/* roulang page: index */
:root {
      --primary: #2563EB;
      --primary-hover: #1D4ED8;
      --accent: #0EA5E9;
      --bg: #F8FAFC;
      --card-bg: #FFFFFF;
      --text-main: #1E293B;
      --text-muted: #64748B;
      --border-light: #E2E8F0;
      --success: #10B981;
      --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.03);
      --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.05);
      --radius-lg: 1rem;
      --radius-xl: 1.5rem;
      --radius-full: 9999px;
      --font-stack: "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", system-ui, -apple-system, sans-serif;
    }

    * {
      box-sizing: border-box;
    }

    body {
      margin: 0;
      font-family: var(--font-stack);
      background-color: var(--bg);
      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;
    }

    button, .btn {
      cursor: pointer;
      font-family: inherit;
    }

    .container-custom {
      max-width: 1280px;
      margin-left: auto;
      margin-right: auto;
      padding-left: 1.5rem;
      padding-right: 1.5rem;
    }

    @media (min-width: 640px) {
      .container-custom {
        padding-left: 2rem;
        padding-right: 2rem;
      }
    }
    @media (min-width: 1024px) {
      .container-custom {
        padding-left: 3rem;
        padding-right: 3rem;
      }
    }

    /* 浮动导航 dock */
    .nav-dock {
      background: rgba(255, 255, 255, 0.8);
      backdrop-filter: blur(16px);
      -webkit-backdrop-filter: blur(16px);
      border-radius: var(--radius-full);
      border: 1px solid rgba(226, 232, 240, 0.7);
      box-shadow: 0 10px 25px -5px rgba(0, 0, 0, 0.05), 0 8px 10px -6px rgba(0, 0, 0, 0.02);
      transition: background 0.3s ease, box-shadow 0.3s ease;
    }
    .nav-scrolled {
      background: rgba(255, 255, 255, 0.95);
      box-shadow: 0 10px 30px -10px rgba(0,0,0,0.08);
    }
    .nav-link {
      font-size: 0.9rem;
      font-weight: 500;
      color: #475569;
      transition: color 0.2s;
      padding: 0.4rem 0.8rem;
    }
    .nav-link:hover {
      color: var(--primary);
    }

    /* 按钮样式 */
    .btn-primary {
      background-color: var(--primary);
      color: white;
      border-radius: var(--radius-xl);
      padding: 0.75rem 2rem;
      font-weight: 600;
      display: inline-flex;
      align-items: center;
      justify-content: center;
      transition: background 0.2s, box-shadow 0.2s, transform 0.1s;
      border: none;
      box-shadow: 0 2px 6px rgba(37,99,235,0.2);
    }
    .btn-primary:hover {
      background-color: var(--primary-hover);
      box-shadow: 0 6px 14px rgba(37,99,235,0.3);
      transform: translateY(-1px);
    }
    .btn-outline {
      background: transparent;
      border: 2px solid var(--primary);
      color: var(--primary);
      border-radius: var(--radius-xl);
      padding: 0.65rem 1.8rem;
      font-weight: 600;
      transition: background 0.2s, color 0.2s;
      display: inline-flex;
      align-items: center;
      justify-content: center;
    }
    .btn-outline:hover {
      background-color: #eff6ff;
    }

    /* 卡片悬停 */
    .card-hover {
      transition: all 0.3s ease;
      border: 1px solid #f1f5f9;
      border-radius: var(--radius-xl);
      background: white;
      box-shadow: var(--shadow-sm);
    }
    .card-hover:hover {
      box-shadow: var(--shadow-md);
      transform: translateY(-4px);
      border-color: #e2e8f0;
    }

    /* 虚线分隔优势卡 */
    .advantage-divider {
      border-right: 1px dashed #cbd5e1;
    }
    @media (max-width: 767px) {
      .advantage-divider {
        border-right: none;
        border-bottom: 1px dashed #cbd5e1;
        padding-bottom: 2rem;
        margin-bottom: 2rem;
      }
    }

    /* 功能标签切换 */
    .tab-active {
      border-left: 4px solid var(--primary);
      color: var(--primary);
      font-weight: 600;
      background-color: #f0f7ff;
      border-radius: 0 0.75rem 0.75rem 0;
    }

    /* FAQ 手风琴 */
    .faq-item {
      border-bottom: 1px solid var(--border-light);
    }
    .faq-answer {
      background-color: #f8fafc;
      border-radius: 0.75rem;
      margin-top: 0.5rem;
      margin-bottom: 0.5rem;
      padding: 1rem 1.5rem;
      color: #334155;
      line-height: 1.7;
    }

    /* 背景纹理 */
    .hero-bg {
      background: radial-gradient(circle at 20% 30%, #eff6ff 0%, #f8fafc 70%);
      position: relative;
    }
    .hero-bg::before {
      content: "";
      position: absolute;
      inset: 0;
      background-image: radial-gradient(#cbd5e1 0.8px, transparent 0.8px);
      background-size: 26px 26px;
      opacity: 0.25;
      pointer-events: none;
    }

    .cta-bg {
      background: radial-gradient(circle at 60% 40%, #dbeafe 0%, #f0f9ff 80%);
      position: relative;
    }
    .cta-bg::after {
      content: "";
      position: absolute;
      top: -20px;
      right: 0;
      width: 300px;
      height: 300px;
      background: radial-gradient(circle, rgba(14,165,233,0.08) 0%, transparent 70%);
      border-radius: 50%;
    }

    /* 平滑滚动 */
    html {
      scroll-behavior: smooth;
    }

    @media (max-width: 768px) {
      .nav-dock {
        border-radius: 1.5rem;
      }
      .mobile-menu {
        display: flex;
      }
    }

.scrollbar-hide::-webkit-scrollbar { display: none; }
    .scrollbar-hide { -ms-overflow-style: none; scrollbar-width: none; }
    .faq-answer { transition: all 0.2s; }
    .tab-trigger { transition: background 0.2s, color 0.2s; }