer a {
      color: #CBD5E1;
    }
    .copyright {
      border-top: 1px solid #334155;
      margin-top: 40px;
      padding-top: 20px;
      text-align: center;
      font-size: 14px;
    }
    /* 响应式 */
    @media (max-width: 1024px) {
      .services-grid { grid-template-columns: repeat(2,1fr); }
      .compare-row { grid-template-columns: 1fr; }
      .vs-badge { margin: 16px auto; }
    }
    @media (max-width: 768px) {
      .nav-menu { display: none; }
      .hamburger { display: block; }
      .mobile-menu.active { display: flex; }
      h1 { font-size: 36px; }
      h2 { font-size: 28px; }
      .stats-grid { grid-template-columns: repeat(2,1fr); }
      .services-grid { grid-template-columns: 1fr; }
      .cta-form { grid-template-columns: 1fr; }
      .footer-grid { grid-template-columns: 1fr 1fr; }
      section { padding: 64px 0; }
    }
    @media (max-width: 480px) {
      h1 { font-size: 28px; }
      .hero-buttons { flex-direction: column; align-items: center; }
      .stats-grid { grid-template-columns: 1fr; }
    }