/* roulang page: index */
:root {
      --primary-deep: #0A1628;
      --primary-bg: #0E1A2B;
      --accent-cyan: #00E5FF;
      --accent-orange: #FF6B35;
      --glass-bg: rgba(255,255,255,0.04);
      --glass-border: rgba(0,229,255,0.2);
      --glass-border-hover: rgba(0,229,255,0.45);
      --text-primary: #E8EDF2;
      --text-secondary: #8899AA;
      --text-muted: #556677;
      --shadow-glow: 0 0 20px rgba(0,229,255,0.2);
      --shadow-card: 0 10px 28px rgba(0,0,0,0.5);
      --radius-lg: 18px;
      --radius-md: 12px;
      --radius-sm: 8px;
      --font-sans: 'Inter', 'PingFang SC', 'Microsoft YaHei', 'Hiragino Sans GB', sans-serif;
    }

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

    body {
      font-family: var(--font-sans);
      background-color: var(--primary-deep);
      color: var(--text-primary);
      line-height: 1.6;
      -webkit-font-smoothing: antialiased;
    }

    .container {
      max-width: 1200px;
      margin: 0 auto;
      padding: 0 24px;
    }

    /* 玻璃拟态卡片 */
    .glass-card {
      background: rgba(255,255,255,0.03);
      backdrop-filter: blur(14px);
      -webkit-backdrop-filter: blur(14px);
      border: 1px solid rgba(0,229,255,0.18);
      border-radius: var(--radius-lg);
      box-shadow: 0 10px 30px rgba(0,0,0,0.4);
      transition: all 0.3s ease;
    }
    .glass-card:hover {
      transform: translateY(-5px);
      border-color: var(--glass-border-hover);
      box-shadow: 0 16px 40px rgba(0,0,0,0.55), 0 0 24px rgba(0,229,255,0.15);
    }

    /* 按钮 */
    .btn-primary {
      background: linear-gradient(135deg, #00E5FF, #0088CC);
      color: #FFFFFF;
      font-weight: 600;
      border: none;
      border-radius: var(--radius-sm);
      padding: 12px 28px;
      box-shadow: 0 0 20px rgba(0,229,255,0.35);
      transition: all 0.3s ease;
      text-decoration: none;
      display: inline-block;
      cursor: pointer;
    }
    .btn-primary:hover {
      filter: brightness(1.18);
      box-shadow: 0 0 32px rgba(0,229,255,0.55);
      color: #fff;
      text-decoration: none;
    }

    .btn-secondary {
      background: transparent;
      border: 1px solid rgba(0,229,255,0.55);
      color: #00E5FF;
      font-weight: 500;
      border-radius: var(--radius-sm);
      padding: 12px 28px;
      transition: all 0.3s ease;
      text-decoration: none;
      display: inline-block;
    }
    .btn-secondary:hover {
      background: rgba(0,229,255,0.08);
      border-color: #00E5FF;
      color: #00E5FF;
      text-decoration: none;
    }

    /* 导航 */
    .custom-nav {
      background: rgba(10,22,40,0.88);
      backdrop-filter: blur(18px);
      -webkit-backdrop-filter: blur(18px);
      border-bottom: 1px solid rgba(0,229,255,0.18);
      position: fixed;
      width: 100%;
      top: 0;
      z-index: 100;
    }
    .nav-link {
      color: #8899AA;
      font-weight: 500;
      padding: 0.5rem 1rem;
      transition: 0.3s;
      position: relative;
      text-decoration: none;
    }
    .nav-link::after {
      content: '';
      position: absolute;
      bottom: -2px;
      left: 50%;
      width: 0;
      height: 2px;
      background: #00E5FF;
      box-shadow: 0 0 10px #00E5FF;
      transition: 0.3s;
      transform: translateX(-50%);
    }
    .nav-link:hover {
      color: #00E5FF;
    }
    .nav-link:hover::after {
      width: 70%;
    }
    .active-nav {
      color: #00E5FF !important;
      font-weight: 600;
    }
    .logo-text {
      font-weight: 700;
      font-size: 1.5rem;
      letter-spacing: -0.5px;
      color: #fff;
      text-decoration: none;
    }
    .logo-text span {
      color: #00E5FF;
    }

    /* hero */
    .hero-section {
      min-height: 85vh;
      display: flex;
      align-items: center;
      background: radial-gradient(circle at 30% 40%, rgba(0,229,255,0.06) 0%, transparent 60%);
      position: relative;
      overflow: hidden;
    }
    .hero-bg-img {
      position: absolute;
      right: 0;
      top: 0;
      width: 45%;
      height: 100%;
      background-image: url('/assets/images/backpic/back-1.webp');
      background-size: cover;
      background-position: left center;
      opacity: 0.2;
      mask-image: linear-gradient(to left, rgba(0,0,0,0.9) 0%, rgba(0,0,0,0.1) 90%);
      -webkit-mask-image: linear-gradient(to left, rgba(0,0,0,0.9) 0%, rgba(0,0,0,0.1) 90%);
    }

    h1 {
      font-size: clamp(2.5rem, 5vw, 3.4rem);
      font-weight: 700;
      letter-spacing: -0.02em;
      color: #FFFFFF;
      line-height: 1.2;
    }
    h2 {
      font-size: 2rem;
      font-weight: 600;
      color: #E8EDF2;
      margin-bottom: 1rem;
      display: inline-block;
      position: relative;
    }
    .section-title {
      margin-bottom: 2.5rem;
    }
    .section-title::after {
      content: '';
      display: block;
      width: 60px;
      height: 3px;
      background: linear-gradient(90deg, #00E5FF, transparent);
      margin-top: 8px;
    }

    .service-row-card {
      display: flex;
      align-items: center;
      gap: 20px;
      padding: 20px;
    }
    .icon-glow {
      font-size: 2.2rem;
      color: #00E5FF;
      filter: drop-shadow(0 0 8px #00E5FF);
    }

    .stat-number {
      font-size: 3rem;
      font-weight: 800;
      color: #00E5FF;
      text-shadow: 0 0 18px rgba(0,229,255,0.7);
      line-height: 1;
    }

    .case-img {
      width: 100%;
      height: 200px;
      object-fit: cover;
      border-radius: 12px;
      box-shadow: 0 8px 20px rgba(0,0,0,0.6);
    }

    .faq-item {
      border-bottom: 1px solid rgba(0,229,255,0.12);
    }
    .faq-question {
      padding: 18px 8px;
      font-weight: 500;
      color: #E8EDF2;
      cursor: pointer;
      display: flex;
      justify-content: space-between;
      align-items: center;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.4s ease;
      background: rgba(0,229,255,0.02);
      padding: 0 16px;
      color: #BCC8D4;
    }
    .faq-item.active .faq-answer {
      max-height: 200px;
      padding: 16px;
    }
    .arrow-icon {
      transition: transform 0.3s;
      color: #00E5FF;
    }
    .faq-item.active .arrow-icon {
      transform: rotate(180deg);
    }

    footer {
      background: #060E1A;
      border-top: 1px solid rgba(0,229,255,0.12);
    }

    @media (max-width: 768px) {
      .hero-bg-img {
        width: 100%;
        opacity: 0.15;
      }
      .service-row-card {
        flex-direction: column;
        align-items: flex-start;
      }
    }