/* roulang page: index */
:root {
      --primary: #E8452D;
      --primary-dark: #C13A25;
      --secondary: #1B2A4A;
      --secondary-light: #25395C;
      --accent: #F5A623;
      --accent-light: #F7B84D;
      --bg-light: #F8F9FA;
      --bg-white: #FFFFFF;
      --text-dark: #1E293B;
      --text-muted: #64748B;
      --text-light: #F1F5F9;
      --border-color: #E2E8F0;
      --radius-sm: 8px;
      --radius-md: 12px;
      --radius-lg: 16px;
      --shadow-sm: 0 2px 8px rgba(0,0,0,0.06);
      --shadow-md: 0 8px 24px rgba(0,0,0,0.12);
      --shadow-lg: 0 16px 32px rgba(0,0,0,0.15);
      --transition-base: 0.2s ease;
      --font-sans: "Noto Sans SC", "PingFang SC", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
      --max-width: 1200px;
      --section-padding: 80px;
    }
    
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    
    html {
      scroll-behavior: smooth;
      scroll-padding-top: 80px;
    }
    
    body {
      font-family: var(--font-sans);
      line-height: 1.6;
      color: var(--text-dark);
      background-color: var(--bg-light);
      -webkit-font-smoothing: antialiased;
      -moz-osx-font-smoothing: grayscale;
    }
    
    img {
      max-width: 100%;
      height: auto;
      display: block;
    }
    
    a {
      text-decoration: none;
      color: inherit;
      transition: var(--transition-base);
    }
    
    button, input, textarea {
      font-family: inherit;
    }
    
    .container {
      max-width: var(--max-width);
      margin: 0 auto;
      padding: 0 20px;
      width: 100%;
    }
    
    /* 导航系统 */
    .site-header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 1000;
      background: rgba(255,255,255,0.97);
      backdrop-filter: blur(10px);
      border-bottom: 1px solid transparent;
      transition: background var(--transition-base), box-shadow var(--transition-base), border-color var(--transition-base);
      padding: 12px 0;
    }
    
    .site-header.scrolled {
      background: rgba(255,255,255,0.98);
      box-shadow: 0 4px 20px rgba(0,0,0,0.08);
      border-bottom: 1px solid var(--border-color);
    }
    
    .header-inner {
      display: flex;
      align-items: center;
      justify-content: space-between;
      flex-wrap: wrap;
    }
    
    .logo {
      font-size: 24px;
      font-weight: 700;
      color: var(--secondary);
      display: flex;
      align-items: center;
      gap: 6px;
    }
    
    .logo-icon {
      color: var(--primary);
      font-size: 28px;
      line-height: 1;
    }
    
    .logo-text {
      letter-spacing: 1px;
    }
    
    .nav-menu {
      display: flex;
      align-items: center;
      gap: 32px;
    }
    
    .nav-link {
      font-weight: 500;
      font-size: 15px;
      color: var(--secondary);
      position: relative;
      padding: 4px 0;
      transition: color var(--transition-base);
    }
    
    .nav-link::after {
      content: '';
      position: absolute;
      bottom: 0;
      left: 0;
      width: 0%;
      height: 2px;
      background: var(--primary);
      transition: width var(--transition-base);
    }
    
    .nav-link:hover,
    .nav-link.active {
      color: var(--primary);
    }
    
    .nav-link:hover::after,
    .nav-link.active::after {
      width: 100%;
    }
    
    .nav-cta {
      background: var(--primary);
      color: white;
      padding: 10px 24px;
      border-radius: var(--radius-sm);
      font-weight: 600;
      font-size: 14px;
      margin-left: 12px;
      border: none;
      cursor: pointer;
      transition: all var(--transition-base);
      display: inline-block;
    }
    
    .nav-cta:hover {
      background: var(--primary-dark);
      transform: translateY(-2px);
      box-shadow: 0 4px 12px rgba(232,69,45,0.3);
      color: white;
    }
    
