/* roulang page: index */
/* ----- 设计变量与基础重置 ----- */
    :root {
      --bg-deep: #0B0E1A;
      --bg-card: rgba(18, 24, 43, 0.6);
      --primary-cyan: #00E5FF;
      --primary-cyan-hover: #33EAFF;
      --accent-purple: #7B2FF7;
      --text-white: #F0F4FF;
      --text-secondary: #8892B0;
      --border-glow: rgba(0, 229, 255, 0.15);
      --shadow-glow: 0 0 20px rgba(0, 229, 255, 0.1);
      --radius-xl: 32px;
      --radius-lg: 24px;
      --radius-md: 16px;
      --radius-sm: 12px;
      --radius-pill: 50px;
      --font-mono: 'SF Mono', 'Inter', 'PingFang SC', 'Microsoft YaHei', monospace;
      --font-sans: 'PingFang SC', 'Microsoft YaHei', 'Helvetica Neue', sans-serif;
      --transition-smooth: 0.3s cubic-bezier(0.25, 0.8, 0.25, 1.2);
      --container-max: 1280px;
      --gap-grid: 24px;
      --backdrop-blur: blur(24px);
    }

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

    html {
      scroll-behavior: smooth;
      font-size: 16px;
    }

    body {
      background-color: var(--bg-deep);
      color: var(--text-secondary);
      font-family: var(--font-sans);
      line-height: 1.6;
      -webkit-font-smoothing: antialiased;
      overflow-x: hidden;
      background-image: 
        linear-gradient(rgba(0, 229, 255, 0.02) 1px, transparent 1px),
        linear-gradient(90deg, rgba(0, 229, 255, 0.02) 1px, transparent 1px);
      background-size: 40px 40px;
    }

    .container {
      max-width: var(--container-max);
      margin: 0 auto;
      padding: 0 32px;
    }

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

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

    button, .btn {
      cursor: pointer;
      font-family: inherit;
      border: none;
      background: none;
      transition: var(--transition-smooth);
      display: inline-flex;
      align-items: center;
      justify-content: center;
      gap: 8px;
      font-weight: 600;
      letter-spacing: 0.03em;
    }

    /* 自定义滚动条 */
    ::-webkit-scrollbar {
      width: 6px;
    }
    ::-webkit-scrollbar-track {
      background: var(--bg-deep);
    }
    ::-webkit-scrollbar-thumb {
      background: var(--primary-cyan);
      border-radius: 10px;
    }

    /* ----- 悬浮胶囊导航 ----- */
    .nav-capsule {
      position: fixed;
      top: 24px;
      left: 50%;
      transform: translateX(-50%);
      width: auto;
      max-width: 90vw;
      z-index: 1000;
      background: rgba(12, 16, 28, 0.75);
      backdrop-filter: var(--backdrop-blur);
      border-radius: var(--radius-pill);
      padding: 10px 28px;
      border: 1px solid rgba(0, 229, 255, 0.25);
      box-shadow: 0 8px 32px rgba(0, 0, 0, 0.5);
      display: flex;
      align-items: center;
      justify-content: space-between;
      transition: background 0.3s, border-color 0.3s;
    }

    .nav-capsule.scrolled {
      background: rgba(8, 12, 24, 0.9);
      border-color: var(--primary-cyan);
      box-shadow: 0 0 28px rgba(0, 229, 255, 0.2);
    }

    .logo-area {
      display: flex;
      align-items: center;
      gap: 10px;
      color: var(--text-white);
      font-weight: 700;
      font-size: 1.3rem;
      letter-spacing: -0.5px;
    }

    .logo-icon {
      width: 32px;
      height: 32px;
      background: conic-gradient(from 90deg at 50% 50%, var(--primary-cyan), var(--accent-purple), var(--primary-cyan));
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      color: #0B0E1A;
      font-weight: 800;
      font-size: 1.2rem;
      box-shadow: 0 0 15px var(--primary-cyan);
    }

    .nav-links {
      display: flex;
      gap: 28px;
      align-items: center;
      list-style: none;
    }

