/* roulang page: index */
:root {
      --primary-dark: #0A0E27;
      --accent-cyan: #00F0FF;
      --accent-red: #FF4655;
      --bg-light: #FAFAFC;
      --card-bg: #FFFFFF;
      --border-light: #E8ECF1;
      --text-primary: #1A1E2B;
      --text-secondary: #5A5F72;
      --text-on-dark: #F0F2F5;
      --text-muted: #8B8FA3;
      
      --font-heading: "PingFang SC", "Microsoft YaHei", "Noto Sans SC", sans-serif;
      --font-mono: "Inter", "Roboto", system-ui, sans-serif;
      
      --radius-sm: 8px;
      --radius-md: 12px;
      --radius-lg: 20px;
      
      --shadow-card: 0 2px 8px rgba(10,14,39,0.04);
      --shadow-hover: 0 8px 24px rgba(0,240,255,0.12);
      --shadow-button: 0 0 20px rgba(0,240,255,0.5);
      
      --container-max: 1280px;
      --section-gap: 100px;
    }
    
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    
    body {
      font-family: var(--font-heading);
      background-color: var(--bg-light);
      color: var(--text-primary);
      line-height: 1.7;
      font-size: 15px;
      -webkit-font-smoothing: antialiased;
      overflow-x: hidden;
    }
    
    .container {
      max-width: var(--container-max);
      margin: 0 auto;
      padding: 0 24px;
    }
    
    /* 排版辅助 */
    h1, h2, h3, h4 {
      font-family: var(--font-heading);
      font-weight: 700;
      letter-spacing: -0.3px;
    }
    
    h1 {
      font-size: 48px;
      line-height: 1.2;
      letter-spacing: -0.5px;
    }
    
    h2 {
      font-size: 36px;
      line-height: 1.3;
      margin-bottom: 16px;
    }
    
    h3 {
      font-size: 20px;
      font-weight: 600;
      line-height: 1.4;
    }
    
    .section-title {
      text-align: center;
      margin-bottom: 48px;
    }
    
    .section-title h2 {
      color: var(--primary-dark);
    }
    
    .text-on-dark .section-title h2 {
      color: white;
    }
    
    p {
      color: var(--text-secondary);
      font-size: 15px;
      line-height: 1.7;
    }
    
    a {
      text-decoration: none;
      color: inherit;
      transition: all 0.25s ease;
    }
    
    img {
      max-width: 100%;
      display: block;
    }
    
    /* 按钮系统 */
    .btn {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      padding: 14px 32px;
      border-radius: var(--radius-sm);
      font-weight: 600;
      font-size: 15px;
      cursor: pointer;
      transition: all 0.3s ease;
      border: 2px solid transparent;
      min-width: 140px;
      text-align: center;
      letter-spacing: 0.3px;
    }
    
    .btn-primary {
      background-color: var(--accent-cyan);
      color: var(--primary-dark);
      border-color: var(--accent-cyan);
    }
    
    .btn-primary:hover {
      background-color: #00e0f0;
      box-shadow: var(--shadow-button);
      transform: translateY(-2px);
    }
    
    .btn-secondary {
      background: transparent;
      color: var(--accent-cyan);
      border: 2px solid var(--accent-cyan);
    }
    
    .btn-secondary:hover {
      background: var(--accent-cyan);
      color: var(--primary-dark);
    }
    
    .btn-ghost {
      background: transparent;
      color: white;
      border: 2px solid rgba(255,255,255,0.5);
    }
    
    .btn-ghost:hover {
      border-color: var(--accent-cyan);
      color: var(--accent-cyan);
    }
    
    /* 导航 */
    .site-header {
      position: sticky;
      top: 0;
      z-index: 100;
      background: rgba(255,255,255,0.92);
      backdrop-filter: blur(12px);
      border-bottom: 1px solid var(--border-light);
    }
    
    .nav-container {
      display: flex;
      align-items: center;
      justify-content: space-between;
      max-width: var(--container-max);
      margin: 0 auto;
      padding: 0 24px;
      height: 72px;
    }
    
    .logo {
      font-size: 24px;
      font-weight: 800;
      background: linear-gradient(135deg, #00F0FF 0%, #0A0E27 80%);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
      letter-spacing: -0.5px;
      white-space: nowrap;
      order: 2;
      text-decoration: none;
    }
    
    .nav-left, .nav-right {
      display: flex;
      gap: 32px;
      align-items: center;
      list-style: none;
    }
    