    .hamburger {
      display: none;
      background: none;
      border: none;
      font-size: 24px;
      color: var(--secondary);
      cursor: pointer;
      padding: 5px;
    }
    
    /* 移动端菜单 */
    @media (max-width: 992px) {
      .hamburger {
        display: block;
      }
      .nav-menu {
        position: fixed;
        top: 70px;
        left: 0;
        width: 100%;
        background: rgba(255,255,255,0.98);
        backdrop-filter: blur(15px);
        flex-direction: column;
        align-items: flex-start;
        gap: 16px;
        padding: 24px 32px;
        box-shadow: var(--shadow-md);
        transform: translateY(-10px);
        opacity: 0;
        visibility: hidden;
        transition: all 0.3s ease;
        border-bottom: 1px solid var(--border-color);
      }
      .nav-menu.open {
        transform: translateY(0);
        opacity: 1;
        visibility: visible;
      }
      .nav-cta {
        margin-left: 0;
        width: 100%;
        text-align: center;
      }
    }
    
    /* 区块通用 */
    section {
      padding: var(--section-padding) 0;
      position: relative;
    }
    
    @media (max-width: 768px) {
      :root {
        --section-padding: 48px;
      }
    }
    
    .section-title {
      font-size: 28px;
      font-weight: 700;
      line-height: 1.3;
      margin-bottom: 12px;
      color: var(--secondary);
    }
    
    .section-subtitle {
      font-size: 16px;
      color: var(--text-muted);
      margin-bottom: 40px;
      max-width: 700px;
    }
    
    .text-center {
      text-align: center;
    }
    
    .mx-auto {
      margin-left: auto;
      margin-right: auto;
    }
    
    /* Hero */
    #home {
      padding-top: 140px;
      padding-bottom: 60px;
      background: linear-gradient(135deg, #0F172A 0%, #1B2A4A 100%);
      color: white;
      position: relative;
      overflow: hidden;
    }
    
    .hero-grid {
      display: flex;
      align-items: center;
      gap: 48px;
    }
    
    .hero-content {
      flex: 1 1 55%;
    }
    
    .hero-visual {
      flex: 1 1 45%;
      border-radius: var(--radius-lg);
      overflow: hidden;
      box-shadow: 0 20px 40px rgba(0,0,0,0.4);
    }
    
    .hero-visual img {
      width: 100%;
      height: auto;
      object-fit: cover;
    }
    
    .hero-badge {
      display: inline-block;
      background: rgba(245,166,35,0.15);
      color: var(--accent);
      padding: 6px 16px;
      border-radius: 30px;
      font-size: 14px;
      font-weight: 600;
      margin-bottom: 20px;
      letter-spacing: 0.5px;
    }
    
    h1 {
      font-size: 40px;
      font-weight: 700;
      line-height: 1.2;
      margin-bottom: 20px;
      color: white;
    }
    
    .hero-subtitle {
      font-size: 18px;
      color: rgba(255,255,255,0.85);
      margin-bottom: 32px;
      max-width: 550px;
    }
    
    .hero-actions {
      display: flex;
      align-items: center;
      gap: 16px;
      flex-wrap: wrap;
    }
    
    .btn-primary {
      background: var(--primary);
      color: white;
      padding: 14px 32px;
      border-radius: var(--radius-sm);
      font-weight: 600;
      font-size: 16px;
      border: none;
      cursor: pointer;
      transition: all var(--transition-base);
      display: inline-block;
      box-shadow: 0 4px 10px rgba(232,69,45,0.3);
    }
    
    .btn-primary:hover {
      background: var(--primary-dark);
      transform: translateY(-2px);
      box-shadow: 0 8px 20px rgba(232,69,45,0.4);
    }
    
    .btn-outline-light {
      background: transparent;
      color: white;
      border: 2px solid rgba(255,255,255,0.5);
      padding: 12px 28px;
      border-radius: var(--radius-sm);
      font-weight: 600;
      transition: all var(--transition-base);
    }
    
