/* roulang page: index */
:root {
      --primary: #1A5FDC;
      --primary-dark: #1349B0;
      --accent: #FF6B35;
      --bg: #FAFBFD;
      --card-bg: #FFFFFF;
      --text-main: #1E2A3A;
      --text-secondary: #5A6878;
      --text-muted: #8A9AA8;
      --border-light: #E9EDF4;
      --border-form: #D0D7E2;
      --shadow-card: 0 2px 16px rgba(0, 0, 0, 0.06);
      --shadow-hover: 0 6px 24px rgba(26, 95, 220, 0.12);
      --radius-card: 12px;
      --radius-btn: 8px;
      --radius-input: 6px;
      --font-title: "PingFang SC", "Microsoft YaHei", "Inter", sans-serif;
      --font-body: "PingFang SC", "Microsoft YaHei", "Inter", sans-serif;
      --transition: 0.25s ease;
      --nav-height: 68px;
    }

    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }

    body {
      font-family: var(--font-body);
      background-color: var(--bg);
      color: var(--text-main);
      line-height: 1.7;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
    }

    .container {
      max-width: 1200px;
      margin: 0 auto;
      padding: 0 24px;
    }

    /* 导航 */
    .nav {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: var(--nav-height);
      background: #FFFFFF;
      border-bottom: 1px solid var(--border-light);
      z-index: 100;
      display: flex;
      align-items: center;
      box-shadow: 0 1px 4px rgba(0,0,0,0.02);
    }

    .nav-container {
      display: flex;
      justify-content: space-between;
      align-items: center;
      width: 100%;
      max-width: 1200px;
      margin: 0 auto;
      padding: 0 24px;
    }

    .logo {
      font-family: var(--font-title);
      font-weight: 700;
      font-size: 1.5rem;
      color: var(--primary);
      letter-spacing: 0.5px;
      display: flex;
      align-items: baseline;
      gap: 8px;
      text-decoration: none;
    }
    .logo span {
      font-size: 0.8rem;
      font-weight: 500;
      color: var(--text-secondary);
      background: #F0F4FE;
      padding: 2px 8px;
      border-radius: 20px;
    }

    .nav-links {
      display: flex;
      gap: 2rem;
      list-style: none;
    }

    .nav-links a {
      text-decoration: none;
      color: var(--text-secondary);
      font-weight: 500;
      font-size: 0.95rem;
      padding-bottom: 6px;
      border-bottom: 3px solid transparent;
      transition: color var(--transition), border-color var(--transition);
    }

    .nav-links a:hover,
    .nav-links a.active {
      color: var(--primary);
      border-bottom-color: var(--primary);
    }

    .hamburger {
      display: none;
      background: none;
      border: none;
      font-size: 1.8rem;
      color: var(--text-main);
      cursor: pointer;
      line-height: 1;
    }

    @media (max-width: 768px) {
      .nav-links {
        display: none;
        position: absolute;
        top: var(--nav-height);
        left: 0;
        width: 100%;
        background: white;
        flex-direction: column;
        padding: 24px;
        box-shadow: 0 12px 24px rgba(0,0,0,0.08);
        gap: 1.2rem;
      }
      .nav-links.active {
        display: flex;
      }
      .hamburger {
        display: block;
      }
      .logo span {
        display: none;
      }
    }

    /* 板块通用 */
    section {
      padding: 100px 0;
    }
    @media (max-width: 768px) {
      section {
        padding: 60px 0;
      }
    }

    h2 {
      font-family: var(--font-title);
      font-size: 28px;
      font-weight: 600;
      margin-bottom: 16px;
      color: var(--text-main);
    }

    /* 首屏 Hero */
    .hero {
      margin-top: var(--nav-height);
      background: linear-gradient(180deg, #F2F6FD 0%, #FAFBFD 100%);
    }
    .hero-grid {
      display: grid;
      grid-template-columns: 6fr 4fr;
      gap: 48px;
      align-items: center;
    }
    .hero-left h1 {
      font-family: var(--font-title);
      font-size: 40px;
      font-weight: 700;
      line-height: 1.3;
      margin-bottom: 16px;
      color: #0B2447;
    }
    .hero-left .subtitle {
      font-size: 18px;
      color: var(--text-secondary);
      margin-bottom: 24px;
    }
    .hero-buttons {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }
    .btn {
      display: inline-block;
      padding: 12px 28px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      font-size: 1rem;
      text-decoration: none;
      transition: all var(--transition);
      cursor: pointer;
      border: 2px solid transparent;
    }
    .btn-primary {
      background: var(--primary);
      color: white;
      border-color: var(--primary);
    }
    .btn-primary:hover {
      background: var(--primary-dark);
      border-color: var(--primary-dark);
      box-shadow: 0 4px 12px rgba(26,95,220,0.3);
    }
    .btn-outline {
      background: transparent;
      color: var(--primary);
      border: 2px solid var(--primary);
    }
    .btn-outline:hover {
      background: var(--primary);
      color: white;
    }
    .hero-right {
      background: rgba(255,255,255,0.7);
      backdrop-filter: blur(2px);
      border-radius: var(--radius-card);
      padding: 28px;
      box-shadow: var(--shadow-card);
      border: 1px solid rgba(26,95,220,0.15);
    }
    .metric-item {
      display: flex;
      justify-content: space-between;
      align-items: center;
      margin-bottom: 20px;
    }
    .metric-label {
      font-size: 0.9rem;
      color: var(--text-secondary);
    }
    .metric-value {
      font-weight: 700;
      font-size: 1.5rem;
      color: var(--primary);
      display: flex;
      align-items: center;
      gap: 6px;
    }
    .pulse-dot {
      width: 10px;
      height: 10px;
      background: var(--accent);
      border-radius: 50%;
      display: inline-block;
      animation: pulse 1.8s infinite;
    }
    @keyframes pulse {
      0% { opacity: 1; transform: scale(1); }
      50% { opacity: 0.5; transform: scale(1.2); }
      100% { opacity: 1; transform: scale(1); }
    }

