<div style="display:flex; flex-direction: column; width: 100%; justify-content:center; flex: 1;">
  <div style="flex: 1; min-height: 0px"></div>
  <div style="text-align: center; flex: 9">
    <mat-spinner [strokeWidth]="10" style="display: inline-block"></mat-spinner>
    <div>Authenticating...<br>"{{redirectUrl ? redirectUrl : '/'}}"</div>
  </div>
</div>