/* roulang page: index */
:root {
      --primary: #1E2F3F;
      --primary-deep: #15212F;
      --accent: #00B894;
      --accent-hover: #00A381;
      --bg: #F8FAFB;
      --card-bg: #FFFFFF;
      --text-main: #1E2F3F;
      --text-body: #475569;
      --text-muted: #94A3B8;
      --border-light: #E2E8F0;
      --shadow-card: 0 1px 3px rgba(0,0,0,0.04), 0 1px 2px rgba(0,0,0,0.06);
      --shadow-hover: 0 4px 12px rgba(0,0,0,0.08);
      --radius-btn: 8px;
      --radius-card: 12px;
      --radius-input: 6px;
      --font-sans: "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", sans-serif;
      --font-number: "Inter", "Segoe UI", system-ui, sans-serif;
    }
    * {
      box-sizing: border-box;
    }
    body {
      margin: 0;
      font-family: var(--font-sans);
      background-color: var(--bg);
      color: var(--text-body);
      line-height: 1.7;
      -webkit-font-smoothing: antialiased;
    }
    h1, h2, h3, h4 {
      color: var(--text-main);
      font-weight: 600;
      letter-spacing: -0.02em;
    }
    h1 { font-size: clamp(2.2rem, 5vw, 3rem); line-height: 1.2; font-weight: 700; }
    h2 { font-size: clamp(1.8rem, 4vw, 2.25rem); line-height: 1.3; }
    h3 { font-size: 1.375rem; line-height: 1.4; }
    .container {
      max-width: 1200px;
      margin-left: auto;
      margin-right: auto;
      padding-left: 1.5rem;
      padding-right: 1.5rem;
    }
    @media (max-width: 768px) {
      .container {
        padding-left: 1rem;
        padding-right: 1rem;
      }
    }
    .nav-blur {
      background: rgba(255,255,255,0.9);
      backdrop-filter: blur(8px);
      -webkit-backdrop-filter: blur(8px);
    }
    .btn-primary {
      background-color: var(--accent);
      color: white;
      border-radius: var(--radius-btn);
      padding: 0.6rem 1.4rem;
      font-weight: 600;
      font-size: 0.9rem;
      transition: all 0.2s ease;
      display: inline-flex;
      align-items: center;
      justify-content: center;
      border: none;
      cursor: pointer;
      font-family: var(--font-number);
      letter-spacing: 0.01em;
    }
    .btn-primary:hover {
      background-color: var(--accent-hover);
      box-shadow: 0 2px 8px rgba(0,184,148,0.2);
    }
    .btn-outline {
      background: transparent;
      border: 1.5px solid var(--primary);
      color: var(--primary);
      border-radius: var(--radius-btn);
      padding: 0.55rem 1.4rem;
      font-weight: 600;
      font-size: 0.9rem;
      transition: all 0.2s ease;
      display: inline-flex;
      align-items: center;
      justify-content: center;
      cursor: pointer;
      font-family: var(--font-number);
    }
    .btn-outline:hover {
      background: rgba(30,47,63,0.05);
    }
    .card {
      background: var(--card-bg);
      border-radius: var(--radius-card);
      box-shadow: var(--shadow-card);
      transition: transform 0.2s ease, box-shadow 0.2s ease;
      overflow: hidden;
    }
    .card:hover {
      transform: translateY(-2px);
      box-shadow: var(--shadow-hover);
    }
    .section-gap {
      padding-top: 5rem;
      padding-bottom: 5rem;
    }
    @media (max-width: 768px) {
      .section-gap {
        padding-top: 3.5rem;
        padding-bottom: 3.5rem;
      }
    }
    .text-accent {
      color: var(--accent);
    }
    .bg-deep {
      background-color: var(--primary-deep);
    }
    .bg-primary {
      background-color: var(--primary);
    }
    input, textarea {
      background: #F8FAFB;
      border: 1px solid #E2E8F0;
      border-radius: var(--radius-input);
      padding: 0.75rem 1rem;
      width: 100%;
      transition: border 0.2s;
      font-family: var(--font-sans);
    }
    input:focus, textarea:focus {
      outline: none;
      border-color: var(--accent);
      box-shadow: 0 0 0 3px rgba(0,184,148,0.15);
    }
    .faq-item {
      border-bottom: 1px solid var(--border-light);
    }
    .faq-question {
      cursor: pointer;
      padding: 1.2rem 0;
      font-weight: 600;
      color: var(--text-main);
      display: flex;
      justify-content: space-between;
      align-items: center;
      transition: color 0.2s;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease, padding 0.3s ease;
      color: var(--text-body);
    }
    .faq-item.active .faq-answer {
      max-height: 200px;
      padding-bottom: 1.2rem;
    }
    .faq-item.active .faq-icon {
      transform: rotate(45deg);
    }
    .faq-icon {
      transition: transform 0.2s ease;
      font-size: 1.4rem;
      color: var(--text-muted);
    }
    .trust-badge {
      display: flex;
      align-items: center;
      gap: 0.5rem;
      font-weight: 500;
      color: var(--text-body);
    }
    @media (max-width: 1023px) {
      .mobile-hidden {
        display: none;
      }
    }
    .hamburger {
      display: none;
      background: none;
      border: none;
      font-size: 1.8rem;
      cursor: pointer;
      color: var(--primary);
    }
    @media (max-width: 768px) {
      .hamburger {
        display: block;
      }
      .desktop-nav {
        display: none;
      }
    }
    .mobile-menu {
      position: absolute;
      top: 64px;
      left: 0;
      right: 0;
      background: white;
      box-shadow: 0 4px 10px rgba(0,0,0,0.05);
      flex-direction: column;
      padding: 1rem;
      display: none;
      z-index: 50;
    }
    .mobile-menu.open {
      display: flex;
    }