.spinner{
    border:5px solid rgba(0, 0, 0, .2);
    width: 40px;
    height: 40px;
    border-radius: 50%;
    border-left-color: darkred;

    -webkit-animation : spin 0.8s linear infinite;
     -o-animation: spin 0.8s linear infinite;
     animation: spin 0.8s linear infinite;

    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    margin: auto;
  }

  @keyframes spin {
    from{transform: rotate(0deg); }
     to {transform: rotate(360deg); }
}