/* roulang page: index */
:root {
      --primary: #0A1A2F;
      --secondary: #1E3A5F;
      --accent: #00D4FF;
      --accent-glow: rgba(0,212,255,0.7);
      --bg-deep: #060E18;
      --text-light: #E0F0FF;
      --text-body: #B0C4DE;
      --text-muted: #6B7B8D;
      --border-subtle: rgba(0,212,255,0.08);
      --glass-bg: rgba(30,58,95,0.25);
      --glass-border: rgba(0,212,255,0.15);
      --radius-card: 24px;
      --radius-btn: 12px;
      --radius-tag: 40px;
      --shadow-lg: 0 8px 32px rgba(0,0,0,0.4), inset 0 1px 0 rgba(255,255,255,0.05);
      --transition-smooth: 0.3s cubic-bezier(0.25, 0.46, 0.45, 0.94);
      --max-width: 1280px;
      --space-section: clamp(4rem, 8vw, 8rem);
    }
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    html {
      scroll-behavior: smooth;
      font-family: 'Inter', 'SF Pro', 'Noto Sans SC', '思源黑体', system-ui, -apple-system, sans-serif;
      background-color: var(--bg-deep);
      color: var(--text-body);
      line-height: 1.7;
      font-weight: 400;
    }
    body {
      min-height: 100vh;
      display: flex;
      flex-direction: column;
      background: radial-gradient(ellipse at 80% 0%, #0A1A2F 0%, #060E18 60%);
    }
    img {
      max-width: 100%;
      height: auto;
      display: block;
    }
    a {
      text-decoration: none;
      color: inherit;
    }
    button, input, textarea {
      font-family: inherit;
      font-size: inherit;
      border: none;
      outline: none;
    }
    .container {
      max-width: var(--max-width);
      margin: 0 auto;
      padding: 0 clamp(1rem, 5vw, 3rem);
      width: 100%;
    }
    /* 导航 */
    #header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 72px;
      background: rgba(6,14,24,0.7);
      backdrop-filter: blur(30px);
      -webkit-backdrop-filter: blur(30px);
      border-bottom: 1px solid var(--border-subtle);
      z-index: 1000;
      display: flex;
      align-items: center;
    }
    .nav-container {
      display: flex;
      align-items: center;
      justify-content: space-between;
      height: 100%;
    }
    .logo {
      font-size: 1.5rem;
      font-weight: 700;
      color: var(--accent);
      letter-spacing: 0.5px;
      display: flex;
      align-items: center;
      gap: 0.5rem;
    }
    .logo-icon {
      width: 28px;
      height: 28px;
      background: linear-gradient(135deg, var(--accent) 0%, #0A1A2F 100%);
      border-radius: 8px;
      box-shadow: 0 0 15px rgba(0,212,255,0.5);
    }
    .nav-links {
      display: flex;
      gap: 2rem;
      list-style: none;
    }
    .nav-links a {
      color: var(--text-body);
      font-weight: 400;
      transition: color 0.2s ease;
      position: relative;
      padding: 0.25rem 0;
    }
    .nav-links a:hover {
      color: var(--text-light);
    }
    .nav-links a.active {
      color: var(--accent);
    }
    .nav-links a.active::after {
      content: '';
      position: absolute;
      bottom: -6px;
      left: 50%;
      transform: translateX(-50%);
      width: 16px;
      height: 2px;
      background: var(--accent);
      border-radius: 4px;
    }
    .hamburger {
      display: none;
      flex-direction: column;
      gap: 6px;
      cursor: pointer;
      background: transparent;
      border: none;
      padding: 8px;
    }
    .hamburger span {
      width: 24px;
      height: 2px;
      background: var(--accent);
      transition: var(--transition-smooth);
      border-radius: 4px;
    }
    /* 移动端导航 */
    @media (max-width: 768px) {
      .nav-links {
        position: fixed;
        top: 72px;
        left: 0;
        width: 100%;
        height: calc(100vh - 72px);
        background: rgba(6,14,24,0.95);
        backdrop-filter: blur(40px);
        -webkit-backdrop-filter: blur(40px);
        flex-direction: column;
        align-items: center;
        justify-content: center;
        gap: 2.5rem;
        display: none;
        z-index: 999;
      }
      .nav-links.active-mobile {
        display: flex;
      }
      .hamburger {
        display: flex;
      }
    }
    /* Hero */
    #hero {
