/* roulang page: index */
/* 全局设计变量与重置 */
    :root {
      --deep-blue: #0A192F;
      --dark-bg: #0B203A;
      --cyan: #00E5FF;
      --coral: #FF6B6B;
      --card-bg: rgba(30, 42, 58, 0.6);
      --border-light: rgba(0, 229, 255, 0.15);
      --text-soft: #B0C4DE;
      --text-white: #FFFFFF;
      --shadow-glow: 0 8px 32px rgba(0, 229, 255, 0.08);
      --radius-lg: 16px;
      --radius-btn: 30px;
      --transition: all 0.3s ease;
      --font-sans: 'Inter', 'PingFang SC', 'Microsoft YaHei', 'Helvetica Neue', sans-serif;
    }

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

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

    body {
      font-family: var(--font-sans);
      background: radial-gradient(circle at 20% 10%, #0B203A 0%, #0A192F 90%);
      color: var(--text-white);
      line-height: 1.6;
      min-height: 100vh;
      position: relative;
      overflow-x: hidden;
    }

    /* 背景纹理：声波纹/网格线 */
    body::before {
      content: "";
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 100%;
      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;
      pointer-events: none;
      z-index: 0;
    }

    .container {
      max-width: 1280px;
      margin: 0 auto;
      padding: 0 24px;
      position: relative;
      z-index: 1;
    }

    /* 导航栏 */
    .header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      background: rgba(10, 25, 47, 0.85);
      backdrop-filter: blur(20px);
      -webkit-backdrop-filter: blur(20px);
      border-bottom: 1px solid var(--cyan);
      z-index: 100;
      padding: 16px 0;
      transition: var(--transition);
    }

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

    .logo {
      display: flex;
      align-items: center;
      gap: 8px;
      font-size: 1.8rem;
      font-weight: 800;
      background: linear-gradient(135deg, var(--cyan) 0%, #4DF0FF 100%);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
      letter-spacing: 1px;
      text-decoration: none;
    }

    .logo-icon {
      font-size: 2rem;
      filter: drop-shadow(0 0 6px var(--cyan));
    }

    .nav-links {
      display: flex;
      align-items: center;
      gap: 32px;
    }

    .nav-links a {
      color: var(--text-white);
      text-decoration: none;
      font-weight: 500;
      font-size: 1rem;
      position: relative;
      padding: 4px 0;
      transition: color 0.2s;
    }

    .nav-links a::after {
      content: "";
      position: absolute;
      bottom: -4px;
      left: 0;
      width: 0%;
      height: 2px;
      background: var(--cyan);
      transition: width 0.3s ease;
      box-shadow: 0 0 8px var(--cyan);
    }

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

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

    .nav-links a.active {
      color: var(--cyan);
      text-shadow: 0 0 8px rgba(0,229,255,0.6);
    }

    .btn-primary {
      background: var(--cyan);
      color: #0A192F;
      border: none;
      padding: 12px 28px;
      border-radius: var(--radius-btn);
      font-weight: 700;
      font-size: 1rem;
      cursor: pointer;
      transition: var(--transition);
      box-shadow: 0 0 20px rgba(0, 229, 255, 0.5);
      text-decoration: none;
      display: inline-block;
      letter-spacing: 0.5px;
    }

    .btn-primary:hover {
      background: #4DF0FF;
      box-shadow: 0 0 30px rgba(0, 229, 255, 0.8);
      transform: translateY(-2px);
    }

    .btn-outline {
      background: transparent;
      border: 2px solid var(--cyan);
      color: var(--cyan);
      padding: 10px 28px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      transition: var(--transition);
      text-decoration: none;
      display: inline-flex;
      align-items: center;
      gap: 8px;
    }

    .btn-outline:hover {
      background: rgba(0, 229, 255, 0.15);
      box-shadow: 0 0 20px rgba(0,229,255,0.3);
    }

    .hamburger {
      display: none;
      flex-direction: column;
      gap: 6px;
      background: transparent;
      border: none;
      cursor: pointer;
    }

    .hamburger span {
      width: 28px;
      height: 3px;
      background: var(--cyan);
      border-radius: 4px;
      transition: var(--transition);
    }

    /* 移动端菜单 */
    .mobile-menu {
      display: none;
      position: fixed;
      top: 80px;
      left: 0;
      width: 100%;
      background: rgba(10, 25, 47, 0.95);
      backdrop-filter: blur(25px);
      padding: 24px;
      flex-direction: column;
      gap: 24px;
      z-index: 99;
      border-bottom: 1px solid var(--cyan);
    }

    .mobile-menu a {
      color: white;
      font-size: 1.2rem;
      text-decoration: none;
      font-weight: 500;
    }

    /* Hero */
    .hero {
      padding: 160px 0 100px;
      display: flex;
      align-items: center;
      gap: 60px;
    }

    .hero-left {
      flex: 1;
    }

    .hero-left h1 {
      font-size: 3rem;
      font-weight: 800;
      line-height: 1.2;
      margin-bottom: 24px;
    }

    .hero-left .highlight {
      color: var(--cyan);
      text-shadow: 0 0 12px var(--cyan);
    }

    .hero-sub {
      font-size: 1.2rem;
      color: var(--text-soft);
      margin-bottom: 36px;
    }

