/* roulang page: index */
:root {
      --primary: #1A3C5E;
      --primary-hover: #15304D;
      --secondary: #C49A6C;
      --secondary-hover: #B0865A;
      --body-bg: #FAF9F6;
      --card-bg: #FFFFFF;
      --text-main: #2C2C2C;
      --text-muted: #5A5A5A;
      --border-light: #E8E2D9;
      --border-input: #D9D2C7;
      --footer-bg: #1A2D3E;
      --footer-text: #B0BEC5;
      --shadow-sm: 0 2px 16px rgba(26, 60, 94, 0.06);
      --shadow-hover: 0 8px 28px rgba(26, 60, 94, 0.12);
      --radius-card: 12px;
      --radius-btn: 8px;
      --radius-input: 6px;
      --transition: all 0.25s ease;
    }

    * {
      box-sizing: border-box;
    }

    body {
      background-color: var(--body-bg);
      color: var(--text-main);
      font-family: -apple-system, BlinkMacSystemFont, "PingFang SC", "Microsoft YaHei", "Helvetica Neue", sans-serif;
      line-height: 1.75;
      margin: 0;
      padding: 0;
    }

    /* 容器微调 */
    .container-custom {
      max-width: 1200px;
      margin: 0 auto;
      padding-left: 20px;
      padding-right: 20px;
    }

    /* 导航栏 */
    .navbar-custom {
      background: rgba(255, 255, 255, 0.92);
      backdrop-filter: blur(12px);
      border-bottom: 1px solid var(--border-light);
      padding: 0.8rem 0;
      transition: var(--transition);
    }
    .navbar-custom.scrolled {
      box-shadow: 0 2px 12px rgba(0,0,0,0.04);
    }
    .navbar-brand {
      font-weight: 700;
      font-size: 1.5rem;
      color: var(--primary) !important;
      letter-spacing: 1px;
    }
    .navbar-brand small {
      font-size: 0.75rem;
      font-weight: 400;
      color: var(--text-muted);
      margin-left: 0.5rem;
      letter-spacing: 0.3px;
    }
    .nav-link {
      color: var(--text-main) !important;
      font-weight: 500;
      margin: 0 0.3rem;
      padding: 0.5rem 0.8rem !important;
      border-radius: 6px;
      transition: var(--transition);
      position: relative;
    }
    .nav-link:hover, .nav-link.active {
      color: var(--primary) !important;
    }
    .nav-link.active::after {
      content: '';
      position: absolute;
      bottom: 2px;
      left: 0.8rem;
      right: 0.8rem;
      height: 3px;
      background-color: var(--primary);
      border-radius: 3px;
    }
    .btn-nav {
      background-color: var(--primary);
      color: white !important;
      border-radius: var(--radius-btn);
      padding: 0.5rem 1.5rem !important;
      font-weight: 600;
      border: none;
      transition: var(--transition);
    }
    .btn-nav:hover {
      background-color: var(--primary-hover);
      transform: translateY(-2px);
      box-shadow: var(--shadow-hover);
    }

    /* 按钮全局 */
    .btn-primary-custom {
      background-color: var(--primary);
      border: none;
      color: white;
      font-weight: 600;
      padding: 0.75rem 2rem;
      border-radius: var(--radius-btn);
      transition: var(--transition);
      display: inline-block;
      text-decoration: none;
    }
    .btn-primary-custom:hover {
      background-color: var(--primary-hover);
      transform: translateY(-2px);
      box-shadow: var(--shadow-hover);
      color: white;
    }
    .btn-outline-custom {
      background: transparent;
      border: 1.5px solid var(--primary);
      color: var(--primary);
      font-weight: 600;
      padding: 0.75rem 2rem;
      border-radius: var(--radius-btn);
      transition: var(--transition);
      display: inline-block;
      text-decoration: none;
    }
    .btn-outline-custom:hover {
      background-color: rgba(26, 60, 94, 0.08);
      color: var(--primary);
      transform: translateY(-2px);
    }

    /* Hero */
    .hero-section {
      padding: 120px 0 100px;
      background-color: var(--body-bg);
    }
    .hero-title {
      font-size: 2.8rem;
      font-weight: 700;
      color: var(--primary);
      letter-spacing: -0.5px;
      line-height: 1.25;
    }
    .hero-sub {
      font-size: 1.15rem;
      color: var(--text-muted);
      max-width: 500px;
      margin: 1.5rem 0 2rem;
    }
    .hero-image {
      border-radius: 16px;
      box-shadow: var(--shadow-sm);
      width: 100%;
      height: auto;
    }

