/* loading animation */
.loader {
    margin: 10px auto;
    border: 5px solid #dadada;
    border-radius: 50%;
    border-top: 5px solid #023361;
    width: 50px;
    height: 50px;
    animation: spinner 1s linear infinite;
  }

  @keyframes spinner {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
  }
  /* end */