/* roulang page: index */
:root {
      /* 主色：沉稳商务蓝，非亮蓝 */
      --primary: #1A5F7A;
      --primary-hover: #134B61;
      --primary-light: rgba(26,95,122,0.08);
      /* 辅色 */
      --secondary: #3D5A6C;
      --accent: #2A9D8F;
      --accent-light: rgba(42,157,143,0.15);
      /* 背景与表面 */
      --body-bg: #F8FAFB;
      --card-bg: #FFFFFF;
      --border-color: #E9ECEF;
      /* 文字层级 */
      --text-primary: #2D3748;
      --text-body: #4A5568;
      --text-muted: #718096;
      --text-light: #A0AEC0;
      /* 圆角与阴影 */
      --radius-sm: 8px;
      --radius-lg: 12px;
      --shadow-card: 0 2px 8px rgba(26,95,122,0.06);
      --shadow-hover: 0 8px 24px rgba(26,95,122,0.12);
      --shadow-hero: 0 20px 40px rgba(26,95,122,0.08);
      /* 间距 */
      --section-gap: 120px;
      --section-gap-tablet: 80px;
      --section-gap-mobile: 60px;
      /* 字体 */
      --font-sans: -apple-system, BlinkMacSystemFont, "PingFang SC", "Microsoft YaHei", "Helvetica Neue", sans-serif;
      --bs-primary: #1A5F7A;
      --bs-primary-rgb: 26,95,122;
      --bs-body-bg: #F8FAFB;
      --bs-body-color: #4A5568;
      --bs-border-radius: 8px;
      --bs-box-shadow: 0 2px 8px rgba(26,95,122,0.06);
    }

    * {
      box-sizing: border-box;
    }

    body {
      font-family: var(--font-sans);
      background-color: var(--body-bg);
      color: var(--text-body);
      line-height: 1.7;
      margin: 0;
      overflow-x: hidden;
    }

    a {
      text-decoration: none;
      color: inherit;
      transition: color 0.2s;
    }

    img {
      max-width: 100%;
      height: auto;
      display: block;
    }

    /* 容器微调 */
    .container {
      max-width: 1140px;
      padding-left: 24px;
      padding-right: 24px;
    }

    /* 按钮体系 */
    .btn {
      border-radius: var(--radius-sm);
      padding: 12px 28px;
      font-weight: 600;
      font-size: 16px;
      letter-spacing: 0.5px;
      min-width: 140px;
      transition: all 0.3s ease;
      border: 1.5px solid transparent;
      box-shadow: none;
    }
    .btn-primary {
      background-color: var(--primary);
      border-color: var(--primary);
      color: white;
    }
    .btn-primary:hover, .btn-primary:focus {
      background-color: var(--primary-hover);
      border-color: var(--primary-hover);
      box-shadow: var(--shadow-hover);
      color: white;
    }
    .btn-outline-primary {
      background: transparent;
      border: 1.5px solid var(--primary);
      color: var(--primary);
    }
    .btn-outline-primary:hover {
      background-color: var(--primary-light);
      color: var(--primary);
    }
    .btn:focus {
      box-shadow: 0 0 0 3px rgba(26,95,122,0.25);
    }

    /* 吸顶导航 */
    .navbar {
      padding: 0;
      transition: background 0.3s, box-shadow 0.3s;
    }
    .navbar.sticky-active {
      background: rgba(255,255,255,0.92);
      backdrop-filter: blur(12px);
      box-shadow: 0 2px 8px rgba(0,0,0,0.02);
      border-bottom: 1px solid var(--border-color);
    }
    .brand-row {
      height: 56px;
      display: flex;
      align-items: center;
    }
    .navbar-brand {
      font-weight: 700;
      font-size: 20px;
      color: var(--primary) !important;
      display: flex;
      align-items: center;
      gap: 8px;
    }
    .logo-icon {
      font-size: 28px;
      color: var(--primary);
    }
    .navbar-nav .nav-link {
      font-size: 15px;
      color: var(--text-body) !important;
      padding: 0 16px;
      font-weight: 500;
      position: relative;
    }
    .navbar-nav .nav-link:hover,
    .navbar-nav .nav-link.active {
      color: var(--primary) !important;
    }
    .navbar-nav .nav-link.active::after {
      content: '';
      position: absolute;
      bottom: -2px;
      left: 16px;
      right: 16px;
      height: 2px;
      background: var(--primary);
    }
    .search-placeholder {
      background: #F1F3F5;
      border-radius: 20px;
      padding: 6px 16px;
      font-size: 13px;
      color: var(--text-muted);
      display: flex;
      align-items: center;
      gap: 8px;
    }
    .hot-tag {
      background: var(--border-color);
      border-radius: 20px;
      padding: 2px 12px;
      font-size: 12px;
      color: var(--text-muted);
    }
    .navbar-toggler {
      border: none;
      color: var(--primary);
    }