    .hero-buttons {
      display: flex;
      gap: 20px;
      flex-wrap: wrap;
    }

    .hero-right {
      flex: 1;
      background: url('/assets/images/backpic/back-1.webp') center/cover no-repeat;
      border-radius: 24px;
      height: 400px;
      position: relative;
      overflow: hidden;
      box-shadow: 0 20px 40px rgba(0,0,0,0.5);
      border: 1px solid rgba(0,229,255,0.2);
    }

    .glass-overlay {
      position: absolute;
      bottom: 20px;
      left: 20px;
      background: rgba(10, 25, 47, 0.7);
      backdrop-filter: blur(12px);
      padding: 16px 24px;
      border-radius: 16px;
      border: 1px solid var(--border-light);
      color: var(--cyan);
      font-weight: 600;
    }

    /* 板块通用 */
    section {
      padding: 100px 0;
    }

    .section-title {
      font-size: 2.4rem;
      font-weight: 700;
      margin-bottom: 16px;
      position: relative;
      display: inline-block;
    }

    .section-title::after {
      content: "";
      display: block;
      width: 60px;
      height: 4px;
      background: var(--cyan);
      margin-top: 12px;
      box-shadow: 0 0 15px var(--cyan);
    }

    /* 亮点网格 */
    .highlights-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr;
      gap: 24px;
      margin-top: 40px;
    }

    .highlight-card {
      background: var(--card-bg);
      backdrop-filter: blur(12px);
      border: 1px solid var(--border-light);
      border-radius: var(--radius-lg);
      padding: 32px;
      transition: var(--transition);
    }

    .highlight-card:hover {
      transform: translateY(-6px);
      box-shadow: 0 12px 30px rgba(0,229,255,0.2);
      border-color: var(--cyan);
    }

    .big-card {
      grid-row: span 2;
      display: flex;
      flex-direction: column;
      justify-content: center;
    }

    .data-number {
      font-size: 3rem;
      font-weight: 800;
      color: var(--coral);
    }

    /* 服务瀑布流 */
    .services-flow {
      display: flex;
      flex-direction: column;
      gap: 40px;
      margin-top: 40px;
    }

    .service-row {
      display: flex;
      align-items: center;
      gap: 40px;
    }

    .service-row.reverse {
      flex-direction: row-reverse;
    }

    .service-img {
      flex: 1;
      border-radius: 20px;
      overflow: hidden;
      border: 1px solid rgba(0,229,255,0.3);
    }

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

    .service-text {
      flex: 1;
    }

    /* 解决方案对比 */
    .compare-table {
      display: flex;
      gap: 24px;
      margin-top: 40px;
    }

    .compare-col {
      flex: 1;
      background: var(--card-bg);
      backdrop-filter: blur(12px);
      border-radius: var(--radius-lg);
      padding: 32px;
      border: 1px solid var(--border-light);
    }

    .compare-col.recommended {
      border-color: var(--coral);
      position: relative;
    }

    .badge {
      background: var(--coral);
      color: white;
      padding: 4px 12px;
      border-radius: 20px;
      font-size: 0.8rem;
      font-weight: 700;
      position: absolute;
      top: -12px;
      right: 20px;
    }

    /* 案例横向滚动 */
    .cases-scroll {
      display: flex;
      gap: 24px;
      overflow-x: auto;
      padding: 20px 0;
      scrollbar-width: thin;
      margin-top: 30px;
    }

    .case-card {
      min-width: 280px;
      background: var(--card-bg);
      backdrop-filter: blur(12px);
      border-radius: var(--radius-lg);
      padding: 24px;
      border: 1px solid var(--border-light);
    }

    /* FAQ */
    .faq-item {
      background: var(--card-bg);
      backdrop-filter: blur(12px);
      border-radius: 16px;
      margin-bottom: 16px;
      border: 1px solid var(--border-light);
    }

    .faq-question {
      padding: 20px;
      font-weight: 600;
      cursor: pointer;
      display: flex;
      justify-content: space-between;
    }

    .faq-answer {
      padding: 0 20px 20px;
      color: var(--text-soft);
      display: none;
    }

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

    /* 联系 */
    .contact-grid {
      display: flex;
      gap: 40px;
      margin-top: 40px;
    }

    input, textarea {
      width: 100%;
      background: rgba(255,255,255,0.05);
      border: 1px solid var(--border-light);
      border-radius: 12px;
      padding: 14px;
      color: white;
      margin-bottom: 16px;
      transition: 0.2s;
    }

    input:focus, textarea:focus {
      outline: none;
      border-color: var(--cyan);
      box-shadow: 0 0 12px rgba(0,229,255,0.4);
    }

    footer {
      background: #0A192F;
      padding: 40px 0;
      border-top: 1px solid var(--cyan);
    }

    @media (max-width: 1024px) {
      .hero {
        flex-direction: column;
      }
      .highlights-grid {
        grid-template-columns: 1fr 1fr;
      }
      .service-row, .service-row.reverse {
        flex-direction: column;
      }
      .compare-table {
        flex-direction: column;
      }
    }

    @media (max-width: 768px) {
      .nav-links { display: none; }
      .hamburger { display: flex; }
      .hero-left h1 { font-size: 2.2rem; }
      .highlights-grid { grid-template-columns: 1fr; }
      .contact-grid { flex-direction: column; }
    }