/* roulang page: index */
/* ----- 设计变量与基础重置 ----- */
    :root {
      --primary: #E83E2D;
      --primary-hover: #C53020;
      --primary-light: #FDE8E7;
      --accent: #00C2A8;
      --accent-hover: #00A28B;
      --dark-bg: #1A1D23;
      --warm-gray: #F2F0EB;
      --text-main: #1A1D23;
      --text-secondary: #5C5F66;
      --white: #FFFFFF;
      --border-light: rgba(0,0,0,0.06);
      --shadow-sm: 0 2px 8px rgba(0,0,0,0.04);
      --shadow-md: 0 8px 24px rgba(0,0,0,0.10);
      --radius-sm: 8px;
      --radius-md: 12px;
      --radius-pill: 50px;
      --transition: 0.25s ease;
      --container-max: 1280px;
      --font-stack: 'PingFang SC', 'Microsoft YaHei', system-ui, -apple-system, sans-serif;
    }
    
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    
    html {
      scroll-behavior: smooth;
    }
    
    body {
      font-family: var(--font-stack);
      background-color: var(--white);
      color: var(--text-main);
      line-height: 1.75;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
    }
    
    .container {
      max-width: var(--container-max);
      margin: 0 auto;
      padding: 0 24px;
    }
    
    img {
      max-width: 100%;
      height: auto;
      display: block;
    }
    
    a {
      text-decoration: none;
      color: inherit;
      transition: color var(--transition);
    }
    
    button, input, textarea {
      font-family: inherit;
      font-size: inherit;
    }
    
    /* ----- 导航栏（桌面端沉浸式） ----- */
    .site-header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 1000;
      transition: background var(--transition), backdrop-filter var(--transition);
      padding: 16px 0;
    }
    
    .site-header.scrolled {
      background: rgba(26, 29, 35, 0.85);
      backdrop-filter: blur(12px);
      box-shadow: 0 4px 20px rgba(0,0,0,0.15);
    }
    
    .header-inner {
      display: flex;
      align-items: center;
      justify-content: space-between;
      max-width: var(--container-max);
      margin: 0 auto;
      padding: 0 24px;
    }
    
    .logo {
      font-size: 24px;
      font-weight: 700;
      color: var(--white);
      letter-spacing: 1px;
      display: flex;
      align-items: center;
      gap: 8px;
    }
    .logo i {
      color: var(--accent);
      font-size: 28px;
    }
    .scrolled .logo {
      color: var(--white);
    }
    
    .nav-links {
      display: flex;
      gap: 36px;
      align-items: center;
      list-style: none;
    }
    
    .nav-links a {
      color: rgba(255,255,255,0.9);
      font-weight: 500;
      font-size: 15px;
      position: relative;
      padding: 4px 0;
      transition: color var(--transition);
    }
    
    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: -6px;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--accent);
      transition: width var(--transition);
    }
    
    .nav-links a:hover,
    .nav-links a.active {
      color: var(--white);
    }
    
    .nav-links a:hover::after,
    .nav-links a.active::after {
      width: 100%;
    }
    
    /* 移动端底部胶囊导航（默认隐藏） */
    .mobile-bottom-nav {
      display: none;
      position: fixed;
      bottom: 0;
      left: 0;
      width: 100%;
      background: rgba(26, 29, 35, 0.95);
      backdrop-filter: blur(20px);
      padding: 8px 20px;
      z-index: 1001;
      border-top: 1px solid rgba(255,255,255,0.1);
      justify-content: space-around;
    }
    
    .mobile-nav-item {
      display: flex;
      flex-direction: column;
      align-items: center;
      color: rgba(255,255,255,0.6);
      font-size: 12px;
      gap: 4px;
      transition: color var(--transition);
    }
    
    .mobile-nav-item i {
      font-size: 20px;
    }
    
    .mobile-nav-item.active {
      color: var(--accent);
    }
    
    /* ----- 板块通用样式 ----- */
    section {
      padding: 100px 0;
    }
    
    .section-title {
      font-size: 36px;
      font-weight: 700;
      margin-bottom: 16px;
      color: var(--text-main);
      letter-spacing: -0.5px;
    }
    
    .section-desc {
      font-size: 18px;
      color: var(--text-secondary);
      margin-bottom: 48px;
      max-width: 700px;
    }
    
    /* ----- Hero 首屏 ----- */
    .hero {
      background-color: var(--dark-bg);
      background-image: url('/assets/images/backpic/back-1.webp');
      background-size: cover;
      background-position: center;
      min-height: 100vh;
      display: flex;
      align-items: center;
      position: relative;
      overflow: hidden;
      padding: 120px 0 80px;
    }
    
    .hero::before {
      content: '';
      position: absolute;
      inset: 0;
      background: linear-gradient(135deg, rgba(26,29,35,0.85) 0%, rgba(26,29,35,0.7) 100%);
      z-index: 1;
    }
    