      min-height: 90vh;
      display: flex;
      align-items: center;
      padding-top: 72px;
      position: relative;
    }
    .hero-grid {
      display: flex;
      align-items: center;
      gap: 3rem;
      flex-wrap: wrap;
    }
    .hero-text {
      flex: 1 1 50%;
    }
    .hero-visual {
      flex: 1 1 40%;
      display: flex;
      justify-content: center;
      position: relative;
    }
    .hero h1 {
      font-size: clamp(2.5rem, 5vw, 4rem);
      font-weight: 700;
      letter-spacing: -0.02em;
      color: var(--text-light);
      line-height: 1.2;
      margin-bottom: 1.5rem;
    }
    .hero-sub {
      font-size: 1.125rem;
      color: #8A9BB0;
      max-width: 480px;
      margin-bottom: 2rem;
    }
    .btn-group {
      display: flex;
      gap: 1rem;
      flex-wrap: wrap;
    }
    .btn-primary {
      background: var(--accent);
      color: var(--primary);
      font-weight: 600;
      border-radius: var(--radius-btn);
      padding: 0.75rem 2rem;
      box-shadow: 0 0 20px rgba(0,212,255,0.4);
      transition: all var(--transition-smooth);
      cursor: pointer;
      display: inline-block;
      text-align: center;
    }
    .btn-primary:hover {
      box-shadow: 0 0 35px var(--accent-glow);
      background: #33e0ff;
    }
    .btn-outline {
      background: transparent;
      border: 1px solid var(--accent);
      color: var(--accent);
      border-radius: var(--radius-btn);
      padding: 0.75rem 2rem;
      font-weight: 500;
      transition: all var(--transition-smooth);
      cursor: pointer;
      display: inline-block;
      text-align: center;
    }
    .btn-outline:hover {
      background: rgba(0,212,255,0.1);
    }
    .glass-shape {
      width: 280px;
      height: 280px;
      background: var(--glass-bg);
      backdrop-filter: blur(20px);
      -webkit-backdrop-filter: blur(20px);
      border: 1px solid var(--glass-border);
      border-radius: 48px;
      box-shadow: 0 0 60px rgba(0,212,255,0.15);
      transform: rotate(5deg);
      display: flex;
      align-items: center;
      justify-content: center;
    }
    .glass-shape-inner {
      width: 180px;
      height: 180px;
      background: rgba(0,212,255,0.05);
      border-radius: 32px;
      border: 1px solid rgba(255,255,255,0.1);
    }
    @media (max-width: 768px) {
      .hero-grid {
        flex-direction: column;
        text-align: center;
      }
      .hero-text {
        flex: 1 1 auto;
      }
      .hero-visual {
        flex: 1 1 auto;
        margin-top: 2rem;
      }
    }
    /* 通用板块标题 */
    .section-title {
      font-size: 2rem;
      font-weight: 600;
      color: var(--text-light);
      margin-bottom: 2.5rem;
      display: flex;
      align-items: center;
      gap: 1rem;
    }
    .section-title::after {
      content: '';
      flex: 1;
      height: 2px;
      background: linear-gradient(to right, var(--accent), transparent);
      max-width: 80px;
    }
    /* 优势卡片 */
    .advantages-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: clamp(1.5rem, 3vw, 2.5rem);
    }
    .glass-card {
      background: var(--glass-bg);
      backdrop-filter: blur(20px);
      -webkit-backdrop-filter: blur(20px);
      border: 1px solid var(--glass-border);
      border-radius: var(--radius-card);
      padding: clamp(1.5rem, 3vw, 2.5rem);
      box-shadow: var(--shadow-lg);
      transition: all var(--transition-smooth);
    }
    .glass-card:hover {
      border-color: rgba(0,212,255,0.5);
      box-shadow: 0 12px 40px rgba(0,0,0,0.6);
      transform: scale(1.02);
    }
    .advantage-icon {
      font-size: 2rem;
      color: var(--accent);
      margin-bottom: 1rem;
    }
    .advantage-title {
      font-size: 1.25rem;
      font-weight: 600;
      color: var(--text-light);
      margin-bottom: 0.75rem;
    }
    /* 产品服务 */
    .product-grid {
      display: grid;
      grid-template-columns: repeat(2, 1fr);
      gap: 2rem;
    }
    .product-card {
      background: var(--glass-bg);
      backdrop-filter: blur(16px);
      -webkit-backdrop-filter: blur(16px);
      border: 1px solid var(--glass-border);
