/* roulang page: index */
:root {
      --primary-deep: #2C3E50;
      --accent-orange: #E67E22;
      --bg-white: #FFFFFF;
      --bg-light-gray: #F4F7FA;
      --text-heading: #1A1A1A;
      --text-body: #4A4A4A;
      --text-muted: #7A7A7A;
      --border-light: rgba(44, 62, 80, 0.1);
      --shadow-sm: 0 2px 12px rgba(0,0,0,0.06);
      --shadow-md: 0 8px 24px rgba(0,0,0,0.10);
      --shadow-card-on-gray: 0 2px 16px rgba(0,0,0,0.08);
      --radius-card: 12px;
      --radius-btn: 8px;
      --font-inter: 'Inter', 'PingFang SC', 'Microsoft YaHei', system-ui, sans-serif;
      --transition-base: 0.25s ease;
    }
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    body {
      font-family: var(--font-inter);
      background-color: var(--bg-white);
      color: var(--text-body);
      line-height: 1.7;
      -webkit-font-smoothing: antialiased;
    }
    img {
      max-width: 100%;
      height: auto;
      display: block;
    }
    a {
      text-decoration: none;
      color: inherit;
      transition: var(--transition-base);
    }
    button, input, select {
      font-family: inherit;
      outline: none;
    }
    .container {
      max-width: 1200px;
      margin: 0 auto;
      padding: 0 24px;
    }
    /* 导航 */
    .main-header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      background: var(--bg-white);
      height: 72px;
      box-shadow: 0 1px 4px rgba(0,0,0,0.04);
      z-index: 100;
      display: flex;
      align-items: center;
    }
    .header-container {
      display: flex;
      align-items: center;
      justify-content: space-between;
      width: 100%;
    }
    .logo-area {
      display: flex;
      align-items: center;
      gap: 10px;
    }
    .logo-icon {
      width: 32px;
      height: 32px;
      background: var(--primary-deep);
      border-radius: 6px;
      display: flex;
      align-items: center;
      justify-content: center;
      color: white;
      font-weight: 700;
      font-size: 18px;
      position: relative;
    }
    .logo-icon::after {
      content: "";
      position: absolute;
      width: 8px;
      height: 8px;
      background: var(--accent-orange);
      border-radius: 50%;
      bottom: 3px;
      right: 3px;
    }
    .logo-text {
      font-weight: 700;
      font-size: 20px;
      color: var(--primary-deep);
      letter-spacing: 1px;
    }
    .nav-menu {
      display: flex;
      gap: 32px;
      align-items: center;
    }
    .nav-link {
      font-size: 15px;
      font-weight: 500;
      color: var(--text-body);
      padding: 8px 0;
      border-bottom: 2px solid transparent;
      transition: var(--transition-base);
    }
    .nav-link:hover {
      color: var(--primary-deep);
      border-bottom-color: var(--primary-deep);
    }
    .hamburger {
      display: none;
      flex-direction: column;
      gap: 5px;
      cursor: pointer;
      background: none;
      border: none;
    }
    .hamburger span {
      width: 25px;
      height: 2px;
      background: var(--primary-deep);
      transition: var(--transition-base);
    }
    @media (max-width: 1024px) {
      .nav-menu {
        display: none;
        position: fixed;
        top: 72px;
        left: 0;
        width: 100%;
        background: white;
        flex-direction: column;
        padding: 24px;
        box-shadow: 0 10px 20px rgba(0,0,0,0.05);
        gap: 16px;
      }
      .nav-menu.active {
        display: flex;
      }
      .hamburger {
        display: flex;
      }
    }
    /* Hero */
    .hero-section {
      margin-top: 72px;
      min-height: 520px;
      background: url('/assets/images/backpic/back-1.webp') center/cover no-repeat;
      position: relative;
      display: flex;
      align-items: center;
    }
    .hero-overlay {
      position: absolute;
      inset: 0;
      background: linear-gradient(135deg, rgba(44,62,80,0.85) 0%, rgba(44,62,80,0.4) 100%);
    }
    .hero-content {
