/* roulang page: index */
:root {
      --primary: #1E3A8A;
      --primary-hover: #1D4ED8;
      --secondary: #0D9488;
      --bg-slate: #F8FAFC;
      --bg-alt: #F1F5F9;
      --dark-navy: #0F172A;
      --text-main: #0F172A;
      --text-muted: #334155;
      --text-light: #64748B;
      --border-color: #E2E8F0;
      --shadow-card: 0 4px 20px -2px rgba(15, 23, 42, 0.05);
      --radius-box: 14px;
    }
    html {
      scroll-behavior: smooth;
      font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
    }
    body {
      color: var(--text-main);
      background-color: #ffffff;
      line-height: 1.68;
    }
    .hero-bg-overlay {
      background: linear-gradient(135deg, rgba(15, 23, 42, 0.88) 0%, rgba(30, 58, 138, 0.82) 100%), url('/assets/images/ef9ed84550319506.webp') center/cover no-repeat;
    }
    .feature-card-hover {
      transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    }
    .feature-card-hover:hover {
      transform: translateY(-4px);
      box-shadow: 0 12px 28px -4px rgba(30, 58, 138, 0.12);
    }
    .custom-gradient-banner {
      background: linear-gradient(90deg, #1E3A8A 0%, #0F172A 100%);
    }
    .faq-content {
      transition: max-height 0.3s ease, opacity 0.3s ease;
    }