/* roulang page: index */
/* ----- 设计变量与基础重置 ----- */
    :root {
      --primary: #0A0E27;
      --accent: #00F0FF;
      --bg-deep: #050814;
      --glass-bg: rgba(255, 255, 255, 0.03);
      --glass-border: rgba(0, 240, 255, 0.15);
      --glow-shadow: 0 0 20px rgba(0, 240, 255, 0.5);
      --text-main: #FFFFFF;
      --text-muted: #B0C7D9;
      --radius-lg: 20px;
      --radius-pill: 50px;
      --transition: 0.3s ease;
      --font-brand: "Inter", "Roboto", "PingFang SC", "Microsoft YaHei", sans-serif;
    }

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

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

    body {
      background-color: var(--bg-deep);
      font-family: var(--font-brand);
      color: var(--text-main);
      line-height: 1.6;
      -webkit-font-smoothing: antialiased;
      overflow-x: hidden;
    }

    h1, h2, h3, h4 {
      font-weight: 700;
    }

    h1 {
      font-size: clamp(2.8rem, 8vw, 3.8rem);
      font-weight: 900;
      letter-spacing: -0.5px;
      line-height: 1.2;
    }

    h2 {
      font-size: clamp(2rem, 6vw, 2.5rem);
    }

    h3 {
      font-size: 1.5rem;
      font-weight: 600;
    }

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

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

    .container {
      max-width: 1280px;
      margin: 0 auto;
      padding: 0 24px;
      width: 100%;
    }

    /* 玻璃拟态卡片 */
    .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-lg);
      box-shadow: 0 8px 32px rgba(0, 0, 0, 0.4);
    }

    /* 按钮系统 */
    .btn {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      padding: 14px 32px;
      border-radius: var(--radius-pill);
      font-weight: 700;
      letter-spacing: 0.5px;
      transition: all var(--transition);
      cursor: pointer;
      border: none;
      font-size: 1rem;
    }

    .btn-primary {
      background: linear-gradient(135deg, #00F0FF 0%, #0088CC 100%);
      color: white;
      box-shadow: var(--glow-shadow);
    }

    .btn-primary:hover {
      box-shadow: 0 0 32px rgba(0, 240, 255, 0.8);
      transform: translateY(-2px);
    }

    .btn-outline {
      background: transparent;
      border: 1.5px solid var(--accent);
      color: var(--accent);
      backdrop-filter: blur(8px);
    }

    .btn-outline:hover {
      background: rgba(0, 240, 255, 0.1);
      transform: translateY(-2px);
    }

    /* 板块标题装饰 */
    .section-badge {
      color: var(--accent);
      font-weight: 600;
      text-transform: uppercase;
      letter-spacing: 2px;
      font-size: 0.9rem;
      margin-bottom: 1rem;
      display: inline-block;
    }

    /* 粒子装饰轻量处理 (不会泛滥) */
    .accent-line {
      width: 60px;
      height: 3px;
      background: var(--accent);
      box-shadow: 0 0 12px rgba(0, 240, 255, 0.6);
      margin: 1rem 0;
    }

    /* 主题背景图片应用 */
    .hero-section {
      background-image: url('/assets/images/backpic/back-1.webp');
      background-size: cover;
      background-position: center;
      background-blend-mode: overlay;
      position: relative;
      min-height: 100vh;
      display: flex;
      align-items: center;
    }

    .hero-section::after {
      content: "";
      position: absolute;
      top: 0; left: 0; right: 0; bottom: 0;
      background: radial-gradient(circle at 30% 40%, rgba(0,240,255,0.03) 0%, rgba(5,8,20,0.92) 80%);
    }

    /* 导航 */
    .navbar {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 1000;
      background: rgba(5, 8, 20, 0.75);
      backdrop-filter: blur(30px);
      -webkit-backdrop-filter: blur(30px);
      border-bottom: 1px solid rgba(0, 240, 255, 0.2);
      transition: var(--transition);
    }

    .nav-container {
      display: flex;
      align-items: center;
      justify-content: space-between;
      padding: 16px 24px;
      max-width: 1280px;
      margin: 0 auto;
    }

    .logo {
      font-size: 1.8rem;
      font-weight: 800;
      color: white;
      letter-spacing: -0.5px;
      background: linear-gradient(to right, #fff, #ddd);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
    }

