/* roulang page: index */
:root {
      --bg-dark: #060B18;
      --bg-navy: #0B1528;
      --card-bg: rgba(13, 27, 62, 0.72);
      --primary-blue: #0066FF;
      --primary-cyan: #00D2FF;
      --text-white: #FFFFFF;
      --text-muted: #B8C6E2;
      --border-line: rgba(0, 210, 255, 0.2);
    }

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

    body {
      background-color: var(--bg-dark);
      color: var(--text-muted);
      font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
      line-height: 1.6;
      overflow-x: hidden;
    }

    /* 玻璃拟态卡片与边框发光 */
    .glass-card {
      background: var(--card-bg);
      backdrop-filter: blur(14px);
      -webkit-backdrop-filter: blur(14px);
      border: 1px solid var(--border-line);
      box-shadow: 0 8px 32px 0 rgba(0, 0, 0, 0.37), 0 0 15px rgba(0, 210, 255, 0.08);
      border-radius: 14px;
      transition: all 0.3s cubic-bezier(0.16, 1, 0.3, 1);
    }

    .glass-card:hover {
      border-color: rgba(0, 210, 255, 0.5);
      box-shadow: 0 12px 40px 0 rgba(0, 0, 0, 0.45), 0 0 24px rgba(0, 210, 255, 0.25);
      transform: translateY(-3px);
    }

    /* 科技发光按钮 */
    .btn-glow-primary {
      background: linear-gradient(135deg, #0066FF 0%, #00D2FF 100%);
      color: #FFFFFF;
      box-shadow: 0 0 22px rgba(0, 102, 255, 0.55);
      font-weight: 600;
      border-radius: 8px;
      transition: all 0.25s ease;
      display: inline-flex;
      align-items: center;
      justify-content: center;
    }

    .btn-glow-primary:hover {
      box-shadow: 0 0 32px rgba(0, 210, 255, 0.75);
      transform: translateY(-2px);
      color: #FFFFFF;
    }

    .btn-glow-outline {
      background: rgba(13, 27, 62, 0.5);
      border: 1px solid var(--primary-cyan);
      color: var(--primary-cyan);
      backdrop-filter: blur(8px);
      border-radius: 8px;
      font-weight: 600;
      transition: all 0.25s ease;
      display: inline-flex;
      align-items: center;
      justify-content: center;
    }

    .btn-glow-outline:hover {
      background: rgba(0, 210, 255, 0.15);
      box-shadow: 0 0 20px rgba(0, 210, 255, 0.3);
      color: #FFFFFF;
      transform: translateY(-2px);
    }

    /* 斜切与网格修饰 */
    .hero-clip {
      position: relative;
      background-size: cover;
      background-position: center;
    }

    .hero-clip::after {
      content: '';
      position: absolute;
      bottom: 0;
      left: 0;
      right: 0;
      height: 70px;
      background: linear-gradient(to bottom right, transparent 49.5%, var(--bg-dark) 50%);
    }

    .band-alternate {
      background: linear-gradient(180deg, rgba(11, 21, 40, 0.95) 0%, rgba(6, 11, 24, 0.98) 100%);
      border-top: 1px solid rgba(0, 210, 255, 0.1);
      border-bottom: 1px solid rgba(0, 210, 255, 0.1);
    }

    /* 表单控件定制 */
    .form-control-tech {
      width: 100%;
      background: rgba(6, 11, 24, 0.85);
      border: 1px solid rgba(0, 210, 255, 0.25);
      border-radius: 8px;
      padding: 12px 16px;
      color: #FFFFFF;
      outline: none;
      transition: border-color 0.2s, box-shadow 0.2s;
    }

    .form-control-tech:focus {
      border-color: #00D2FF;
      box-shadow: 0 0 12px rgba(0, 210, 255, 0.35);
    }

    /* FAQ 手风琴展开动效 */
    .faq-content {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s cubic-bezier(0, 1, 0, 1);
    }
    .faq-item.active .faq-content {
      max-height: 280px;
      transition: max-height 0.3s ease-in-out;
    }
    .faq-item.active .faq-icon {
      transform: rotate(180deg);
      color: #00D2FF;
    }