/* roulang page: index */
:root {
      --primary: #1A1F36;
      --primary-light: #2D3561;
      --accent: #E94E1B;
      --accent-hover: #C43D12;
      --bg: #F8F9FC;
      --card-bg: #FFFFFF;
      --card-hover-bg: #F0F2F8;
      --text-primary: #1A1F36;
      --text-body: #4A4F66;
      --text-muted: #8B8FA6;
      --text-inverse: #FFFFFF;
      --border: #E8EBF2;
      --radius-card: 16px;
      --radius-element: 8px;
      --shadow-sm: 0 2px 8px rgba(26,31,54,0.06);
      --shadow-md: 0 8px 24px rgba(26,31,54,0.12);
      --font-sans: -apple-system, "PingFang SC", "Microsoft YaHei", "Noto Sans SC", sans-serif;
      --font-mono: 'Inter', var(--font-sans);
    }
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    body {
      font-family: var(--font-sans);
      background-color: var(--bg);
      color: var(--text-body);
      line-height: 1.75;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
    }
    img {
      max-width: 100%;
      height: auto;
      display: block;
    }
    a {
      text-decoration: none;
      color: inherit;
      transition: color 0.2s;
    }
    .container {
      max-width: 1280px;
      margin: 0 auto;
      padding: 0 32px;
    }
    @media (max-width: 768px) {
      .container {
        padding: 0 20px;
      }
    }

    /* 导航 */
    .site-header {
      position: sticky;
      top: 0;
      z-index: 50;
      background: rgba(255,255,255,0.92);
      backdrop-filter: blur(12px);
      box-shadow: 0 1px 0 var(--border);
      transition: box-shadow 0.3s;
    }
    .site-header.scrolled {
      box-shadow: 0 2px 12px rgba(0,0,0,0.05);
    }
    .header-inner {
      display: flex;
      align-items: center;
      justify-content: space-between;
      height: 72px;
    }
    .logo {
      font-weight: 700;
      font-size: 1.8rem;
      letter-spacing: -0.5px;
      color: var(--text-primary);
      display: flex;
      align-items: center;
      gap: 0px;
    }
    .logo span {
      color: var(--accent);
      
    }
    .nav-links {
      display: flex;
      align-items: center;
      gap: 32px;
    }
    .nav-links a {
      font-size: 1rem;
      font-weight: 500;
      color: var(--text-body);
      position: relative;
      padding: 4px 0;
    }
    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: -4px;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--accent);
      transition: width 0.25s ease;
    }
    .nav-links a:hover::after,
    .nav-links a.active::after {
      width: 100%;
    }
    .nav-cta {
      background: var(--accent);
      color: white !important;
      padding: 10px 24px !important;
      border-radius: 40px;
      font-weight: 600;
      transition: background 0.2s;
    }
    .nav-cta:hover {
      background: var(--accent-hover);
    }
    .menu-toggle {
      display: none;
      flex-direction: column;
      justify-content: center;
      gap: 6px;
      background: transparent;
      border: none;
      cursor: pointer;
    }
    .menu-toggle span {
      width: 28px;
      height: 2px;
      background: var(--text-primary);
      display: block;
      transition: 0.2s;
    }
    @media (max-width: 1023px) {
      .nav-links {
        display: none;
      }
      .menu-toggle {
        display: flex;
      }
      .mobile-menu {
        position: fixed;
        top: 72px;
        left: 0;
        width: 100%;
        background: white;
        flex-direction: column;
        padding: 32px;
        gap: 24px;
        box-shadow: var(--shadow-md);
        display: none;
      }
      .mobile-menu.open {
        display: flex;
      }
    }

    /* Hero */
    .hero {
      background: linear-gradient(135deg, #1A1F36 0%, #2D3561 100%);
      color: white;
      padding: 100px 0 100px;
      position: relative;
      overflow: hidden;
    }
    .hero::before {
      content: '';
      position: absolute;
      right: 0;
      top: 0;
      width: 50%;
      height: 100%;
      background: url('/assets/images/backpic/back-1.webp') center/cover no-repeat;
      opacity: 0.25;
      mask-image: radial-gradient(circle at center, black 20%, transparent 80%);
      -webkit-mask-image: radial-gradient(circle at center, black 20%, transparent 80%);
    }
    .hero-content {
      display: flex;
      align-items: center;
      gap: 60px;
      position: relative;
      z-index: 2;
    }
    .hero-text {
      flex: 1 1 50%;
    }
    .hero h1 {
      font-size: 3.2rem;
      font-weight: 700;
      line-height: 1.25;
      letter-spacing: -0.5px;
      margin-bottom: 24px;
      color: white;
    }
    .hero .subtitle {
      font-size: 1.2rem;
      color: rgba(255,255,255,0.75);
      margin-bottom: 32px;
      max-width: 500px;
    }
    .badge-group {
      display: flex;
      flex-wrap: wrap;
      gap: 12px;
      margin-bottom: 36px;
    }
    .badge {
      background: rgba(255,255,255,0.12);
      backdrop-filter: blur(6px);
      border-radius: 40px;
      padding: 6px 18px;
      font-size: 0.9rem;
      font-weight: 500;
      color: white;
      display: flex;
      align-items: center;
      gap: 6px;
    }
    .badge strong {
      font-family: var(--font-mono);
      color: #FFA07A;
      font-size: 1.1rem;
    }
    .cta-row {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }
    .btn {
      display: inline-block;
      font-weight: 600;
      border-radius: 40px;
      padding: 14px 32px;
      font-size: 1rem;
      transition: all 0.25s ease;
      border: none;
      cursor: pointer;
      text-align: center;
    }
    .btn-primary {
      background: var(--accent);
      color: white;
    }
    .btn-primary:hover { background: var(--accent-hover); }
    .btn-outline {
      background: transparent;
      border: 2px solid white;
      color: white;
    }
    .btn-outline:hover { background: white; color: var(--primary); }
    @media (max-width: 768px) {
      .hero-content { flex-direction: column; gap: 40px; }
      .hero h1 { font-size: 2.4rem; }
      .hero::before { width: 100%; opacity: 0.15; }
    }

