 0.08s ease, box-shadow 0.2s ease;
    }
    .btn:hover { transform: translateY(-1px); }
    .btn:active { transform: translateY(1px); }
    .btn.primary { background: linear-gradient(135deg, #c8d4ff, #ffe1ef); color: #283a54; }
    .footer {
      position: fixed; right: 16px; bottom: 16px; z-index: 10;
      background: var(--panel);
      padding: 10px 12px; border-radius: 16px; backdrop-filter: blur(8px);
      box-shadow: 0 8px 24px rgba(85,120,160,0.18), 0 2px 8px rgba(0,0,0,0.08);
      font-size: 12