/* roulang page: index */
* {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    
    :root {
      --bg-deep: #0A0A14;
      --primary: #6C3CF0;
      --primary-glow: rgba(108, 60, 240, 0.5);
      --secondary: #00E5FF;
      --secondary-glow: rgba(0, 229, 255, 0.6);
      --accent: #FF2D78;
      --text-primary: #E8E6F0;
      --text-secondary: #9895AA;
      --card-bg: rgba(255, 255, 255, 0.03);
      --card-border: rgba(108, 60, 240, 0.24);
      --card-hover-border: rgba(0, 229, 255, 0.5);
      --border-light: rgba(108, 60, 240, 0.3);
      --radius-lg: 24px;
      --radius-md: 16px;
      --radius-sm: 12px;
      --radius-xs: 8px;
      --shadow-card: 0 8px 32px rgba(108, 60, 240, 0.08);
      --shadow-hover: 0 20px 40px rgba(0, 229, 255, 0.2);
      --container-max: 1280px;
      --header-height: 72px;
    }
    
    body {
      font-family: 'PingFang SC', 'Microsoft YaHei', 'Inter', sans-serif;
      background-color: var(--bg-deep);
      color: var(--text-primary);
      line-height: 1.8;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
      overflow-x: hidden;
    }
    
    .container {
      max-width: var(--container-max);
      margin: 0 auto;
      padding: 0 32px;
    }
    
    @media (max-width: 768px) {
      .container {
        padding: 0 20px;
      }
    }
    
    /* 排版 */
    h1, h2, h3, .h4 {
      font-weight: 700;
      letter-spacing: 0.5px;
    }
    h1 {
      font-size: 58px;
      line-height: 1.2;
    }
    h2 {
      font-size: 40px;
      line-height: 1.3;
      margin-bottom: 16px;
    }
    h3 {
      font-size: 24px;
      font-weight: 600;
      line-height: 1.4;
    }
    .section-title {
      position: relative;
      display: inline-block;
      margin-bottom: 40px;
    }
    .section-title .en-sub {
      display: block;
      font-family: 'Inter', sans-serif;
      font-size: 14px;
      font-weight: 400;
      color: var(--secondary);
      letter-spacing: 2px;
      text-transform: uppercase;
      margin-bottom: 8px;
    }
    
    a {
      color: var(--secondary);
      text-decoration: none;
      transition: color 0.25s;
    }
    a:hover {
      color: var(--primary);
    }
    
    button, .btn {
      cursor: pointer;
      font-family: inherit;
      border: none;
      background: transparent;
    }
    img {
      max-width: 100%;
      display: block;
    }
    
    /* 导航栏 */
    .header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: var(--header-height);
      background: rgba(10, 10, 20, 0.82);
      backdrop-filter: blur(20px);
      -webkit-backdrop-filter: blur(20px);
      z-index: 100;
      border-bottom: 1px solid rgba(108, 60, 240, 0.3);
      display: flex;
      align-items: center;
      transition: background 0.3s, box-shadow 0.3s;
    }
    .header.scrolled {
      background: rgba(10, 10, 20, 0.94);
      box-shadow: 0 4px 20px rgba(0,0,0,0.5);
    }
    
    .nav-container {
      display: flex;
      align-items: center;
      justify-content: space-between;
      width: 100%;
      max-width: var(--container-max);
      margin: 0 auto;
      padding: 0 32px;
    }
    .logo {
      display: flex;
      align-items: center;
      gap: 8px;
      font-weight: 700;
      font-size: 26px;
      color: white;
      letter-spacing: 1px;
    }
    .logo i {
      font-size: 28px;
      color: var(--secondary);
    }
    .nav-links {
      display: flex;
      gap: 36px;
      list-style: none;
    }
    .nav-links a {
      color: var(--text-primary);
      font-weight: 500;
      font-size: 16px;
      position: relative;
      transition: color 0.2s;
    }
    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: -6px;
      left: 0;
      width: 0%;
      height: 3px;
      background: var(--secondary);
      transition: width 0.25s ease;
      border-radius: 2px;
    }
    .nav-links a:hover::after,
    .nav-links a.active::after {
      width: 100%;
    }
    .nav-links a:hover,
    .nav-links a.active {
      color: var(--secondary);
    }
    
    .btn-primary {
      background: linear-gradient(135deg, var(--primary) 0%, #3B1F9E 100%);
      color: white;
      padding: 12px 28px;
      border-radius: var(--radius-sm);
      font-weight: 600;
      font-size: 16px;
      display: inline-flex;
      align-items: center;
      justify-content: center;
      gap: 8px;
      transition: all 0.3s cubic-bezier(0.25, 0.8, 0.25, 1.2);
      box-shadow: 0 4px 14px rgba(108,60,240,0.3);
      border: none;
    }
    .btn-primary:hover {
      transform: translateY(-3px);
      box-shadow: 0 12px 28px rgba(0,229,255,0.3);
      background: linear-gradient(135deg, #7B4CF0 0%, #4E2CB0 100%);
    }
    .btn-outline {
      background: transparent;
      border: 1.5px solid var(--secondary);
      color: var(--secondary);
      padding: 12px 28px;
      border-radius: var(--radius-sm);
      font-weight: 600;
      transition: all 0.3s ease;
    }
    .btn-outline:hover {
      background: rgba(0,229,255,0.08);
      border-color: #33ebff;
      box-shadow: 0 0 16px var(--secondary-glow);
      transform: translateY(-2px);
    }
    
