._dash-loading {
    margin: auto;
    color: transparent;
    width: 0;
    height: 0;
    text-align: center;
  }
  
  ._dash-loading::after {
    content: '';
    display: inline-block;
    width: 2rem;
    height: 2rem;
    color: black;
    vertical-align: text-bottom;
    border: 0.25em solid currentColor;
    border-right-color: transparent;
    border-radius: 50%;
    -webkit-animation: spinner-border 0.75s linear infinite;
    animation: spinner-border 0.75s linear infinite;
    margin-top: 2rem;
  }