/* roulang page: index */
:root {
      --deep-blue: #0B1A2E;
      --cyan: #00E5FF;
      --amber: #FFB300;
      --text-light: #B0C4DE;
      --text-dim: #7B8FA8;
      --white: #FFFFFF;
      --card-bg: rgba(255,255,255,0.03);
      --card-border: rgba(0,229,255,0.12);
      --card-hover-border: rgba(0,229,255,0.35);
      --glass-blur: blur(12px);
      --radius-lg: 20px;
      --radius-md: 16px;
      --radius-sm: 8px;
      --radius-btn: 30px;
      --shadow-card: 0 8px 32px rgba(0,0,0,0.4), 0 0 0 1px rgba(0,229,255,0.08) inset;
      --shadow-glow: 0 0 20px rgba(0,229,255,0.5);
      --shadow-glow-hover: 0 0 35px rgba(0,229,255,0.8);
      --section-gap: 120px;
      --section-gap-tablet: 80px;
      --section-gap-mobile: 60px;
    }
    * {
      box-sizing: border-box;
      margin: 0;
      padding: 0;
    }
    body {
      background-color: var(--deep-blue);
      font-family: "PingFang SC", "Microsoft YaHei", "Noto Sans SC", "Inter", "SF Pro Display", sans-serif;
      color: var(--text-light);
      line-height: 1.75;
      font-size: 1rem;
      -webkit-font-smoothing: antialiased;
      position: relative;
      overflow-x: hidden;
    }
    body::before {
      content: "";
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 100%;
      background-image: 
        linear-gradient(rgba(0,229,255,0.03) 1px, transparent 1px),
        linear-gradient(90deg, rgba(0,229,255,0.03) 1px, transparent 1px);
      background-size: 40px 40px;
      pointer-events: none;
      z-index: 0;
    }
    body::after {
      content: "";
      position: fixed;
      bottom: 0;
      right: 0;
      width: 600px;
      height: 600px;
      background: radial-gradient(circle at 80% 100%, rgba(0,229,255,0.08) 0%, transparent 70%);
      pointer-events: none;
      z-index: 0;
    }
    .container {
      max-width: 1200px;
      margin: 0 auto;
      padding: 0 20px;
      position: relative;
      z-index: 2;
    }
    h1, h2, h3, h4 {
      color: var(--white);
      font-weight: 600;
      margin-bottom: 0.75rem;
    }
    h1 {
      font-size: 3.2rem;
      font-weight: 700;
      letter-spacing: -0.02em;
      line-height: 1.2;
    }
    h2 {
      font-size: 2.2rem;
      font-weight: 600;
    }
    h3 {
      font-size: 1.5rem;
      font-weight: 600;
    }
    p {
      color: var(--text-light);
      margin-bottom: 1rem;
    }
    a {
      color: var(--cyan);
      text-decoration: none;
      transition: color 0.25s ease, text-shadow 0.25s ease;
    }
    a:hover {
      color: var(--cyan);
      text-shadow: 0 0 8px rgba(0,229,255,0.4);
    }
    .text-dim {
      color: var(--text-dim);
    }
    .text-amber {
      color: var(--amber);
    }
    .btn {
      display: inline-block;
      font-weight: 600;
      border-radius: var(--radius-btn);
      padding: 14px 36px;
      transition: all 0.3s ease;
      text-align: center;
      cursor: pointer;
      border: none;
      font-size: 1rem;
      letter-spacing: 0.3px;
    }
    .btn-primary {
      background: var(--cyan);
      color: var(--deep-blue);
      box-shadow: var(--shadow-glow);
    }
    .btn-primary:hover {
      background: #33EAFF;
      box-shadow: var(--shadow-glow-hover);
      transform: scale(1.04);
      color: var(--deep-blue);
    }
    .btn-secondary {
      background: transparent;
      border: 1.5px solid var(--cyan);
      color: var(--cyan);
      box-shadow: none;
    }
    .btn-secondary:hover {
      background: rgba(0,229,255,0.1);
      box-shadow: 0 0 15px rgba(0,229,255,0.3);
      color: var(--cyan);
    }
    .glass-card {
      background: var(--card-bg);