    .hero .container {
      position: relative;
      z-index: 2;
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 60px;
      align-items: center;
    }
    
    .hero-content h1 {
      font-size: 56px;
      font-weight: 700;
      line-height: 1.2;
      color: var(--white);
      margin-bottom: 24px;
    }
    
    .hero-content .subtitle {
      font-size: 20px;
      color: rgba(255,255,255,0.8);
      margin-bottom: 40px;
      max-width: 500px;
    }
    
    .hero-buttons {
      display: flex;
      gap: 20px;
      flex-wrap: wrap;
    }
    
    .btn {
      display: inline-flex;
      align-items: center;
      gap: 8px;
      padding: 14px 32px;
      border-radius: var(--radius-sm);
      font-weight: 600;
      transition: all var(--transition);
      cursor: pointer;
      border: none;
      font-size: 16px;
    }
    
    .btn-primary {
      background: var(--primary);
      color: var(--white);
    }
    
    .btn-primary:hover {
      background: var(--primary-hover);
      transform: translateX(4px);
    }
    
    .btn-outline {
      background: transparent;
      border: 2px solid var(--primary);
      color: var(--white);
    }
    
    .btn-outline:hover {
      background: var(--primary-light);
      color: var(--primary);
      border-color: var(--primary-light);
    }
    
    .btn-accent {
      background: var(--accent);
      color: var(--dark-bg);
    }
    
    .btn-accent:hover {
      background: var(--accent-hover);
    }
    
    /* Hero 右侧浮动数据卡片 */
    .data-cards-float {
      display: flex;
      flex-direction: column;
      gap: 20px;
      position: relative;
    }
    
    .float-card {
      background: rgba(255,255,255,0.06);
      backdrop-filter: blur(10px);
      border: 1px solid rgba(255,255,255,0.12);
      border-radius: var(--radius-md);
      padding: 20px;
      color: var(--white);
      width: fit-content;
      align-self: flex-end;
      transition: transform var(--transition);
    }
    
    .float-card:nth-child(2) {
      align-self: flex-start;
      margin-left: 40px;
    }
    
    .float-card .metric {
      font-size: 32px;
      font-weight: 700;
      color: var(--accent);
      display: flex;
      align-items: baseline;
      gap: 4px;
    }
    
    .float-card .label {
      font-size: 14px;
      color: rgba(255,255,255,0.7);
    }
    
    /* ----- 核心数据看板 ----- */
    .data-dashboard {
      background: var(--dark-bg);
      color: var(--white);
    }
    
    .dashboard-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 40px;
      text-align: center;
    }
    
    .stat-item .stat-number {
      font-size: 48px;
      font-weight: 700;
      color: var(--accent);
      font-variant-numeric: tabular-nums;
    }
    
    .stat-item .stat-label {
      font-size: 18px;
      color: rgba(255,255,255,0.7);
      margin: 8px 0;
    }
    
    .trend-bar {
      height: 8px;
      background: rgba(255,255,255,0.1);
      border-radius: 4px;
      width: 80%;
      margin: 16px auto 0;
      overflow: hidden;
    }
    
    .trend-fill {
      height: 100%;
      background: var(--accent);
      width: 78%;
      border-radius: 4px;
    }
    
    /* ----- 服务矩阵（非对称四列） ----- */
    .service-grid {
      display: grid;
      grid-template-columns: 1.2fr 1fr 1fr 1fr;
      gap: 24px;
    }
    
    .service-card {
      background: var(--warm-gray);
      border-radius: var(--radius-md);
      padding: 32px 24px;
      transition: all var(--transition);
      cursor: pointer;
      border-left: 3px solid transparent;
    }
    
    .service-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-md);
      border-left: 3px solid var(--primary);
    }
    
    .service-icon {
      font-size: 40px;
      color: var(--accent);
      margin-bottom: 20px;
    }
    
    .service-card h3 {
      font-size: 20px;
      font-weight: 600;
      margin-bottom: 12px;
    }
    
    .service-card p {
      color: var(--text-secondary);
      margin-bottom: 20px;
      font-size: 15px;
    }
    
    .service-metric {
      font-weight: 700;
      color: var(--primary);
      font-size: 18px;
    }
    
    .text-link {
      color: var(--primary);
      font-weight: 600;
      display: inline-flex;
      align-items: center;
      gap: 4px;
    }
    
    /* ----- 技术对比（Before/After） ----- */
    .comparison-wrapper {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 40px;
      align-items: center;
    }
    
    .compare-col {
      padding: 40px;
      border-radius: var(--radius-md);
    }
    
    .compare-col.old {
      background: #f0f0f0;
      color: #888;
    }
    
    .compare-col.new {
      background: var(--white);
      border: 2px solid var(--primary);
      box-shadow: var(--shadow-sm);
    }
    
    .compare-col h3 {
      font-size: 24px;
      margin-bottom: 24px;
      display: flex;
      align-items: center;
      gap: 12px;
    }
    