    .nav-links a {
      color: var(--text-secondary);
      font-weight: 500;
      font-size: 0.95rem;
      padding: 6px 2px;
      position: relative;
    }

    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: 0;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--primary-cyan);
      transition: width 0.3s;
      box-shadow: 0 0 10px var(--primary-cyan);
    }

    .nav-links a:hover, .nav-links a.active {
      color: var(--primary-cyan);
    }

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

    .mobile-menu-toggle {
      display: none;
      background: rgba(0,229,255,0.1);
      border-radius: 50%;
      width: 44px;
      height: 44px;
      align-items: center;
      justify-content: center;
      color: var(--primary-cyan);
      font-size: 1.5rem;
    }

    /* ----- Hero 首屏 ----- */
    .hero {
      min-height: 100vh;
      display: flex;
      align-items: center;
      position: relative;
      overflow: hidden;
      padding: 120px 0 80px;
    }

    #particle-canvas {
      position: absolute;
      top: 0;
      left: 0;
      width: 100%;
      height: 100%;
      z-index: 0;
      pointer-events: none;
    }

    .hero .container {
      position: relative;
      z-index: 2;
      display: flex;
      align-items: center;
      justify-content: space-between;
      gap: 48px;
      flex-wrap: wrap;
    }

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

    .hero h1 {
      font-size: clamp(3.2rem, 8vw, 5rem);
      font-weight: 700;
      line-height: 1.1;
      color: var(--text-white);
      margin-bottom: 24px;
      letter-spacing: -0.02em;
      text-shadow: 0 0 30px rgba(0,229,255,0.3);
    }

    .hero-sub {
      font-size: 1.25rem;
      color: var(--text-secondary);
      max-width: 600px;
      margin-bottom: 40px;
      line-height: 1.7;
    }

    .btn-group {
      display: flex;
      gap: 20px;
      flex-wrap: wrap;
    }

    .btn-primary {
      background: var(--primary-cyan);
      color: #0B0E1A;
      padding: 14px 36px;
      border-radius: 30px;
      font-weight: 700;
      box-shadow: 0 4px 20px rgba(0,229,255,0.5);
    }
    .btn-primary:hover {
      background: var(--primary-cyan-hover);
      box-shadow: 0 6px 30px rgba(0,229,255,0.8);
      transform: translateY(-2px);
    }

    .btn-secondary {
      background: transparent;
      border: 1px solid var(--primary-cyan);
      color: var(--primary-cyan);
      padding: 14px 36px;
      border-radius: 30px;
    }
    .btn-secondary:hover {
      background: rgba(0,229,255,0.1);
      border-color: var(--primary-cyan-hover);
      color: white;
    }

    .hero-visual {
      flex: 1 1 450px;
      position: relative;
      display: flex;
      justify-content: center;
    }

    .glass-card-preview {
      background: var(--bg-card);
      backdrop-filter: var(--backdrop-blur);
      border: 1px solid var(--border-glow);
      border-radius: var(--radius-xl);
      padding: 20px;
      box-shadow: var(--shadow-glow);
      width: 100%;
      max-width: 480px;
      background-image: url('/assets/images/backpic/back-1.webp');
      background-size: cover;
      background-position: center;
      background-blend-mode: overlay;
      aspect-ratio: 16 / 10;
      display: flex;
      align-items: flex-end;
      justify-content: flex-start;
      position: relative;
    }

    .glass-card-preview::before {
      content: "实时视讯信号";
      position: absolute;
      bottom: 20px;
      left: 20px;
      background: rgba(0,0,0,0.6);
      backdrop-filter: blur(10px);
      padding: 8px 18px;
      border-radius: 40px;
      color: var(--primary-cyan);
      font-weight: 500;
      border: 1px solid var(--primary-cyan);
    }

    /* 通用区块 */
    section {
      padding: 100px 0;
      position: relative;
    }

    .section-title {
      text-align: center;
      margin-bottom: 60px;
    }
    .section-title h2 {
      font-size: clamp(2rem, 5vw, 2.8rem);
      font-weight: 600;
      color: var(--primary-cyan);
      margin-bottom: 12px;
    }
    .title-decor {
      width: 60px;
      height: 4px;
      background: linear-gradient(90deg, var(--accent-purple), var(--primary-cyan));
      margin: 0 auto;
      border-radius: 4px;
    }