      border: 1px solid var(--card-border);
      backdrop-filter: var(--glass-blur);
      -webkit-backdrop-filter: var(--glass-blur);
      border-radius: var(--radius-md);
      box-shadow: var(--shadow-card);
      transition: border 0.3s, box-shadow 0.3s, background 0.3s;
    }
    .glass-card:hover {
      border-color: var(--card-hover-border);
      box-shadow: 0 0 24px rgba(0,229,255,0.15), 0 8px 32px rgba(0,0,0,0.5);
      background: rgba(255,255,255,0.06);
    }
    .glow-number {
      font-size: 3rem;
      font-weight: 800;
      color: var(--amber);
      text-shadow: 0 0 18px rgba(255,179,0,0.5);
      font-family: "Inter", "SF Pro Display", sans-serif;
      line-height: 1.1;
    }
    .tag {
      display: inline-block;
      padding: 4px 14px;
      border-radius: 20px;
      font-size: 0.8rem;
      font-weight: 500;
      background: rgba(255,179,0,0.08);
      color: var(--amber);
      border: 1px solid rgba(255,179,0,0.25);
    }
    /* 导航栏 */
    .rb88-header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 100;
      background: rgba(11,26,46,0.85);
      backdrop-filter: blur(20px);
      -webkit-backdrop-filter: blur(20px);
      border-bottom: 1px solid rgba(0,229,255,0.1);
    }
    .rb88-nav {
      display: flex;
      align-items: center;
      justify-content: space-between;
      max-width: 1200px;
      margin: 0 auto;
      padding: 0 20px;
      height: 70px;
    }
    .logo {
      font-size: 1.8rem;
      font-weight: 700;
      color: var(--white);
      letter-spacing: -0.5px;
    }
    .logo span {
      color: var(--cyan);
    }
    .logo small {
      font-size: 0.8rem;
      font-weight: 400;
      color: var(--text-dim);
      margin-left: 8px;
    }
    .nav-links {
      display: flex;
      gap: 2rem;
      list-style: none;
      align-items: center;
      margin: 0;
    }
    .nav-links a {
      color: var(--text-light);
      font-weight: 500;
      font-size: 0.95rem;
      padding: 8px 0;
      border-bottom: 2px solid transparent;
      transition: color 0.2s, border-color 0.2s;
    }
    .nav-links a:hover,
    .nav-links a.active {
      color: var(--cyan);
      border-bottom-color: var(--cyan);
    }
    .menu-icon {
      display: none;
      font-size: 1.6rem;
      color: var(--cyan);
      cursor: pointer;
    }
    @media (max-width: 1024px) {
      .nav-links {
        gap: 1.2rem;
      }
    }
    @media (max-width: 768px) {
      .menu-icon {
        display: block;
      }
      .nav-links {
        display: none;
        position: absolute;
        top: 70px;
        left: 0;
        width: 100%;
        background: rgba(11,26,46,0.95);
        backdrop-filter: blur(20px);
        flex-direction: column;
        padding: 20px;
        gap: 1rem;
        border-bottom: 1px solid rgba(0,229,255,0.15);
      }
      .nav-links.show {
        display: flex;
      }
      .rb88-nav {
        justify-content: space-between;
      }
    }
    /* 区块间距 */
    section {
      padding: var(--section-gap) 0;
    }
    @media (max-width: 1024px) {
      section {
        padding: var(--section-gap-tablet) 0;
      }
      h1 {
        font-size: 2.5rem;
      }
      h2 {
        font-size: 1.9rem;
      }
      .glow-number {
        font-size: 2.5rem;
      }
    }
    @media (max-width: 640px) {
      section {
        padding: var(--section-gap-mobile) 0;
      }
      h1 {
        font-size: 2rem;
      }
      h2 {
        font-size: 1.7rem;
      }
      .btn {
        padding: 12px 24px;
        width: 100%;
        display: block;
        margin-bottom: 12px;
      }
      .glow-number {
        font-size: 2.2rem;
      }
    }
