#disp-checking-auth {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background-color: rgba(255, 255, 255, 0.8);
  z-index: 9999;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
}
#disp-checking-auth .spinner {
  border: 4px solid #f3f3f3;
  border-top: 4px solid #3498db;
  border-radius: 50%;
  width: 30px;
  height: 30px;
  animation: spin 1s linear infinite;
  margin-bottom: 10px;
}
@keyframes spin {
  0% { transform: rotate(0deg); }
  100% { transform: rotate(360deg); }
}
#disp-checking-auth .msgbox {
  font-size: 1.2rem;
  font-weight: bold;
}