      border-radius: var(--radius-card);
      padding: 2rem;
      display: flex;
      flex-direction: column;
      gap: 1rem;
    }
    .product-name {
      font-size: 1.5rem;
      font-weight: 600;
      color: var(--text-light);
    }
    .tag-list {
      display: flex;
      flex-wrap: wrap;
      gap: 0.5rem;
    }
    .tag {
      background: rgba(0,212,255,0.1);
      color: var(--accent);
      padding: 0.25rem 1rem;
      border-radius: var(--radius-tag);
      font-size: 0.75rem;
      font-weight: 500;
    }
    @media (max-width: 768px) {
      .advantages-grid, .product-grid {
        grid-template-columns: 1fr;
      }
    }
    /* 场景卡片 */
    .scenarios-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 2rem;
    }
    .scenario-card {
      background: var(--glass-bg);
      backdrop-filter: blur(12px);
      border-radius: var(--radius-card);
      overflow: hidden;
      border: 1px solid var(--glass-border);
    }
    .scenario-img {
      height: 180px;
      background-size: cover;
      background-position: center;
      position: relative;
    }
    .scenario-img::after {
      content: '';
      position: absolute;
      top:0; left:0; right:0; bottom:0;
      background: linear-gradient(to top, rgba(6,14,24,0.7), transparent);
    }
    .scenario-content {
      padding: 1.5rem;
    }
    @media (max-width: 1024px) {
      .scenarios-grid {
        grid-template-columns: repeat(2, 1fr);
      }
    }
    @media (max-width: 600px) {
      .scenarios-grid {
        grid-template-columns: 1fr;
      }
    }
    /* 案例 */
    .cases-row {
      display: grid;
      grid-template-columns: repeat(2, 1fr);
      gap: 2rem;
    }
    .case-item {
      display: flex;
      align-items: center;
      gap: 1.5rem;
      background: var(--glass-bg);
      backdrop-filter: blur(16px);
      border-radius: var(--radius-card);
      padding: 1.5rem;
      border: 1px solid var(--glass-border);
    }
    .case-avatar {
      width: 72px;
      height: 72px;
      border-radius: 20px;
      background-size: cover;
      background-position: center;
      flex-shrink: 0;
    }
    .case-meta h4 {
      color: var(--text-light);
      font-weight: 600;
    }
    .case-stat {
      font-size: 2rem;
      font-weight: 700;
      color: var(--accent);
    }
    @media (max-width: 768px) {
      .cases-row {
        grid-template-columns: 1fr;
      }
    }
    /* FAQ */
    .faq-item {
      border-bottom: 1px solid rgba(0,212,255,0.1);
      padding: 1.25rem 0;
    }
    .faq-question {
      display: flex;
      justify-content: space-between;
      align-items: center;
      cursor: pointer;
      color: var(--text-light);
      font-weight: 500;
    }
    .faq-icon {
      font-size: 1.5rem;
      transition: transform 0.2s;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease;
      color: #8A9BB0;
    }
    .faq-item.active .faq-answer {
      max-height: 200px;
      padding-top: 0.75rem;
    }
    .faq-item.active .faq-icon {
      transform: rotate(45deg);
    }
    /* CTA 表单 */
    .contact-block {
      background: rgba(10,26,47,0.8);
      backdrop-filter: blur(24px);
      border-radius: var(--radius-card);
      padding: 3rem;
      border: 1px solid var(--glass-border);
    }
    .form-input {
      width: 100%;
      padding: 0.9rem 1.25rem;
      background: rgba(255,255,255,0.05);
      border: 1px solid rgba(0,212,255,0.2);
      border-radius: var(--radius-btn);
      color: white;
      margin-bottom: 1rem;
      transition: 0.2s;
    }
    .form-input:focus {
      border-color: var(--accent);
      box-shadow: 0 0 10px rgba(0,212,255,0.2);
    }
    /* 页脚 */
    #footer {
      border-top: 1px solid var(--border-subtle);
      padding: 2rem 0;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr;
      gap: 2rem;
    }
    .copyright {
      color: var(--text-muted);
      font-size: 0.8rem;
    }
    @media (max-width: 768px) {
      .footer-grid {
        grid-template-columns: 1fr;
      }
    }
    section {
      padding: var(--space-section) 0;
    }