@keyframes spinner {
    to {transform: rotate(360deg);}
  }
   
  .spinner:before {
    content: '';
    box-sizing: border-box;
    position: absolute;
    top: 50%;
    left: 50%;
    width: 40px;
    height: 40px;
    margin-top: -15px;
    margin-left: -15px;
    border-radius: 50%;
    border: 4px solid transparent;
    border-top-color: #3d3be6;
    animation: spinner 1s linear infinite;
    z-index: 999;
  }