    /* 优势卡片 */
    .features-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: var(--gap-grid);
    }
    .feature-card {
      background: var(--bg-card);
      backdrop-filter: var(--backdrop-blur);
      border: 1px solid var(--border-glow);
      border-radius: var(--radius-md);
      padding: 32px 24px;
      transition: all 0.3s ease;
    }
    .feature-card:hover {
      transform: translateY(-6px);
      border-color: var(--primary-cyan);
      box-shadow: 0 12px 40px rgba(0,229,255,0.2);
    }
    .feature-icon {
      font-size: 2.2rem;
      color: var(--primary-cyan);
      margin-bottom: 20px;
      filter: drop-shadow(0 0 8px var(--primary-cyan));
    }
    .feature-card h3 {
      color: white;
      font-size: 1.4rem;
      margin-bottom: 10px;
    }

    /* 解决方案交替卡片 */
    .solution-row {
      display: flex;
      gap: 32px;
      margin-bottom: 48px;
      align-items: center;
      flex-wrap: wrap;
    }
    .solution-img {
      flex: 1 1 45%;
      border-radius: var(--radius-lg);
      overflow: hidden;
      background: rgba(0,229,255,0.05);
      border: 1px solid rgba(123,47,247,0.3);
    }
    .solution-img img {
      width: 100%;
      height: auto;
      object-fit: cover;
      aspect-ratio: 4/3;
      mix-blend-mode: lighten;
    }
    .solution-text {
      flex: 1 1 45%;
    }
    .solution-text h3 {
      color: white;
      font-size: 1.8rem;
      margin-bottom: 16px;
    }
    .text-link {
      color: var(--primary-cyan);
      display: inline-flex;
      align-items: center;
      gap: 6px;
      font-weight: 600;
    }

    /* 数据卡片 */
    .stats-grid {
      display: flex;
      justify-content: center;
      gap: 40px;
      flex-wrap: wrap;
      margin-bottom: 60px;
    }
    .stat-item {
      text-align: center;
    }
    .stat-number {
      font-family: var(--font-mono);
      font-size: 3rem;
      font-weight: 700;
      color: var(--primary-cyan);
    }
    .case-cards {
      display: grid;
      grid-template-columns: repeat(3,1fr);
      gap: 24px;
    }
    .case-card {
      background: var(--bg-card);
      backdrop-filter: blur(20px);
      border: 1px solid rgba(123,47,247,0.25);
      border-radius: var(--radius-md);
      padding: 24px;
    }

    /* FAQ */
    .faq-item {
      background: rgba(18,24,43,0.5);
      border: 1px solid rgba(0,229,255,0.1);
      border-radius: var(--radius-sm);
      margin-bottom: 16px;
      overflow: hidden;
    }
    .faq-question {
      padding: 20px 24px;
      display: flex;
      justify-content: space-between;
      align-items: center;
      font-weight: 600;
      color: white;
      cursor: pointer;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.4s ease;
      background: rgba(0,229,255,0.02);
      padding: 0 24px;
    }
    .faq-item.active .faq-answer {
      max-height: 200px;
      padding: 20px 24px;
      border-left: 3px solid var(--primary-cyan);
    }

    /* 联系 */
    .contact-glow {
      background: radial-gradient(circle at center, rgba(123,47,247,0.2) 0%, transparent 70%);
    }

    footer {
      border-top: 1px solid rgba(0,229,255,0.3);
      padding: 40px 0;
    }

    @media (max-width: 992px) {
      .features-grid { grid-template-columns: repeat(2,1fr); }
      .case-cards { grid-template-columns: 1fr; }
      .nav-links { gap: 16px; }
    }
    @media (max-width: 768px) {
      .nav-capsule { top: 12px; padding: 8px 20px; }
      .nav-links { display: none; }
      .mobile-menu-toggle { display: flex; }
      .hero .container { flex-direction: column; }
    }