    /* 通用板块 */
    .section {
      padding: 100px 0;
    }
    @media (max-width: 768px) {
      .section { padding: 70px 0; }
    }
    .section-title {
      font-size: 2rem;
      font-weight: 600;
      color: var(--text-primary);
      margin-bottom: 16px;
    }
    .section-sub {
      color: var(--text-muted);
      margin-bottom: 48px;
      font-size: 1.1rem;
    }

    /* 指标看板 */
    .metrics-grid {
      display: grid;
      grid-template-columns: repeat(4,1fr);
      background: var(--card-bg);
      border-radius: var(--radius-card);
      box-shadow: var(--shadow-sm);
      padding: 32px 16px;
      margin-top: -30px;
      position: relative;
      z-index: 5;
    }
    .metric-item {
      text-align: center;
      border-right: 1px solid var(--border);
      padding: 8px 0;
    }
    .metric-item:last-child { border-right: none; }
    .metric-number {
      font-family: var(--font-mono);
      font-size: 3rem;
      font-weight: 700;
      color: var(--accent);
      line-height: 1.2;
    }
    .metric-label {
      font-size: 0.9rem;
      color: var(--text-muted);
    }
    @media (max-width: 768px) {
      .metrics-grid { grid-template-columns: 1fr 1fr; border-right: none; }
      .metric-item { border-right: none; border-bottom: 1px solid var(--border); }
    }

    /* 服务卡片 */
    .services-grid {
      display: grid;
      grid-template-columns: repeat(3,1fr);
      gap: 28px;
    }
    .service-card {
      background: var(--card-bg);
      border-radius: var(--radius-card);
      padding: 32px;
      box-shadow: var(--shadow-sm);
      transition: all 0.25s;
      border: 1px solid var(--border);
      display: flex;
      flex-direction: column;
    }
    .service-card:hover {
      transform: translateY(-6px);
      box-shadow: var(--shadow-md);
      border-color: transparent;
      background: var(--card-hover-bg);
    }
    .card-icon {
      width: 56px;
      height: 56px;
      background: #F0F2F8;
      border-radius: 12px;
      display: flex;
      align-items: center;
      justify-content: center;
      margin-bottom: 24px;
      color: var(--primary);
    }
    .service-card h3 {
      font-size: 1.5rem;
      font-weight: 600;
      color: var(--text-primary);
      margin-bottom: 8px;
    }
    .tag-group {
      display: flex;
      flex-wrap: wrap;
      gap: 8px;
      margin-top: 16px;
    }
    .tag {
      background: #F0F2F8;
      color: var(--text-primary);
      font-size: 0.75rem;
      padding: 4px 12px;
      border-radius: 20px;
      font-weight: 500;
    }
    @media (max-width: 1023px) { .services-grid { grid-template-columns: repeat(2,1fr); } }
    @media (max-width: 640px) { .services-grid { grid-template-columns: 1fr; } }

    /* 对比 */
    .compare-row {
      display: flex;
      gap: 40px;
      align-items: center;
    }
    .compare-col {
      flex:1;
      background: white;
      border-radius: var(--radius-card);
      padding: 40px;
      border: 1px solid var(--border);
    }
    .compare-col.left { background: #F2F3F7; border-color: #ddd; }
    .compare-col.right { background: white; border-left: 6px solid var(--accent); }
    .compare-list { list-style: none; margin-top: 20px; }
    .compare-list li { margin-bottom: 14px; display: flex; align-items: center; gap: 10px; }
    .icon-fail { color: #bbb; }
    .icon-success { color: var(--accent); font-weight: bold; }
    @media (max-width: 768px) { .compare-row { flex-direction: column; } }

    /* FAQ */
    .faq-list {
      max-width: 800px;
      margin: 0 auto;
    }
    .faq-item {
      border-bottom: 1px solid var(--border);
      padding: 24px 0;
    }
    .faq-question {
      width: 100%;
      background: transparent;
      border: none;
      font-size: 1.2rem;
      font-weight: 600;
      color: var(--text-primary);
      display: flex;
      justify-content: space-between;
      align-items: center;
      cursor: pointer;
      text-align: left;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.4s ease;
      color: var(--text-body);
      padding-right: 20px;
    }
    .faq-item.open .faq-answer { max-height: 300px; padding-top: 16px; }
    .arrow { transition: transform 0.3s; }
    .faq-item.open .arrow { transform: rotate(180deg); color: var(--accent); }

    /* 表单 */
    .contact-form {
      background: #F0F2F8;
      border-radius: var(--radius-card);
      padding: 48px;
      max-width: 700px;
      margin: 0 auto;
    }
    .form-input {
      width: 100%;
      padding: 14px 16px;
      border: 1px solid var(--border);
      border-radius: var(--radius-element);
      margin-bottom: 20px;
      font-size: 1rem;
      background: white;
    }
    @media (max-width: 640px) {
      .contact-form { padding: 28px; }
    }

    /* 页脚 */
    .footer {
      background: var(--primary);
      color: #ccc;
      padding: 60px 0 30px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 32px;
      margin-bottom: 40px;
    }
    .footer a { color: #aaa; }
    @media (max-width: 768px) { .footer-grid { grid-template-columns: 1fr 1fr; } }