      position: relative;
      display: flex;
      align-items: center;
      justify-content: space-between;
      gap: 40px;
      width: 100%;
    }
    .hero-text {
      flex: 1;
    }
    .hero-text h1 {
      font-size: clamp(36px, 5vw, 52px);
      font-weight: 700;
      color: white;
      line-height: 1.3;
      margin-bottom: 16px;
    }
    .hero-subtitle {
      font-size: 20px;
      color: rgba(255,255,255,0.8);
      margin-bottom: 32px;
    }
    .btn-primary {
      background: var(--accent-orange);
      color: white;
      padding: 14px 32px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      display: inline-block;
      border: none;
      cursor: pointer;
      transition: var(--transition-base);
    }
    .btn-primary:hover {
      background: #D35400;
    }
    .hero-image {
      flex: 0 0 45%;
      border-radius: 16px;
      overflow: hidden;
      box-shadow: 0 20px 35px rgba(0,0,0,0.3);
    }
    @media (max-width: 768px) {
      .hero-content {
        flex-direction: column;
        text-align: center;
        padding: 48px 0;
      }
      .hero-image {
        flex: 0 0 auto;
        width: 80%;
        margin-top: 24px;
      }
      .hero-section {
        min-height: 400px;
      }
    }
    /* 通用区块 */
    section {
      padding: 100px 0;
    }
    @media (max-width: 768px) {
      section {
        padding: 60px 0;
      }
    }
    .section-title {
      font-size: 36px;
      font-weight: 700;
      color: var(--text-heading);
      margin-bottom: 16px;
      line-height: 1.3;
    }
    .section-desc {
      font-size: 18px;
      color: var(--text-muted);
      margin-bottom: 48px;
    }
    /* 核心优势 非对称 */
    .features-grid {
      display: flex;
      gap: 24px;
    }
    .feature-large {
      flex: 0 0 50%;
      background: white;
      border-radius: var(--radius-card);
      padding: 32px;
      box-shadow: var(--shadow-sm);
      transition: var(--transition-base);
      border: 1px solid var(--border-light);
    }
    .feature-large:hover {
      box-shadow: var(--shadow-md);
      transform: translateY(-4px);
    }
    .features-small {
      flex: 0 0 50%;
      display: flex;
      flex-direction: column;
      gap: 24px;
    }
    .feature-item {
      background: white;
      border-radius: var(--radius-card);
      padding: 28px;
      box-shadow: var(--shadow-sm);
      transition: var(--transition-base);
      border: 1px solid var(--border-light);
    }
    .feature-item:hover {
      box-shadow: var(--shadow-md);
      transform: translateY(-3px);
    }
    .feature-icon {
      width: 48px;
      height: 48px;
      background: rgba(230,126,34,0.1);
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      color: var(--accent-orange);
      font-size: 24px;
      margin-bottom: 16px;
    }
    .feature-title {
      font-size: 24px;
      font-weight: 600;
      color: var(--text-heading);
      margin-bottom: 12px;
    }
    @media (max-width: 768px) {
      .features-grid {
        flex-direction: column;
      }
      .feature-large, .features-small {
        flex: auto;
      }
    }
    /* 数据看板 */
    .dashboard-bg {
      background: var(--bg-light-gray);
    }
    .stats-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 24px;
    }
    .stat-card {
      background: white;
      padding: 28px;
      border-radius: var(--radius-card);
      box-shadow: var(--shadow-card-on-gray);
      text-align: center;
      position: relative;
    }
    .stat-number {
      font-size: 42px;
      font-weight: 700;
      color: var(--primary-deep);
      margin-bottom: 8px;
    }
    .stat-label {
      font-size: 14px;
      color: var(--text-muted);
      text-transform: uppercase;
      letter-spacing: 0.5px;
    }
    .trend-up {
      color: #27ae60;
      font-weight: 600;
      margin-left: 5px;
    }
    @media (max-width: 768px) {
      .stats-grid {
        grid-template-columns: 1fr 1fr;
      }
