/* roulang page: index */
/* 设计变量与全局重置 */
    :root {
      --primary: #0A4B6E;
      --primary-light: #1D6B92;
      --primary-dark: #073A55;
      --accent: #C49A2B;
      --accent-light: #D9B54A;
      --bg-page: #F8FAFC;
      --bg-card: #FFFFFF;
      --bg-stripe: #EBF2F7;
      --text-main: #1E293B;
      --text-secondary: #475569;
      --text-muted: #94A3B8;
      --success: #10B981;
      --danger: #EF4444;
      --border-light: #E2E8F0;
      --shadow-sm: 0 4px 12px rgba(10, 75, 110, 0.06);
      --shadow-md: 0 8px 24px rgba(10, 75, 110, 0.12);
      --radius-xl: 16px;
      --radius-lg: 12px;
      --radius-md: 8px;
      --transition: 200ms ease;
    }
    * {
      box-sizing: border-box;
    }
    body {
      margin: 0;
      font-family: 'Inter', 'Noto Sans SC', 'PingFang SC', 'Microsoft YaHei', sans-serif;
      background-color: var(--bg-page);
      color: var(--text-main);
      line-height: 1.6;
      -webkit-font-smoothing: antialiased;
    }
    img {
      max-width: 100%;
      height: auto;
      display: block;
    }
    a {
      text-decoration: none;
      color: inherit;
      transition: color var(--transition);
    }
    button, input, textarea {
      font-family: inherit;
    }
    .container {
      max-width: 1280px;
      margin-left: auto;
      margin-right: auto;
      padding-left: 1.5rem;
      padding-right: 1.5rem;
    }
    /* 导航样式 */
    .nav-blur {
      background: rgba(255,255,255,0.92);
      backdrop-filter: blur(12px);
      border-bottom: 1px solid var(--border-light);
    }
    .nav-link {
      position: relative;
      font-size: 0.9375rem;
      font-weight: 500;
      color: var(--text-secondary);
      padding: 0.5rem 0.25rem;
      transition: color var(--transition);
    }
    .nav-link::after {
      content: '';
      position: absolute;
      bottom: -2px;
      left: 50%;
      transform: translateX(-50%);
      width: 0;
      height: 2px;
      background: var(--primary);
      transition: width var(--transition);
    }
    .nav-link:hover, .nav-link:focus-visible {
      color: var(--primary);
    }
    .nav-link:hover::after, .nav-link:focus-visible::after {
      width: 100%;
    }
    /* 按钮系统 */
    .btn-primary {
      background-color: var(--primary);
      color: white;
      border-radius: var(--radius-lg);
      padding: 0.75rem 2rem;
      font-weight: 600;
      border: none;
      cursor: pointer;
      transition: background var(--transition), box-shadow var(--transition), transform var(--transition);
      box-shadow: 0 4px 10px rgba(10,75,110,0.15);
      display: inline-flex;
      align-items: center;
      justify-content: center;
      gap: 0.5rem;
    }
    .btn-primary:hover {
      background-color: var(--primary-light);
      box-shadow: 0 8px 18px rgba(10,75,110,0.25);
      transform: translateY(-1px);
    }
    .btn-outline {
      background: transparent;
      color: var(--primary);
      border: 1.5px solid var(--primary);
      border-radius: var(--radius-lg);
      padding: 0.75rem 2rem;
      font-weight: 600;
      cursor: pointer;
      transition: background var(--transition), color var(--transition), box-shadow var(--transition);
    }
    .btn-outline:hover {
      background: rgba(10,75,110,0.04);
      box-shadow: 0 4px 10px rgba(10,75,110,0.08);
    }
    .btn-white {
      background: transparent;
      color: white;
      border: 1.5px solid white;
      border-radius: var(--radius-lg);
      padding: 0.75rem 2rem;
      font-weight: 600;
      cursor: pointer;
      transition: all var(--transition);
    }
    .btn-white:hover {
      background: white;
      color: var(--primary);
      box-shadow: 0 8px 18px rgba(0,0,0,0.1);
    }
    /* 卡片系统 */
    .card {
      background: var(--bg-card);
      border-radius: var(--radius-xl);
      box-shadow: var(--shadow-sm);
      transition: transform var(--transition), box-shadow var(--transition);
      padding: 2rem;
      height: 100%;
    }
    .card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-md);
    }
    .pain-card {
      background: #F1F5F9;
      border-left: 5px solid var(--accent);
      padding: 1.75rem;
      border-radius: var(--radius-lg);
    }
    /* 装饰元素 */
    .section-title {
      font-size: 2.25rem;
      font-weight: 700;
      line-height: 1.3;
      margin-bottom: 0.75rem;
      position: relative;
      display: inline-block;
    }
    .section-title::after {
      content: '';
      display: block;
      width: 60px;
      height: 4px;
      background: var(--primary);
      margin-top: 0.5rem;
      border-radius: 2px;
    }
    @media (max-width: 768px) {
      .section-title {
        font-size: 1.75rem;
      }
    }
    /* 手风琴动画 */
    .faq-content {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease;
    }
    .faq-item.open .faq-content {
      max-height: 200px;
    }
    /* 英雄区域波形背景 */
    .hero-wave {
      background: linear-gradient(135deg, #F8FAFC 0%, #EBF2F7 100%);
      position: relative;
      overflow: hidden;
    }
    .hero-wave::before {
      content: '';
      position: absolute;
      right: 0;
      top: 0;
      width: 50%;
      height: 100%;
      background-image: url('/assets/images/backpic/back-1.webp');
      background-size: cover;
      background-position: center;
      opacity: 0.25;
      z-index: 0;
    }
    @media (max-width: 768px) {
      .hero-wave::before {
        width: 100%;
        opacity: 0.15;
      }
    }
    /* 自定义网格偏移 */
    .grid-advantage {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 2rem;
    }
    @media (max-width: 1024px) {
      .grid-advantage {
        grid-template-columns: repeat(2, 1fr);
      }
    }
    @media (max-width: 640px) {
      .grid-advantage {
        grid-template-columns: 1fr;
        gap: 1.5rem;
      }
    }