    .nav-left {
      order: 1;
    }
    
    .nav-right {
      order: 3;
    }
    
    .nav-link {
      font-size: 15px;
      font-weight: 500;
      color: var(--text-primary);
      position: relative;
      padding: 8px 0;
      transition: color 0.2s;
    }
    
    .nav-link::after {
      content: '';
      position: absolute;
      bottom: 0;
      left: 50%;
      width: 0;
      height: 2px;
      background: var(--accent-cyan);
      transition: all 0.3s ease;
      transform: translateX(-50%);
    }
    
    .nav-link:hover {
      color: var(--accent-cyan);
    }
    
    .nav-link:hover::after {
      width: 100%;
    }
    
    .hamburger {
      display: none;
      font-size: 24px;
      cursor: pointer;
      color: var(--primary-dark);
      order: 3;
      background: none;
      border: none;
    }
    
    /* 移动端菜单 */
    .mobile-menu {
      display: none;
      position: fixed;
      top: 72px;
      left: 0;
      width: 100%;
      height: calc(100vh - 72px);
      background: var(--primary-dark);
      flex-direction: column;
      padding: 40px 32px;
      gap: 24px;
      z-index: 99;
      transform: translateX(100%);
      transition: transform 0.4s ease;
    }
    
    .mobile-menu.active {
      transform: translateX(0);
      display: flex;
    }
    
    .mobile-menu a {
      color: white;
      font-size: 18px;
      font-weight: 500;
      padding: 12px 0;
      border-left: 3px solid transparent;
      padding-left: 16px;
      transition: 0.2s;
    }
    
    .mobile-menu a:hover {
      border-left-color: var(--accent-cyan);
      color: var(--accent-cyan);
    }
    
    /* Hero */
    #hero {
      background-color: var(--primary-dark);
      padding: 80px 0;
      color: white;
    }
    
    .hero-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 40px;
      align-items: center;
    }
    
    .hero-content h1 {
      color: white;
      margin-bottom: 20px;
    }
    
    .hero-subtitle {
      font-size: 18px;
      color: rgba(255,255,255,0.7);
      margin-bottom: 36px;
      max-width: 480px;
    }
    
    .hero-buttons {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }
    
    .hero-visual {
      background-image: url('/assets/images/backpic/back-1.webp');
      background-size: cover;
      background-position: center;
      border-radius: var(--radius-lg);
      height: 420px;
      position: relative;
      overflow: hidden;
      box-shadow: 0 20px 40px rgba(0,0,0,0.5);
    }
    
    .hero-visual::after {
      content: '';
      position: absolute;
      top: 0;
      left: 0;
      width: 100%;
      height: 100%;
      background: radial-gradient(circle at 30% 30%, rgba(0,240,255,0.25) 0%, transparent 70%);
    }
    
    /* 优势卡片 */
    #advantages {
      padding: var(--section-gap) 0;
    }
    
    .advantages-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 28px;
    }
    
    .advantage-card {
      background: var(--card-bg);
      border: 1px solid var(--border-light);
      border-radius: var(--radius-md);
      padding: 32px 24px;
      box-shadow: var(--shadow-card);
      transition: all 0.3s ease;
    }
    
    .advantage-card:hover {
      transform: translateY(-6px);
      box-shadow: var(--shadow-hover);
      border-color: var(--accent-cyan);
    }
    
    .advantage-icon {
      width: 48px;
      height: 48px;
      background: var(--accent-cyan);
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      margin-bottom: 20px;
      color: var(--primary-dark);
      font-size: 20px;
    }
    
    .advantage-card h3 {
      margin-bottom: 12px;
    }
    
    /* 产品 */
    #products {
      background: var(--primary-dark);
      padding: var(--section-gap) 0;
    }
    
    .products-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 24px;
    }
    
    .product-card {
      background: rgba(255,255,255,0.05);
      border: 1px solid rgba(255,255,255,0.1);
      border-radius: var(--radius-md);
      overflow: hidden;
      transition: 0.3s;
    }
    
    .product-card:hover {
      border-color: var(--accent-cyan);
      transform: translateY(-4px);
      box-shadow: 0 12px 28px rgba(0,240,255,0.15);
    }
    
    .product-img {
      height: 160px;
      background-size: cover;
      background-position: center;
    }
    
    .product-info {
      padding: 20px;
      color: white;
    }
    
    .product-info h3 {
      margin-bottom: 8px;
    }
    
    .product-tags {
      display: flex;
      gap: 8px;
      margin-top: 14px;
      flex-wrap: wrap;
    }
    