    /* Hero区域 */
    .hero-section {
      min-height: 520px;
      display: flex;
      align-items: center;
      background-color: var(--body-bg);
      background-image: radial-gradient(circle at 20% 30%, rgba(26,95,122,0.02) 0%, transparent 35%);
      position: relative;
    }
    .hero-title {
      font-size: 40px;
      font-weight: 600;
      line-height: 1.3;
      color: var(--text-primary);
      max-width: 540px;
    }
    .hero-sub {
      font-size: 18px;
      color: var(--text-body);
      max-width: 500px;
    }
    .hero-img {
      max-height: 400px;
      filter: drop-shadow(0 12px 16px rgba(26,95,122,0.1));
    }
    .trust-signal {
      font-size: 14px;
      color: var(--text-muted);
      display: flex;
      align-items: center;
      gap: 8px;
    }

    /* 板块标题 */
    .section-title {
      font-size: 32px;
      font-weight: 600;
      color: var(--text-primary);
      margin-bottom: 16px;
    }
    .section-desc {
      color: var(--text-muted);
      max-width: 680px;
      margin-bottom: 48px;
      font-size: 16px;
    }

    /* 卡片体系 */
    .card-custom {
      background: var(--card-bg);
      border-radius: var(--radius-lg);
      box-shadow: var(--shadow-card);
      transition: all 0.3s ease;
      border: none;
      height: 100%;
    }
    .card-custom:hover {
      box-shadow: var(--shadow-hover);
      transform: translateY(-2px);
    }
    .card-lg {
      padding: 32px;
    }
    .card-sm {
      padding: 24px;
    }
    .icon-accent {
      color: var(--accent);
      font-size: 28px;
      margin-bottom: 16px;
    }

    /* 非对称优势布局 */
    .feature-large .card-custom {
      background: linear-gradient(135deg, #ffffff 0%, #F4F8FA 100%);
    }

    /* 产品网格 */
    .product-card ul {
      list-style: none;
      padding-left: 0;
      color: var(--text-body);
    }
    .product-card li::before {
      content: "✓";
      color: var(--accent);
      margin-right: 8px;
      font-weight: bold;
    }

    /* 步骤条 */
    .step-item {
      position: relative;
      text-align: center;
      flex: 1;
    }
    .step-number {
      font-size: 48px;
      font-weight: 700;
      color: rgba(26,95,122,0.1);
      line-height: 1;
    }
    .step-title {
      font-weight: 600;
      font-size: 18px;
      margin: 8px 0 4px;
    }
    .step-desc {
      color: var(--text-muted);
      font-size: 14px;
    }
    .step-connector {
      border-top: 2px dashed var(--accent);
      flex: 0.5;
      align-self: center;
      margin: 0 8px;
    }

    /* 证言区 */
    .testimonial-bg {
      background: #F0F4F7;
    }
    .testimonial-card {
      background: white;
      border-radius: var(--radius-lg);
      padding: 28px;
      box-shadow: var(--shadow-card);
      display: flex;
      gap: 20px;
      align-items: flex-start;
    }
    .avatar-placeholder {
      width: 56px;
      height: 56px;
      border-radius: 50%;
      background: #E9ECEF;
      object-fit: cover;
    }
    .quote-text {
      font-style: italic;
      font-size: 18px;
      color: var(--text-primary);
      border-left: 3px solid var(--accent);
      padding-left: 16px;
      margin-bottom: 12px;
    }

    /* FAQ手风琴 */
    .accordion-button {
      background: white;
      color: var(--text-primary);
      font-weight: 500;
      box-shadow: none !important;
      border: none;
    }
    .accordion-button:not(.collapsed) {
      background: #F8FAFB;
      color: var(--primary);
      font-weight: 600;
    }
    .accordion-item {
      border: none;
      border-bottom: 1px solid var(--border-color);
    }
    .accordion-button::after {
      color: var(--accent);
    }

    /* CTA渐变区 */
    .cta-gradient {
      background: linear-gradient(120deg, #EFF6F9 0%, #FFFFFF 100%);
    }
    .form-control {
      height: 48px;
      border-radius: var(--radius-sm);
      border: 1px solid #CBD5E0;
    }
    .form-control:focus {
      border-color: var(--primary);
      box-shadow: 0 0 0 3px rgba(26,95,122,0.15);
    }

    /* 页脚 */
    .footer-dark {
      background: #1A202C;
      color: #CBD5E0;
      padding: 48px 0 0;
    }
    .footer-dark h5 {
      color: white;
      font-weight: 600;
      font-size: 16px;
      margin-bottom: 16px;
      border-bottom: 2px solid var(--accent);
      display: inline-block;
      padding-bottom: 6px;
    }
    .footer-dark a {
      color: #A0AEC0;
      font-size: 14px;
    }
    .footer-dark a:hover {
      color: white;
    }
    .copyright {
      background: #171923;
      font-size: 13px;
      color: #718096;
    }

    /* 响应式 */
    @media (max-width: 992px) {
      .hero-title {
        font-size: 32px;
      }
      .section-title {
        font-size: 28px;
      }
      .step-connector {
        display: none;
      }
    }
    @media (max-width: 768px) {
      .hero-title {
        font-size: 28px;
      }
      .section-title {
        font-size: 24px;
      }
      .hero-section {
        min-height: auto;
        padding: 40px 0;
      }
      .testimonial-card {
        flex-direction: column;
      }
      .footer-dark .col-md-3 {
        margin-bottom: 30px;
      }
    }
    @media (max-width: 576px) {
      .btn {
        min-width: 120px;
        padding: 10px 20px;
      }
    }