    .compare-list {
      list-style: none;
    }
    
    .compare-list li {
      margin-bottom: 16px;
      display: flex;
      align-items: center;
      gap: 12px;
    }
    
    .old .compare-list li::before {
      content: '✕';
      color: #999;
    }
    
    .new .compare-list li::before {
      content: '✓';
      color: var(--accent);
      font-weight: bold;
    }
    
    /* ----- 合作伙伴跑马灯 ----- */
    .partners {
      background: var(--warm-gray);
    }
    
    .marquee {
      display: flex;
      gap: 60px;
      justify-content: center;
      flex-wrap: wrap;
      align-items: center;
    }
    
    .partner-logo {
      font-size: 24px;
      font-weight: 700;
      color: #aaa;
      transition: color var(--transition);
      filter: grayscale(1);
    }
    
    .partner-logo:hover {
      color: var(--text-main);
      filter: grayscale(0);
    }
    
    /* ----- FAQ 手风琴三列 ----- */
    .faq-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 40px;
    }
    
    .faq-group h4 {
      font-size: 20px;
      margin-bottom: 24px;
      color: var(--primary);
    }
    
    .faq-item {
      border-bottom: 1px solid var(--border-light);
      padding: 16px 0;
    }
    
    .faq-question {
      font-weight: 600;
      cursor: pointer;
      display: flex;
      justify-content: space-between;
      align-items: center;
    }
    
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease;
      color: var(--text-secondary);
      font-size: 15px;
      background: var(--warm-gray);
      border-radius: 0 0 var(--radius-sm) var(--radius-sm);
      padding: 0 12px;
    }
    
    .faq-item.open .faq-answer {
      max-height: 150px;
      padding: 12px;
      margin-top: 8px;
    }
    
    .faq-item.open .faq-question {
      color: var(--primary);
    }
    
    /* ----- 最终转化表单 ----- */
    .cta-form {
      background: var(--dark-bg);
      background-image: url('/assets/images/backpic/back-2.webp');
      background-size: cover;
      background-position: center;
      position: relative;
    }
    
    .cta-form::before {
      content: '';
      position: absolute;
      inset: 0;
      background: rgba(26,29,35,0.9);
    }
    
    .cta-form .container {
      position: relative;
      z-index: 2;
      text-align: center;
    }
    
    .cta-form h2 {
      color: var(--white);
      font-size: 36px;
      margin-bottom: 40px;
    }
    
    .form-row {
      display: flex;
      gap: 20px;
      justify-content: center;
      flex-wrap: wrap;
    }
    
    .form-input {
      padding: 14px 20px;
      border-radius: var(--radius-sm);
      border: none;
      background: var(--white);
      min-width: 220px;
      outline: none;
      transition: box-shadow var(--transition);
    }
    
    .form-input:focus {
      box-shadow: 0 0 0 3px var(--accent);
    }
    
    /* ----- 页脚 ----- */
    .site-footer {
      background: var(--dark-bg);
      color: rgba(255,255,255,0.7);
      padding: 60px 0 30px;
    }
    
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 40px;
      margin-bottom: 40px;
    }
    
    .footer-col h5 {
      color: var(--white);
      margin-bottom: 20px;
      font-size: 16px;
    }
    
    .footer-col ul {
      list-style: none;
    }
    
    .footer-col li {
      margin-bottom: 12px;
    }
    
    .footer-col a:hover {
      color: var(--accent);
    }
    
    .copyright {
      border-top: 1px solid rgba(255,255,255,0.1);
      padding-top: 24px;
      display: flex;
      justify-content: space-between;
      font-size: 14px;
    }
    
    /* ----- 响应式设计 ----- */
    @media (max-width: 1024px) {
      .hero .container {
        grid-template-columns: 1fr;
      }
      .data-cards-float {
        flex-direction: row;
        justify-content: center;
      }
      .service-grid {
        grid-template-columns: 1fr 1fr;
      }
      .comparison-wrapper {
        grid-template-columns: 1fr;
      }
    }
    
    @media (max-width: 768px) {
      .desktop-nav {
        display: none;
      }
      .mobile-bottom-nav {
        display: flex;
      }
      .hero-content h1 {
        font-size: 40px;
      }
      .dashboard-grid {
        grid-template-columns: 1fr;
      }
      .service-grid {
        grid-template-columns: 1fr;
      }
      .faq-grid {
        grid-template-columns: 1fr;
      }
      .footer-grid {
        grid-template-columns: 1fr 1fr;
      }
      section {
        padding: 60px 0;
      }
      .form-row {
        flex-direction: column;
        align-items: center;
      }
      .form-input {
        width: 100%;
        max-width: 320px;
      }
    }
    
    @media (max-width: 520px) {
      .hero-buttons {
        flex-direction: column;
      }
      .footer-grid {
        grid-template-columns: 1fr;
      }
      .copyright {
        flex-direction: column;
        gap: 8px;
        text-align: center;
      }
    }