/* roulang page: index */
:root {
      --primary: #0A4D3C;
      --primary-hover: #073D2E;
      --accent: #F3752B;
      --accent-hover: #e1651f;
      --bg: #FDFBF7;
      --text: #1A1A1A;
      --text-secondary: #5C5C5C;
      --border: #E5E5E5;
      --card-bg: #FFFFFF;
      --card-shadow: 0 4px 20px rgba(0,0,0,0.04);
      --card-hover-shadow: 0 12px 32px rgba(0,0,0,0.08);
      --radius-sm: 8px;
      --radius-md: 12px;
      --radius-lg: 16px;
      --font-heading: 'Inter', 'SF Pro Display', -apple-system, sans-serif;
      --font-body: 'Inter', 'SF Pro Text', -apple-system, sans-serif;
    }
    * {
      box-sizing: border-box;
    }
    body {
      margin: 0;
      font-family: var(--font-body);
      background-color: var(--bg);
      color: var(--text);
      line-height: 1.7;
      -webkit-font-smoothing: antialiased;
    }
    h1, h2, h3, h4 {
      font-family: var(--font-heading);
      font-weight: 700;
      letter-spacing: -0.02em;
      margin: 0;
    }
    .container {
      max-width: 1280px;
      margin-left: auto;
      margin-right: auto;
      padding-left: 1.5rem;
      padding-right: 1.5rem;
    }
    /* 导航 */
    .nav-link {
      color: var(--text-secondary);
      text-decoration: none;
      font-weight: 500;
      transition: color 0.2s;
      font-size: 0.95rem;
    }
    .nav-link:hover {
      color: var(--primary);
    }
    .logo-text {
      font-family: var(--font-heading);
      font-weight: 800;
      font-size: 1.5rem;
      color: var(--primary);
      letter-spacing: -0.03em;
      text-decoration: none;
    }
    /* 卡片 */
    .feature-card {
      background: var(--card-bg);
      border-radius: var(--radius-md);
      padding: 2rem;
      box-shadow: var(--card-shadow);
      transition: all 0.25s ease;
    }
    .feature-card:hover {
      box-shadow: var(--card-hover-shadow);
      transform: translateY(-4px);
    }
    /* 按钮 */
    .btn-primary {
      background-color: var(--accent);
      color: white;
      font-weight: 600;
      padding: 14px 32px;
      border-radius: var(--radius-sm);
      display: inline-block;
      text-decoration: none;
      transition: background-color 0.2s, box-shadow 0.2s;
      border: none;
      cursor: pointer;
      font-size: 1rem;
      text-align: center;
    }
    .btn-primary:hover {
      background-color: var(--accent-hover);
      box-shadow: 0 4px 14px rgba(243,117,43,0.4);
    }
    .btn-outline {
      background: transparent;
      border: 2px solid var(--primary);
      color: var(--primary);
      font-weight: 600;
      padding: 12px 32px;
      border-radius: var(--radius-sm);
      display: inline-block;
      text-decoration: none;
      transition: all 0.25s;
      font-size: 1rem;
      text-align: center;
    }
    .btn-outline:hover {
      background: var(--primary);
      color: white;
    }
    /* 流程步骤连接线 */
    .step-item {
      position: relative;
      flex: 1;
      text-align: center;
    }
    .step-circle {
      width: 48px;
      height: 48px;
      background: var(--accent);
      color: white;
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      font-weight: 800;
      font-size: 1.3rem;
      margin: 0 auto 1rem;
      position: relative;
      z-index: 2;
    }
    .step-line {
      position: absolute;
      top: 24px;
      left: 60%;
      width: 80%;
      height: 2px;
      border-top: 2px dashed var(--primary);
      z-index: 1;
      opacity: 0.5;
    }
    .step-item:last-child .step-line {
      display: none;
    }
    /* FAQ 手风琴 */
    .faq-item {
      border-bottom: 1px solid var(--border);
      padding: 20px 0;
    }
    .faq-question {
      font-weight: 600;
      font-size: 1.1rem;
      cursor: pointer;
      display: flex;
      justify-content: space-between;
      align-items: center;
      color: var(--text);
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.35s ease, padding 0.35s ease;
      color: var(--text-secondary);
    }
    .faq-item.active .faq-answer {
      max-height: 200px;
      padding-top: 12px;
    }
    .faq-icon {
      font-size: 1.4rem;
      color: var(--primary);
      transition: transform 0.2s;
    }
    /* 移动端菜单 */
    .mobile-menu {
      display: none;
    }
    @media (max-width: 768px) {
      .desktop-nav {
        display: none;
      }
      .mobile-menu {
        display: block;
      }
      .container {
        padding-left: 1.2rem;
        padding-right: 1.2rem;
      }
      h1 {
        font-size: 2.2rem !important;
        line-height: 1.2 !important;
      }
      h2 {
        font-size: 1.8rem !important;
      }
      .step-line {
        display: none;
      }
    }