    /* Hero */
    #hero {
      min-height: 90vh;
      display: flex;
      align-items: center;
      padding-top: 100px;
      position: relative;
    }
    .hero-grid {
      display: flex;
      align-items: center;
      gap: 3rem;
      flex-wrap: wrap;
    }
    .hero-content {
      flex: 1 1 500px;
    }
    .hero-visual {
      flex: 1 1 400px;
      position: relative;
      min-height: 300px;
      background: url('/assets/images/backpic/back-1.webp') center/cover no-repeat;
      border-radius: var(--radius-lg);
      box-shadow: 0 0 40px rgba(0,229,255,0.2);
      opacity: 0.9;
      display: flex;
      align-items: center;
      justify-content: center;
    }
    .hero-visual::after {
      content: "";
      position: absolute;
      inset: 0;
      background: rgba(11,26,46,0.35);
      border-radius: var(--radius-lg);
    }
    .hero-stats {
      display: flex;
      gap: 2rem;
      margin: 2rem 0;
      flex-wrap: wrap;
    }
    .stat-item {
      text-align: left;
    }
    /* 卡片网格 */
    .card-grid {
      display: grid;
      grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
      gap: 2rem;
      margin-top: 2.5rem;
    }
    .feature-card {
      padding: 32px 24px;
      text-align: left;
    }
    .feature-icon {
      font-size: 2.4rem;
      color: var(--cyan);
      margin-bottom: 1.2rem;
    }
    /* 产品图文 */
    .product-row {
      display: flex;
      align-items: center;
      gap: 3rem;
      margin-bottom: 4rem;
      flex-wrap: wrap;
    }
    .product-row.reverse {
      flex-direction: row-reverse;
    }
    .product-text {
      flex: 1 1 400px;
    }
    .product-image {
      flex: 1 1 400px;
      background: rgba(0,229,255,0.05);
      border-radius: var(--radius-md);
      min-height: 280px;
      display: flex;
      align-items: center;
      justify-content: center;
      border: 1px solid var(--card-border);
      overflow: hidden;
    }
    .product-image img {
      max-width: 100%;
      height: auto;
      border-radius: var(--radius-md);
    }
    /* FAQ */
    .accordion-item {
      margin-bottom: 8px;
    }
    .accordion-title {
      background: rgba(255,255,255,0.02);
      border: 1px solid rgba(0,229,255,0.1);
      padding: 16px 20px;
      font-weight: 600;
      cursor: pointer;
      display: flex;
      justify-content: space-between;
      align-items: center;
      border-radius: var(--radius-sm);
      color: var(--white);
      transition: 0.2s;
    }
    .accordion-title:hover {
      border-color: var(--cyan);
      color: var(--cyan);
    }
    .accordion-content {
      padding: 0 20px 20px;
      background: rgba(255,255,255,0.02);
      border-left: 3px solid var(--cyan);
      margin-top: -4px;
      border-radius: 0 0 var(--radius-sm) var(--radius-sm);
      display: none;
      color: var(--text-light);
    }
    .accordion-item.active .accordion-content {
      display: block;
    }
    /* CTA */
    #cta {
      background: linear-gradient(135deg, rgba(0,229,255,0.05) 0%, rgba(11,26,46,0.9) 100%);
      text-align: center;
    }
    /* 页脚 */
    .footer-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 2rem;
      padding: 3rem 0;
      border-top: 1px solid rgba(0,229,255,0.18);
    }
    .footer-bottom {
      border-top: 1px solid rgba(255,255,255,0.05);
      padding: 1.5rem 0;
      text-align: center;
      color: var(--text-dim);
      font-size: 0.9rem;
    }
    @media (max-width: 768px) {
      .footer-grid {
        grid-template-columns: repeat(2, 1fr);
      }
    }
    @media (max-width: 480px) {
      .footer-grid {
        grid-template-columns: 1fr;
      }
    }