    /* 区块标题 */
    .section-title {
      font-size: 2rem;
      font-weight: 600;
      color: var(--primary);
      margin-bottom: 1rem;
      letter-spacing: 0;
    }
    .section-desc {
      color: var(--text-muted);
      max-width: 680px;
      margin: 0 auto 3rem;
      font-size: 1.05rem;
    }

    /* 卡片 */
    .card-custom {
      background: var(--card-bg);
      border: none;
      border-radius: var(--radius-card);
      box-shadow: var(--shadow-sm);
      padding: 2rem;
      transition: var(--transition);
      height: 100%;
    }
    .card-custom:hover {
      transform: translateY(-6px);
      box-shadow: var(--shadow-hover);
    }
    .card-icon {
      font-size: 2.2rem;
      color: var(--secondary);
      margin-bottom: 1.2rem;
    }
    .card-title {
      font-size: 1.35rem;
      font-weight: 600;
      margin-bottom: 0.8rem;
      color: var(--text-main);
    }
    .card-text {
      color: var(--text-muted);
      font-size: 0.98rem;
      margin-bottom: 1.2rem;
    }
    .link-arrow {
      color: var(--secondary);
      font-weight: 600;
      text-decoration: none;
      transition: var(--transition);
      display: inline-flex;
      align-items: center;
      gap: 4px;
    }
    .link-arrow:hover {
      color: var(--secondary-hover);
      transform: translateX(4px);
    }

    /* 优势数据 */
    .stats-bg {
      background-color: #F5F0EA;
      border-radius: var(--radius-card);
    }
    .stat-number {
      font-size: 2.3rem;
      font-weight: 700;
      color: var(--secondary);
      line-height: 1.2;
    }
    .stat-label {
      font-size: 0.9rem;
      color: var(--text-muted);
      font-weight: 500;
    }

    /* 案例卡片 */
    .case-card {
      background: var(--card-bg);
      border-radius: var(--radius-card);
      overflow: hidden;
      box-shadow: var(--shadow-sm);
      transition: var(--transition);
    }
    .case-card:hover {
      transform: translateY(-5px);
      box-shadow: var(--shadow-hover);
    }
    .case-img {
      width: 100%;
      height: 200px;
      object-fit: cover;
    }
    .case-body {
      padding: 1.5rem;
    }
    .case-tag {
      background: #F5F0EA;
      color: var(--primary);
      font-size: 0.75rem;
      font-weight: 600;
      padding: 0.2rem 0.8rem;
      border-radius: 20px;
      display: inline-block;
      margin-bottom: 0.5rem;
    }

    /* 解决方案图文 */
    .solution-img {
      border-radius: 12px;
      box-shadow: var(--shadow-sm);
      width: 100%;
      height: auto;
    }

    /* FAQ 手风琴 */
    .accordion-custom .accordion-item {
      border: none;
      border-bottom: 1px solid var(--border-light);
      background: transparent;
    }
    .accordion-custom .accordion-button {
      font-weight: 600;
      font-size: 1.1rem;
      color: var(--text-main);
      background: transparent;
      box-shadow: none;
      padding: 1.2rem 0;
    }
    .accordion-custom .accordion-button:not(.collapsed) {
      color: var(--primary);
      background: transparent;
    }
    .accordion-custom .accordion-button::after {
      filter: brightness(0.5);
    }
    .accordion-custom .accordion-body {
      color: var(--text-muted);
      padding: 0 0 1.5rem;
      line-height: 1.7;
    }

    /* 联系表单 */
    .form-control-custom {
      border: 1px solid var(--border-input);
      border-radius: var(--radius-input);
      padding: 0.7rem 1rem;
      background: white;
      transition: var(--transition);
    }
    .form-control-custom:focus {
      border-color: var(--primary);
      box-shadow: 0 0 0 0.2rem rgba(26,60,94,0.15);
    }

    /* 页脚 */
    .footer-custom {
      background-color: var(--footer-bg);
      color: var(--footer-text);
      padding: 3rem 0 1.5rem;
    }
    .footer-link {
      color: var(--footer-text);
      text-decoration: none;
      transition: var(--transition);
    }
    .footer-link:hover {
      color: white;
    }

    @media (max-width: 768px) {
      .hero-title {
        font-size: 2rem;
      }
      .hero-section {
        padding: 90px 0 60px;
      }
      .stat-number {
        font-size: 1.9rem;
      }
    }