/* roulang page: index */
:root {
      --deep-blue: #0A0F1E;
      --cyan: #00E5FF;
      --purple: #A855F7;
      --card-bg: rgba(255, 255, 255, 0.03);
      --glass-border: rgba(0, 229, 255, 0.15);
      --text-primary: #FFFFFF;
      --text-secondary: #B0C4DE;
      --text-muted: #6B7A8F;
      --shadow-glow: 0 0 24px rgba(0, 229, 255, 0.6);
      --radius-card: 20px;
      --radius-btn: 50px;
      --font-mono: 'Inter', 'SF Mono', 'Fira Code', monospace;
    }

    * {
      box-sizing: border-box;
    }

    body {
      margin: 0;
      font-family: 'PingFang SC', 'Microsoft YaHei', 'Helvetica Neue', sans-serif;
      background-color: var(--deep-blue);
      color: var(--text-primary);
      line-height: 1.7;
      -webkit-font-smoothing: antialiased;
      scroll-behavior: smooth;
    }

    .glass-card {
      background: var(--card-bg);
      backdrop-filter: blur(16px);
      -webkit-backdrop-filter: blur(16px);
      border: 1px solid var(--glass-border);
      border-radius: var(--radius-card);
      box-shadow: 0 8px 32px rgba(0, 0, 0, 0.5);
      transition: all 0.3s ease;
    }

    .glass-card:hover {
      border-color: var(--cyan);
      box-shadow: 0 0 20px rgba(0, 229, 255, 0.25);
      transform: translateY(-4px);
    }

    .glow-btn {
      background: linear-gradient(135deg, var(--cyan), var(--purple));
      color: #0A0F1E;
      font-weight: 600;
      border: none;
      border-radius: var(--radius-btn);
      padding: 0.85rem 2.2rem;
      box-shadow: 0 4px 14px rgba(0, 229, 255, 0.4);
      transition: all 0.25s ease;
      display: inline-flex;
      align-items: center;
      justify-content: center;
      letter-spacing: 0.5px;
      cursor: pointer;
    }

    .glow-btn:hover {
      box-shadow: var(--shadow-glow);
      transform: scale(1.03);
      filter: brightness(1.1);
    }

    .ghost-btn {
      background: transparent;
      border: 1px solid var(--cyan);
      color: var(--cyan);
      border-radius: var(--radius-btn);
      padding: 0.85rem 2.2rem;
      font-weight: 500;
      transition: all 0.25s ease;
      display: inline-flex;
      align-items: center;
      justify-content: center;
      cursor: pointer;
      backdrop-filter: blur(8px);
    }

    .ghost-btn:hover {
      background: rgba(0, 229, 255, 0.12);
      border-color: #fff;
      color: #fff;
      box-shadow: 0 0 18px rgba(0, 229, 255, 0.5);
    }

    .nav-blur {
      background: rgba(10, 15, 30, 0.75);
      backdrop-filter: blur(20px);
      -webkit-backdrop-filter: blur(20px);
      border-bottom: 1px solid rgba(0, 229, 255, 0.25);
    }

    .section-padding {
      padding-top: 5rem;
      padding-bottom: 5rem;
    }

    .container-custom {
      max-width: 1280px;
      margin: 0 auto;
      padding-left: 1.5rem;
      padding-right: 1.5rem;
    }

    .text-glow {
      text-shadow: 0 0 12px rgba(0, 229, 255, 0.7);
    }

    .border-glow {
      border: 1px solid rgba(0, 229, 255, 0.4);
    }

    .hero-bg {
      background: radial-gradient(circle at 30% 40%, rgba(0, 229, 255, 0.12) 0%, transparent 45%),
                  radial-gradient(circle at 80% 60%, rgba(168, 85, 247, 0.15) 0%, transparent 50%);
    }

    .grid-line {
      background-image: linear-gradient(rgba(0, 229, 255, 0.08) 1px, transparent 1px),
                      linear-gradient(90deg, rgba(0, 229, 255, 0.08) 1px, transparent 1px);
      background-size: 40px 40px;
    }

    /* 数值等宽风格 */
    .metric-number {
      font-family: var(--font-mono);
      font-weight: 600;
      color: var(--cyan);
    }

    /* 手风琴动画 */
    .faq-content {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.35s ease, padding 0.3s ease;
    }
    .faq-item.active .faq-content {
      max-height: 200px;
      padding-top: 1rem;
      padding-bottom: 1rem;
    }
    .faq-item.active .faq-icon {
      transform: rotate(45deg);
      color: var(--cyan);
    }
    .faq-icon {
      transition: transform 0.3s ease, color 0.2s;
    }

    /* 输入框发光 */
    input:focus, select:focus, textarea:focus {
      outline: none;
      border-color: var(--cyan) !important;
      box-shadow: 0 0 12px rgba(0, 229, 255, 0.5);
    }

    @media (max-width: 768px) {
      .section-padding {
        padding-top: 3.5rem;
        padding-bottom: 3.5rem;
      }
      .glass-card {
        border-radius: 14px;
      }
    }