/* roulang page: index */
:root {
      --bg-deep: #0B0E1E;
      --cyan: #00F0FF;
      --orange: #FF5E3A;
      --card-bg: rgba(18, 24, 45, 0.65);
      --border-glow: rgba(0, 240, 255, 0.15);
      --text-body: #B0C4DE;
      --text-muted: #6B7B9A;
      --shadow-card: 0 4px 24px rgba(0,0,0,0.4);
      --shadow-glow: 0 8px 40px rgba(0, 240, 255, 0.25);
      --radius-lg: 16px;
      --radius-btn: 12px;
    }

    * {
      box-sizing: border-box;
    }

    body {
      margin: 0;
      font-family: "PingFang SC", "Microsoft YaHei", "Helvetica Neue", "Inter", "Roboto", sans-serif;
      background-color: var(--bg-deep);
      color: var(--text-body);
      line-height: 1.5;
      -webkit-font-smoothing: antialiased;
    }

    /* 背景网格与光晕 */
    body::before {
      content: "";
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 100%;
      background-image: 
        linear-gradient(rgba(0, 240, 255, 0.03) 1px, transparent 1px),
        linear-gradient(90deg, rgba(0, 240, 255, 0.03) 1px, transparent 1px);
      background-size: 60px 60px;
      pointer-events: none;
      z-index: -1;
    }

    .hero-glow {
      position: absolute;
      top: 20%;
      right: 10%;
      width: 500px;
      height: 500px;
      background: radial-gradient(circle, rgba(0,240,255,0.15) 0%, rgba(255,94,58,0.08) 50%, transparent 70%);
      filter: blur(120px);
      pointer-events: none;
      z-index: 0;
    }

    /* 玻璃拟态卡片 */
    .glass-card {
      background: var(--card-bg);
      backdrop-filter: blur(16px);
      -webkit-backdrop-filter: blur(16px);
      border-radius: var(--radius-lg);
      border: 1px solid var(--border-glow);
      box-shadow: var(--shadow-card);
      transition: transform 0.3s ease, box-shadow 0.3s ease, border-color 0.3s;
    }

    .glass-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-glow);
      border-color: rgba(0, 240, 255, 0.4);
    }

    /* 主按钮 */
    .btn-primary {
      background: var(--cyan);
      color: #0B0E1E;
      font-weight: 600;
      border-radius: var(--radius-btn);
      padding: 0.75rem 2rem;
      border: none;
      cursor: pointer;
      transition: all 0.3s ease;
      display: inline-flex;
      align-items: center;
      justify-content: center;
      text-decoration: none;
      letter-spacing: 0.5px;
    }

    .btn-primary:hover {
      box-shadow: 0 0 24px rgba(0,240,255,0.6);
      transform: scale(1.02);
      background: #33F5FF;
    }

    .btn-ghost {
      background: transparent;
      border: 1.5px solid var(--cyan);
      color: var(--cyan);
      font-weight: 500;
      border-radius: var(--radius-btn);
      padding: 0.75rem 2rem;
      cursor: pointer;
      transition: all 0.3s ease;
      text-decoration: none;
      display: inline-flex;
      align-items: center;
      justify-content: center;
    }

    .btn-ghost:hover {
      background: rgba(0, 240, 255, 0.1);
      box-shadow: 0 0 16px rgba(0,240,255,0.3);
    }

    .btn-cta {
      background: var(--orange);
      color: white;
      font-weight: 700;
      border-radius: var(--radius-btn);
      padding: 1rem 2.5rem;
      border: none;
      cursor: pointer;
      transition: all 0.3s ease;
      text-decoration: none;
      display: inline-flex;
      align-items: center;
      justify-content: center;
      font-size: 1.25rem;
    }

    .btn-cta:hover {
      filter: brightness(1.15);
      transform: scale(1.03);
      box-shadow: 0 0 32px rgba(255,94,58,0.5);
    }

    /* 导航激活态 */
    .nav-link {
      color: #B0C4DE;
      text-decoration: none;
      position: relative;
      padding-bottom: 4px;
      transition: color 0.2s;
    }

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

    .nav-link.active {
      color: var(--cyan);
    }

    .nav-link.active::after {
      content: "";
      position: absolute;
      bottom: -6px;
      left: 0;
      width: 100%;
      height: 2px;
      background: var(--cyan);
      border-radius: 2px;
    }

    /* 手风琴 */
    .faq-item {
      border-bottom: 1px solid rgba(0, 240, 255, 0.1);
    }

    .faq-question {
      display: flex;
      align-items: center;
      cursor: pointer;
      padding: 1.2rem 0;
      transition: color 0.2s;
    }

    .faq-question h3 {
      font-weight: 600;
      color: white;
      margin-left: 12px;
    }

    .faq-indicator {
      width: 3px;
      height: 24px;
      background: #6B7B9A;
      border-radius: 2px;
      transition: background 0.3s, box-shadow 0.3s;
    }

    .faq-item.active .faq-indicator {
      background: var(--cyan);
      box-shadow: 0 0 12px var(--cyan);
    }

    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.4s ease;
      padding-left: 1.5rem;
    }

    .faq-item.active .faq-answer {
      max-height: 300px;
      padding-bottom: 1.2rem;
    }

    /* 移动端菜单 */
    .mobile-menu {
      background: rgba(11, 14, 30, 0.9);
      backdrop-filter: blur(20px);
      -webkit-backdrop-filter: blur(20px);
    }

    @media (max-width: 768px) {
      h1 {
        font-size: 2.5rem !important;
      }
      h2 {
        font-size: 1.8rem !important;
      }
    }