    .nav-menu {
      display: flex;
      gap: 2.5rem;
      list-style: none;
      font-weight: 600;
      font-size: Im0.95rem;
    }

    .nav-menu a {
      color: var(--text-muted);
      position: relative;
      padding: 5px 0;
    }

    .nav-menu a:hover,
    .nav-menu a.active {
      color: var(--accent);
    }

    .hamburger {
      display: none;
      background: none;
      border: none;
      color: white;
      font-size: 1.6rem;
      cursor: pointer;
    }

    @media (max-width: 768px) {
      .nav-menu {
        position: fixed;
        top: 0;
        right: -100%;
        width: 70%;
        height: 100vh;
        background: rgba(5, 8, 20, 0.98);
        backdrop-filter: blur(40px);
        flex-direction: column;
        justify-content: center;
        align-items: center;
        gap: 2.5rem;
        transition: 0.35s ease-in-out;
      }
      .nav-menu.active {
        right: 0;
      }
      .hamburger {
        display: block;
        z-index: 1001;
      }
    }

    /* Hero 内部对齐 */
    .hero-content {
      position: relative;
      z-index: 2;
      text-align: center;
    }

    section {
      padding: 80px 0;
    }

    .scroll-arrow {
      position: absolute;
      bottom: 30px;
      left: 50%;
      transform: translateX(-50%);
      color: var(--accent);
      font-size: 2rem;
      animation: bounce 2s infinite;
    }

    @keyframes bounce {
      0%, 100% { transform: translateY(0); }
      50% { transform: translateY(12px); }
    }

    /* 特色网格交错布局 */
    .feature-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 30px;
      margin-top: 40px;
    }

    .feature-item {
      padding: 30px 20px;
      text-align: center;
    }

    .feature-icon {
      font-size: 2.4rem;
      color: var(--accent);
      margin-bottom: 20px;
    }

    /* 产品图文交错 */
    .product-row {
      display: flex;
      align-items: center;
      gap: 60px;
      margin-bottom: 70px;
      flex-wrap: wrap;
    }
    .product-row.reverse {
      flex-direction: row-reverse;
    }
    .product-img {
      flex: 1 1 45%;
      border-radius: var(--radius-lg);
      overflow: hidden;
      border: 1px solid var(--glass-border);
    }
    .product-text {
      flex: 1 1 45%;
    }

    /* 场景卡片 */
    .scene-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 32px;
      margin-top: 40px;
    }

    .scene-card {
      padding: 0 0 24px 0;
      overflow: hidden;
    }
    .scene-card img {
      width: 100%;
      height: 220px;
      object-fit: cover;
    }
    .scene-info {
      padding: 24px;
    }

    /* 案例数据 */
    .stats-grid {
      display: grid;
      grid-template-columns: repeat(2, 1fr);
      gap: 35px;
    }
    .stat-number {
      font-size: 3rem;
      font-weight: 900;
      color: var(--accent);
      line-height: 1.2;
    }

    /* FAQ 手风琴 */
    .faq-item {
      border-bottom: 1px solid rgba(255,255,255,0.08);
      margin-bottom: 14px;
    }
    .faq-question {
      display: flex;
      justify-content: space-between;
      align-items: center;
      padding: 24px 5px;
      font-weight: 600;
      cursor: pointer;
      font-size: 1.15rem;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.4s ease, padding 0.4s;
      color: var(--text-muted);
      padding: 0 5px;
    }
    .faq-item.active .faq-answer {
      max-height: 200px;
      padding-bottom: 16px;
    }

    /* CTA Banner */
    .cta-banner {
      background: linear-gradient(104deg, #0A0E27 30%, rgba(0,134,200,0.12));
      border: 1px solid rgba(0,240,255,0.2);
      border-radius: 28px;
      padding: 70px 40px;
      text-align: center;
    }

    footer {
      background: rgba(5,8,20,0.9);
      padding: 60px 0 30px;
      margin-top: 20px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 30px;
    }

    @media (max-width: 1024px) {
      .feature-grid, .scene-grid { grid-template-columns: repeat(2, 1fr); }
    }
    @media (max-width: 768px) {
      .feature-grid, .scene-grid, .footer-grid, .stats-grid { grid-template-columns: 1fr; }
      .product-row { flex-direction: column; }
    }