/* roulang page: index */
:root {
      --primary: #A855F7;
      --primary-glow: rgba(168,85,247,0.6);
      --primary-soft: rgba(168,85,247,0.15);
      --accent: #00F0FF;
      --accent-soft: rgba(0,240,255,0.15);
      --bg-deep: #0B0D17;
      --bg-card: #161923;
      --bg-card-hover: #1e212e;
      --text-main: #ffffff;
      --text-secondary: #b0b3c1;
      --text-muted: #6b6f80;
      --border-light: rgba(168,85,247,0.15);
      --border-active: #A855F7;
      --border-accent: #00F0FF;
      --radius-sm: 8px;
      --radius: 12px;
      --radius-lg: 16px;
      --shadow-glow: 0 0 20px rgba(168,85,247,0.5);
      --font-mono: 'JetBrains Mono', 'Courier New', monospace;
      --font-sans: 'Inter', system-ui, -apple-system, sans-serif;
      --transition: 0.25s ease;
      --container-max: 1280px;
      --section-padding: 100px 24px;
    }

    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }

    html {
      scroll-behavior: smooth;
      background-color: var(--bg-deep);
    }

    body {
      font-family: var(--font-sans);
      background: var(--bg-deep);
      color: var(--text-main);
      line-height: 1.7;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
    }

    img {
      max-width: 100%;
      height: auto;
      display: block;
    }

    a {
      text-decoration: none;
      color: inherit;
      transition: var(--transition);
    }

    button, input, textarea {
      font-family: inherit;
      outline: none;
    }

    .container {
      max-width: var(--container-max);
      margin: 0 auto;
      padding: 0 24px;
    }

    /* 导航 */
    #nav {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      background: rgba(11,13,23,0.85);
      backdrop-filter: blur(14px);
      -webkit-backdrop-filter: blur(14px);
      border-bottom: 1px solid var(--border-light);
      z-index: 1000;
      padding: 0 24px;
      display: flex;
      align-items: center;
      justify-content: space-between;
      height: 68px;
      transition: background 0.2s;
    }

    .logo {
      font-weight: 700;
      font-size: 1.4rem;
      letter-spacing: -0.3px;
      color: var(--text-main);
      display: flex;
      align-items: center;
      gap: 6px;
    }

    .logo span {
      color: var(--primary);
      font-weight: 800;
    }

    .nav-links {
      display: flex;
      align-items: center;
      gap: 32px;
      list-style: none;
    }

    .nav-links a {
      font-size: 0.95rem;
      font-weight: 500;
      color: var(--text-secondary);
      position: relative;
    }

    .nav-links a:hover,
    .nav-links a.active {
      color: white;
    }

    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: -6px;
      left: 0;
      width: 0%;
      height: 2px;
      background: var(--primary);
      transition: width 0.2s ease;
    }

    .nav-links a:hover::after {
      width: 100%;
    }

    .nav-cta {
      background: var(--primary);
      color: white;
      padding: 10px 20px;
      border-radius: var(--radius-sm);
      font-weight: 600;
      font-size: 0.9rem;
      transition: var(--transition);
      border: none;
      cursor: pointer;
    }

    .nav-cta:hover {
      background: #b86efc;
      box-shadow: var(--shadow-glow);
    }

    .hamburger {
      display: none;
      flex-direction: column;
      gap: 5px;
      cursor: pointer;
      background: transparent;
      border: none;
    }

    .hamburger span {
      width: 24px;
      height: 2px;
      background: white;
      transition: 0.2s;
    }

    /* 移动端菜单 */
    .mobile-menu {
      display: none;
      position: fixed;
      top: 68px;
      left: 0;
      width: 100%;
      background: rgba(11,13,23,0.96);
      backdrop-filter: blur(20px);
      padding: 32px 24px;
      flex-direction: column;
      gap: 24px;
      z-index: 999;
      border-bottom: 1px solid var(--border-light);
    }

    .mobile-menu a {
      font-size: 1.2rem;
      font-weight: 500;
      color: var(--text-secondary);
    }

    /* Hero */
    #hero {
      padding: 140px 24px 100px;
      background: radial-gradient(circle at 30% 40%, #2d1b4e 0%, #0B0D17 75%);
      position: relative;
      display: flex;
      align-items: center;
      min-height: 90vh;
    }

    .hero-grid {
      display: flex;
      align-items: center;
      gap: 48px;
      flex-wrap: wrap;
    }

    .hero-content {
      flex: 1 1 500px;
    }

    .hero-content h1 {
      font-size: 3.5rem;
      font-weight: 800;
      line-height: 1.2;
      margin-bottom: 24px;
    }

    .hero-content .lead {
      font-size: 1.3rem;
      color: var(--text-secondary);
      margin-bottom: 36px;
    }

    .hero-buttons {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }

    .btn-primary {
      background: var(--primary);
      color: white;
      padding: 14px 32px;
      border-radius: var(--radius-sm);
      font-weight: 600;
      border: none;
      cursor: pointer;
      transition: var(--transition);
    }

    .btn-primary:hover {
      background: #b86efc;
      box-shadow: 0 0 24px var(--primary-glow);
    }