    @media (max-width: 768px) {
      .hero-grid {
        grid-template-columns: 1fr;
        gap: 30px;
      }
      .hero-left h1 {
        font-size: 28px;
      }
    }

    /* 卡片网格通用 */
    .grid-3 {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }
    .grid-2 {
      display: grid;
      grid-template-columns: repeat(2, 1fr);
      gap: 24px;
    }

    .card {
      background: var(--card-bg);
      border-radius: var(--radius-card);
      padding: 28px;
      box-shadow: var(--shadow-card);
      transition: all 0.3s ease;
      text-align: left;
    }
    .card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-hover);
    }

    /* 优势卡片左对齐+右侧描述+底部链接风格 */
    .advantage-card {
      display: flex;
      flex-direction: column;
    }
    .icon-circle {
      width: 48px;
      height: 48px;
      background: #EBF2FE;
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      margin-bottom: 20px;
      transition: transform 0.3s;
    }
    .card:hover .icon-circle {
      transform: scale(1.1);
    }
    .advantage-card h3 {
      font-size: 20px;
      font-weight: 600;
      margin-bottom: 10px;
    }
    .advantage-card p {
      color: var(--text-secondary);
      font-size: 0.95rem;
      margin-bottom: 16px;
    }
    .card-link {
      color: var(--primary);
      font-weight: 600;
      text-decoration: none;
      margin-top: auto;
    }

    /* 服务矩阵两行六格 */
    .service-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }
    .service-card {
      background: white;
      border-radius: var(--radius-card);
      padding: 24px;
      box-shadow: var(--shadow-card);
      transition: 0.3s;
    }
    .service-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-hover);
    }
    .service-icon {
      font-size: 2rem;
      color: var(--primary);
    }

    /* 对比区块 */
    .comparison-wrapper {
      display: grid;
      grid-template-columns: 1fr auto 1fr;
      align-items: center;
      gap: 20px;
    }
    .vs-badge {
      background: white;
      border-radius: 50%;
      width: 56px;
      height: 56px;
      display: flex;
      align-items: center;
      justify-content: center;
      font-weight: 700;
      color: var(--primary);
      box-shadow: 0 4px 12px rgba(0,0,0,0.1);
      border: 2px solid var(--border-light);
    }
    .compare-card {
      padding: 28px;
      border-radius: var(--radius-card);
      background: white;
      box-shadow: var(--shadow-card);
    }
    .compare-card.old {
      background: #F5F7FA;
    }
    .compare-card.new {
      background: #F0F6FF;
      border: 1px solid rgba(26,95,220,0.2);
    }
    .strikethrough {
      text-decoration: line-through;
      color: var(--text-muted);
    }
    @media (max-width: 768px) {
      .comparison-wrapper {
        grid-template-columns: 1fr;
      }
      .vs-badge {
        margin: 10px auto;
      }
      .grid-3, .service-grid, .grid-2 {
        grid-template-columns: 1fr;
      }
    }

    /* FAQ */
    .faq-item {
      border-bottom: 1px solid var(--border-light);
      padding: 18px 0;
    }
    .faq-question {
      display: flex;
      justify-content: space-between;
      align-items: center;
      font-weight: 600;
      cursor: pointer;
      color: var(--text-main);
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease;
      color: var(--text-secondary);
      padding-left: 16px;
      border-left: 3px solid var(--primary);
      margin-top: 8px;
    }
    .faq-item.active .faq-answer {
      max-height: 200px;
    }

    /* CTA */
    .cta-section {
      background: #E8F0FE;
      text-align: center;
      border-radius: 24px;
      margin: 0 24px;
    }
    .form-row {
      display: flex;
      gap: 12px;
      justify-content: center;
      flex-wrap: wrap;
      margin-top: 24px;
    }
    .form-input {
      padding: 12px 16px;
      border-radius: var(--radius-input);
      border: 1px solid var(--border-form);
      width: 240px;
      font-size: 1rem;
      outline: none;
    }
    .form-input:focus {
      border-color: var(--primary);
      box-shadow: 0 0 0 3px rgba(26,95,220,0.15);
    }

    /* 页脚 */
    .footer {
      background: #1E2A3A;
      color: #CBD5E1;
      padding: 48px 0 24px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 32px;
    }
    .footer a {
      color: #A0B4D0;
      text-decoration: none;
    }
    .footer a:hover {
      color: white;
    }
    @media (max-width: 768px) {
      .footer-grid {
        grid-template-columns: 1fr 1fr;
      }
    }