    }
    /* 服务横向滚动 */
    .services-scroll {
      display: flex;
      gap: 24px;
      overflow-x: auto;
      padding-bottom: 16px;
      scroll-snap-type: x mandatory;
    }
    .service-card {
      min-width: 280px;
      background: white;
      border-radius: var(--radius-card);
      padding: 28px;
      box-shadow: var(--shadow-sm);
      scroll-snap-align: start;
      transition: var(--transition-base);
      border: 1px solid var(--border-light);
    }
    .service-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-md);
      border-bottom: 3px solid var(--accent-orange);
    }
    .service-icon {
      width: 48px;
      height: 48px;
      background: var(--accent-orange);
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      color: white;
      margin-bottom: 16px;
    }
    /* 结果对比 */
    .compare-row {
      display: flex;
      gap: 24px;
      align-items: center;
    }
    .compare-col {
      flex: 1;
      padding: 32px;
      border-radius: var(--radius-card);
    }
    .before-col {
      background: #F9FAFB;
      border: 1px solid #E5E7EB;
    }
    .after-col {
      background: white;
      border-left: 4px solid var(--primary-deep);
      box-shadow: var(--shadow-sm);
    }
    .vs-divider {
      font-weight: 700;
      font-size: 20px;
      color: var(--text-muted);
    }
    .metric-row {
      display: flex;
      justify-content: space-between;
      margin: 16px 0;
    }
    .customer-quote {
      font-style: italic;
      border-left: 4px solid var(--accent-orange);
      padding-left: 20px;
      margin-top: 24px;
    }
    @media (max-width: 768px) {
      .compare-row {
        flex-direction: column;
      }
      .vs-divider {
        transform: rotate(90deg);
      }
    }
    /* FAQ */
    .faq-list {
      max-width: 800px;
      margin: 0 auto;
    }
    .faq-item {
      border-bottom: 1px solid var(--border-light);
    }
    .faq-question {
      background: none;
      border: none;
      width: 100%;
      text-align: left;
      padding: 20px 0;
      font-size: 20px;
      font-weight: 600;
      color: var(--text-heading);
      display: flex;
      justify-content: space-between;
      cursor: pointer;
    }
    .faq-icon {
      transition: 0.2s;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease, padding 0.3s;
      color: var(--text-body);
    }
    .faq-item.active .faq-answer {
      max-height: 300px;
      padding-bottom: 20px;
    }
    .faq-item.active .faq-icon {
      color: var(--accent-orange);
      transform: rotate(45deg);
    }
    /* CTA */
    .cta-section {
      background: var(--primary-deep);
      color: white;
      padding: 80px 0;
    }
    .cta-grid {
      display: flex;
      gap: 40px;
      align-items: center;
    }
    .cta-form {
      flex: 1;
      background: rgba(255,255,255,0.1);
      backdrop-filter: blur(8px);
      padding: 32px;
      border-radius: var(--radius-card);
    }
    .form-input {
      width: 100%;
      padding: 14px;
      margin-bottom: 16px;
      border-radius: var(--radius-btn);
      border: none;
      background: white;
      box-shadow: inset 0 1px 3px rgba(0,0,0,0.08);
    }
    .form-input:focus {
      border: 2px solid var(--accent-orange);
    }
    .btn-submit {
      width: 100%;
      background: var(--accent-orange);
      color: white;
      border: none;
      padding: 14px;
      font-weight: 600;
      border-radius: var(--radius-btn);
      cursor: pointer;
    }
    .cta-image {
      flex: 0 0 35%;
    }
    @media (max-width: 768px) {
      .cta-grid {
        flex-direction: column;
      }
    }
    /* 页脚 */
    .footer {
      background: #1A252F;
      color: #B0BEC5;
      padding: 48px 0 24px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 32px;
    }
    .footer a:hover {
      color: white;
    }
    @media (max-width: 768px) {
      .footer-grid {
        grid-template-columns: 1fr 1fr;
      }
    }