    .btn-secondary {
      background: transparent;
      border: 1px solid var(--primary);
      color: var(--primary);
      padding: 14px 32px;
      border-radius: var(--radius-sm);
      font-weight: 600;
      cursor: pointer;
      transition: var(--transition);
    }

    .btn-secondary:hover {
      background: rgba(168,85,247,0.1);
    }

    .hero-visual {
      flex: 1 1 400px;
      background-image: url('/assets/images/backpic/back-1.webp');
      background-size: cover;
      background-position: center;
      border-radius: var(--radius-lg);
      min-height: 350px;
      box-shadow: 0 0 30px rgba(168,85,247,0.3);
    }

    /* 通用 section */
    section {
      padding: var(--section-padding);
    }

    .section-title {
      font-size: 2.25rem;
      font-weight: 700;
      margin-bottom: 16px;
      display: flex;
      align-items: center;
      gap: 12px;
    }

    .section-title::before {
      content: '';
      width: 6px;
      height: 30px;
      background: var(--accent);
      border-radius: 3px;
    }

    .section-sub {
      color: var(--text-secondary);
      margin-bottom: 48px;
      font-size: 1.1rem;
    }

    /* 实时数据 */
    #live-data {
      background: #0e101a;
    }

    .data-grid {
      display: grid;
      grid-template-columns: repeat(5, 1fr);
      gap: 24px;
    }

    .data-card {
      background: transparent;
      text-align: center;
      padding: 28px 12px;
      border-bottom: 2px solid rgba(168,85,247,0.25);
    }

    .data-number {
      font-family: var(--font-mono);
      font-size: 2.5rem;
      font-weight: 700;
      color: var(--accent);
    }

    .data-label {
      color: var(--text-secondary);
      margin-top: 8px;
    }

    /* 服务卡片 */
    .cards-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }

    .service-card {
      background: var(--bg-card);
      border: 1px solid var(--border-light);
      border-radius: var(--radius);
      padding: 32px 24px;
      transition: var(--transition);
    }

    .service-card:hover {
      border-color: var(--primary);
      transform: translateY(-4px);
      background: var(--bg-card-hover);
    }

    .card-icon {
      font-size: 2rem;
      color: var(--accent);
      margin-bottom: 20px;
    }

    .card-title {
      font-size: 1.25rem;
      font-weight: 600;
      margin-bottom: 12px;
    }

    /* 优势 */
    .advantage-row {
      display: flex;
      gap: 48px;
      align-items: center;
      margin-bottom: 60px;
    }

    .advantage-stat {
      font-family: var(--font-mono);
      font-size: 3rem;
      font-weight: 700;
      color: var(--accent);
    }

    /* 案例 */
    .case-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }

    .case-card {
      position: relative;
      overflow: hidden;
      border-radius: var(--radius);
    }

    .case-card img {
      width: 100%;
      height: 220px;
      object-fit: cover;
    }

    .case-overlay {
      position: absolute;
      top: 0; left: 0; right: 0; bottom: 0;
      background: rgba(168,85,247,0.8);
      color: white;
      display: flex;
      align-items: center;
      justify-content: center;
      opacity: 0;
      transition: 0.3s;
    }

    .case-card:hover .case-overlay {
      opacity: 1;
    }

    /* 方案对比 */
    .compare-grid {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 32px;
    }

    .plan-card {
      background: var(--bg-card);
      border-radius: var(--radius);
      padding: 36px 28px;
    }

    .plan-highlight {
      border: 1px solid var(--primary);
    }

    /* FAQ */
    .faq-list {
      max-width: 800px;
      margin: 0 auto;
    }

    .faq-item {
      border-bottom: 1px solid var(--border-light);
      padding: 18px 0;
      cursor: pointer;
    }

    .faq-question {
      font-weight: 600;
      display: flex;
      justify-content: space-between;
    }

    .faq-answer {
      margin-top: 12px;
      color: var(--text-secondary);
      display: none;
    }

    .faq-item.open .faq-answer {
      display: block;
    }

    .faq-item.open .faq-question {
      color: var(--primary);
    }

    /* 联系表单 */
    .form-row {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }

    .form-input {
      flex: 1;
      background: #1a1d2b;
      border: 1px solid #2d3040;
      padding: 14px;
      border-radius: var(--radius-sm);
      color: white;
    }

    .form-input:focus {
      border-color: var(--primary);
    }

    /* 页脚 */
    #footer {
      background: #080a0f;
      padding: 60px 24px 30px;
    }

    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 32px;
    }

    @media (max-width: 1024px) {
      .data-grid { grid-template-columns: repeat(3, 1fr); }
      .cards-grid { grid-template-columns: 1fr 1fr; }
      .case-grid { grid-template-columns: 1fr 1fr; }
      .compare-grid { grid-template-columns: 1fr; }
    }

    @media (max-width: 768px) {
      .nav-links { display: none; }
      .hamburger { display: flex; }
      #hero { padding: 120px 20px 60px; }
      .hero-content h1 { font-size: 2rem; }
      .data-grid { grid-template-columns: 1fr 1fr; }
      .cards-grid { grid-template-columns: 1fr; }
      .advantage-row { flex-direction: column; }
      .case-grid { grid-template-columns: 1fr; }
      .footer-grid { grid-template-columns: 1fr; }
      .btn-primary, .btn-secondary { width: 100%; text-align: center; }
    }