    .btn-outline-light:hover {
      background: rgba(255,255,255,0.1);
      border-color: white;
    }
    
    .kpi-row {
      display: flex;
      gap: 32px;
      margin-top: 48px;
      flex-wrap: wrap;
    }
    
    .kpi-item {
      flex: 1;
      min-width: 140px;
    }
    
    .kpi-number {
      font-size: 32px;
      font-weight: 700;
      color: var(--accent);
      line-height: 1.2;
    }
    
    .kpi-label {
      font-size: 14px;
      color: rgba(255,255,255,0.7);
      margin-top: 4px;
    }
    
    @media (max-width: 992px) {
      .hero-grid {
        flex-direction: column;
      }
      h1 {
        font-size: 32px;
      }
    }
    
    /* 核心优势 */
    #features {
      background: var(--bg-white);
    }
    
    .features-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
      margin-bottom: 40px;
    }
    
    .feature-card {
      background: var(--bg-light);
      border-radius: var(--radius-md);
      padding: 28px 24px;
      transition: all var(--transition-base);
      border: 1px solid transparent;
      display: flex;
      flex-direction: column;
    }
    
    .feature-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-md);
      border-color: var(--border-color);
    }
    
    .feature-card.accent-card {
      background: var(--primary);
      color: white;
      border: none;
    }
    
    .feature-icon {
      font-size: 32px;
      color: var(--primary);
      margin-bottom: 16px;
    }
    
    .accent-card .feature-icon {
      color: white;
    }
    
    .feature-title {
      font-size: 20px;
      font-weight: 600;
      margin-bottom: 10px;
    }
    
    .feature-desc {
      font-size: 15px;
      color: var(--text-muted);
      line-height: 1.6;
    }
    
    .accent-card .feature-desc {
      color: rgba(255,255,255,0.85);
    }
    
    @media (max-width: 768px) {
      .features-grid {
        grid-template-columns: 1fr;
      }
    }
    
    /* 服务矩阵 */
    #services {
      background: var(--bg-light);
    }
    
    .tabs-nav {
      display: flex;
      gap: 8px;
      margin-bottom: 32px;
      flex-wrap: wrap;
      border-bottom: 1px solid var(--border-color);
    }
    
    .tab-btn {
      background: none;
      border: none;
      padding: 12px 24px;
      font-weight: 600;
      cursor: pointer;
      color: var(--text-muted);
      border-bottom: 3px solid transparent;
      transition: all var(--transition-base);
    }
    
    .tab-btn.active {
      color: var(--primary);
      border-bottom-color: var(--primary);
    }
    
    .services-grid {
      display: grid;
      grid-template-columns: repeat(2, 1fr);
      gap: 24px;
    }
    
    .service-item {
      background: white;
      border-radius: var(--radius-md);
      overflow: hidden;
      box-shadow: var(--shadow-sm);
      transition: var(--transition-base);
      display: flex;
      flex-direction: column;
    }
    
    .service-item:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-md);
    }
    
    .service-img {
      height: 200px;
      background-size: cover;
      background-position: center;
    }
    
    .service-content {
      padding: 20px;
      display: flex;
      justify-content: space-between;
      align-items: center;
    }
    
    .service-name {
      font-weight: 700;
      font-size: 18px;
    }
    
    .service-tag {
      background: #FEF3C7;
      color: #B45309;
      padding: 4px 12px;
      border-radius: 20px;
      font-size: 13px;
      font-weight: 600;
    }
    
    @media (max-width: 768px) {
      .services-grid {
        grid-template-columns: 1fr;
      }
    }
    
    /* 数据对比 */
    #data {
      background: white;
    }
    
    .compare-wrapper {
      display: flex;
      gap: 24px;
      align-items: stretch;
    }
    