    .tag {
      background: var(--accent-red);
      color: white;
      font-size: 12px;
      padding: 4px 10px;
      border-radius: 20px;
      font-weight: 500;
    }
    
    /* 场景 */
    #scenarios {
      padding: var(--section-gap) 0;
    }
    
    .scenario-row {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 48px;
      align-items: center;
      margin-bottom: 80px;
    }
    
    .scenario-row:last-child {
      margin-bottom: 0;
    }
    
    .scenario-img {
      background-size: cover;
      background-position: center;
      border-radius: var(--radius-md);
      height: 300px;
      box-shadow: 0 8px 20px rgba(0,0,0,0.06);
    }
    
    .scenario-content h3 {
      margin-bottom: 16px;
    }
    
    .text-link {
      color: var(--accent-cyan);
      font-weight: 600;
      display: inline-block;
      margin-top: 12px;
      position: relative;
    }
    
    .text-link::after {
      content: '';
      position: absolute;
      bottom: -2px;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--accent-cyan);
      transition: 0.3s;
    }
    
    .text-link:hover::after {
      width: 100%;
    }
    
    /* 案例 */
    #cases {
      background: var(--primary-dark);
      padding: var(--section-gap) 0;
    }
    
    .stats-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 24px;
      margin-bottom: 60px;
    }
    
    .stat-item {
      text-align: center;
      color: white;
    }
    
    .stat-number {
      font-size: 48px;
      font-weight: 800;
      color: var(--accent-cyan);
      font-family: var(--font-mono);
    }
    
    .cases-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 28px;
    }
    
    .case-card {
      background: rgba(255,255,255,0.05);
      border-radius: var(--radius-md);
      padding: 28px;
      border: 1px solid rgba(255,255,255,0.1);
      color: white;
    }
    
    .case-logo {
      width: 64px;
      height: 64px;
      border-radius: 50%;
      border: 2px solid var(--accent-cyan);
      margin-bottom: 16px;
      background: rgba(255,255,255,0.1);
    }
    
    /* FAQ */
    #faq {
      padding: var(--section-gap) 0;
    }
    
    .faq-list {
      max-width: 800px;
      margin: 0 auto;
    }
    
    .faq-item {
      border: 1px solid var(--border-light);
      border-radius: var(--radius-sm);
      margin-bottom: 12px;
      background: white;
      transition: 0.2s;
    }
    
    .faq-question {
      padding: 18px 24px;
      font-weight: 600;
      display: flex;
      justify-content: space-between;
      align-items: center;
      cursor: pointer;
      font-size: 16px;
    }
    
    .faq-answer {
      padding: 0 24px 18px;
      display: none;
      color: var(--text-secondary);
    }
    
    .faq-item.active {
      border-color: var(--accent-cyan);
    }
    
    .faq-item.active .faq-answer {
      display: block;
    }
    
    /* CTA */
    #cta {
      background: var(--primary-dark);
      padding: 100px 0;
      text-align: center;
      color: white;
    }
    
    #cta h2 {
      color: white;
      margin-bottom: 16px;
    }
    
    .cta-buttons {
      display: flex;
      gap: 16px;
      justify-content: center;
      margin-top: 32px;
      flex-wrap: wrap;
    }
    
    /* Footer */
    #footer {
      background: #060A1A;
      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-logo {
      font-size: 22px;
      font-weight: 800;
      color: white;
      margin-bottom: 12px;
    }
    
    .footer-bottom {
      border-top: 1px solid rgba(255,255,255,0.1);
      padding-top: 24px;
      text-align: center;
      font-size: 14px;
    }
    
    @media (max-width: 1024px) {
      .products-grid { grid-template-columns: repeat(2, 1fr); }
      .stats-grid { grid-template-columns: repeat(2, 1fr); }
    }
    
    @media (max-width: 768px) {
      .nav-left, .nav-right { display: none; }
      .hamburger { display: block; }
      .logo { order: 1; margin-right: auto; }
      .nav-container { justify-content: space-between; }
      
      h1 { font-size: 32px; }
      h2 { font-size: 28px; }
      .section-gap { margin: 60px 0; }
      
      .hero-grid { grid-template-columns: 1fr; }
      .hero-visual { height: 240px; }
      .advantages-grid { grid-template-columns: 1fr; }
      .products-grid { grid-template-columns: 1fr; }
      .scenario-row { grid-template-columns: 1fr; }
      .cases-grid { grid-template-columns: 1fr; }
      .footer-grid { grid-template-columns: 1fr; }
    }