    .hamburger {
      display: none;
      font-size: 28px;
      color: white;
    }
    
    @media (max-width: 1024px) {
      .nav-links {
        display: none;
      }
      .hamburger {
        display: block;
      }
    }
    
    /* 移动菜单 */
    .mobile-menu {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 100vh;
      background: rgba(10,10,20,0.96);
      backdrop-filter: blur(30px);
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: center;
      gap: 32px;
      z-index: 200;
      transform: translateX(100%);
      transition: transform 0.4s ease;
    }
    .mobile-menu.active {
      transform: translateX(0);
    }
    .mobile-menu a {
      font-size: 24px;
      color: #fff;
    }
    .close-menu {
      position: absolute;
      top: 24px;
      right: 32px;
      font-size: 36px;
      color: white;
    }
    
    /* Hero */
    .hero {
      min-height: 100vh;
      display: flex;
      align-items: center;
      position: relative;
      overflow: hidden;
      background: radial-gradient(circle at 30% 40%, rgba(108,60,240,0.18) 0%, rgba(10,10,20,1) 70%);
      padding-top: var(--header-height);
    }
    .hero-content {
      max-width: 800px;
      position: relative;
      z-index: 2;
    }
    .hero h1 {
      background: linear-gradient(to right, #fff, #c1b6ff);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      margin-bottom: 20px;
    }
    .hero .sub {
      font-size: 20px;
      color: var(--text-secondary);
      margin-bottom: 40px;
    }
    .cta-group {
      display: flex;
      gap: 20px;
      flex-wrap: wrap;
    }
    .stars-bg {
      position: absolute;
      top:0; left:0; width:100%; height:100%;
      pointer-events: none;
    }
    @media (max-width: 768px) {
      h1 { font-size: 40px; }
    }
    
    /* 板块间距 */
    section {
      padding: 130px 0;
    }
    
    /* 优势卡片不对称 */
    .advantages-grid {
      display: grid;
      grid-template-columns: 1fr 0.9fr;
      gap: 32px;
    }
    .advantages-grid .adv-card:first-child {
      grid-row: span 2;
    }
    .adv-card {
      background: var(--card-bg);
      border: 1px solid var(--card-border);
      border-radius: var(--radius-lg);
      padding: 40px 32px;
      backdrop-filter: blur(8px);
      transition: all 0.35s;
    }
    .adv-card:hover {
      border-color: var(--card-hover-border);
      box-shadow: var(--shadow-hover);
      transform: translateY(-8px);
    }
    @media (max-width: 768px) {
      .advantages-grid {
        grid-template-columns: 1fr;
      }
    }
    
    /* 服务卡片 2x3 */
    .services-grid {
      display: grid;
      grid-template-columns: repeat(3,1fr);
      gap: 28px;
      margin-top: 40px;
    }
    .service-card {
      background: var(--card-bg);
      border: 1px solid var(--card-border);
      border-radius: var(--radius-md);
      padding: 32px 24px;
      transition: 0.3s;
    }
    .service-card:hover {
      border-color: var(--secondary);
      box-shadow: 0 12px 36px rgba(0,229,255,0.25);
      transform: translateY(-8px);
    }
    @media (max-width: 1024px) {
      .services-grid { grid-template-columns: repeat(2,1fr); }
    }
    @media (max-width: 640px) {
      .services-grid { grid-template-columns: 1fr; }
    }
    
    /* 数据条 */
    .stats-bar {
      display: flex;
      justify-content: space-around;
      flex-wrap: wrap;
      gap: 30px;
    }
    .stat-item .number {
      font-family: 'Inter', sans-serif;
      font-size: 52px;
      font-weight: 700;
      color: var(--secondary);
    }
     
    /* FAQ */
    .faq-item {
      background: rgba(255,255,255,0.02);
      border:1px solid var(--card-border);
      border-radius: var(--radius-md);
      margin-bottom: 16px;
      padding: 20px 28px;
    }
    
    .footer {
      background: #06060f;
      padding: 60px 0 30px;
    }
    
    /* 动画工具 */
    .fade-up {
      opacity: 0;
      transform: translateY(40px);
      transition: opacity 0.7s ease, transform 0.7s ease;
    }
    .fade-up.visible {
      opacity: 1;
      transform: translateY(0);
    }
    
    @media (max-width: 768px) {
      section { padding: 90px 0; }
    }