    .compare-card {
      flex: 1;
      background: #F1F5F9;
      border-radius: var(--radius-lg);
      padding: 32px 28px;
    }
    
    .compare-card.after {
      background: #FFF7ED;
      border: 1px solid var(--primary);
    }
    
    .compare-label {
      font-weight: 700;
      margin-bottom: 16px;
      font-size: 18px;
      color: var(--secondary);
      display: flex;
      align-items: center;
      gap: 8px;
    }
    
    .metric {
      font-size: 38px;
      font-weight: 700;
      color: var(--text-dark);
    }
    
    .after .metric {
      color: var(--primary);
    }
    
    .delta {
      color: var(--primary);
      font-weight: 600;
      margin-top: 8px;
    }
    
    @media (max-width: 768px) {
      .compare-wrapper {
        flex-direction: column;
      }
    }
    
    /* FAQ */
    #faq {
      background: var(--bg-light);
    }
    
    .faq-list {
      max-width: 800px;
      margin: 0 auto;
    }
    
    .faq-item {
      border-bottom: 1px solid var(--border-color);
      background: white;
      margin-bottom: 12px;
      border-radius: var(--radius-sm);
    }
    
    .faq-question {
      padding: 20px 24px;
      font-weight: 600;
      display: flex;
      justify-content: space-between;
      align-items: center;
      cursor: pointer;
      background: none;
      border: none;
      width: 100%;
      text-align: left;
    }
    
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease;
      padding: 0 24px;
      background: #F8FAFC;
    }
    
    .faq-item.active .faq-answer {
      max-height: 200px;
      padding: 16px 24px;
    }
    
    /* CTA 表单 */
    #contact {
      background: linear-gradient(135deg, #1B2A4A, #0F172A);
      color: white;
    }
    
    .cta-grid {
      display: flex;
      gap: 48px;
      align-items: center;
    }
    
    .cta-text {
      flex: 1;
    }
    
    .cta-form {
      flex: 1;
      background: rgba(255,255,255,0.1);
      backdrop-filter: blur(10px);
      padding: 32px;
      border-radius: var(--radius-lg);
    }
    
    .form-input {
      width: 100%;
      padding: 14px 18px;
      margin-bottom: 16px;
      background: white;
      border: none;
      border-radius: var(--radius-sm);
      font-size: 15px;
      outline: none;
      border: 2px solid transparent;
      transition: border-color var(--transition-base);
    }
    
    .form-input:focus {
      border-color: var(--accent);
    }
    
    .btn-submit {
      background: var(--accent);
      color: #1E293B;
      font-weight: 700;
      padding: 14px 24px;
      border: none;
      border-radius: var(--radius-sm);
      cursor: pointer;
      width: 100%;
      transition: all var(--transition-base);
    }
    
    .btn-submit:hover {
      background: var(--accent-light);
      transform: scale(1.02);
    }
    
    .trust-badge {
      display: flex;
      align-items: center;
      gap: 12px;
      margin-top: 16px;
      color: rgba(255,255,255,0.8);
    }
    
    @media (max-width: 768px) {
      .cta-grid {
        flex-direction: column;
      }
    }
    
    /* 页脚 */
    footer {
      background: var(--secondary);
      color: #CBD5E1;
      padding: 48px 0 20px;
    }
    
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 32px;
    }
    
    .footer-logo {
      font-size: 24px;
      font-weight: 700;
      color: white;
      margin-bottom: 12px;
    }
    
    .footer-link {
      color: #CBD5E1;
      display: block;
      margin-bottom: 8px;
    }
    
    .footer-link:hover {
      color: var(--primary);
    }
    
    .copyright {
      margin-top: 32px;
      text-align: center;
      border-top: 1px solid rgba(255,255,255,0.1);
      padding-top: 20px;
      font-size: 14px;
    }
    
    @media (max-width: 768px) {
      .footer-grid {
        grid-template-columns: 1fr;
      }
    }