mempool/frontend/src/app/components/blockchain/blockchain.component.html

<div class="text-center" class="blockchain-wrapper">
  <div class="position-container">

    <span [hidden]="isLoading">
      <app-mempool-blocks></app-mempool-blocks>
      <app-blockchain-blocks></app-blockchain-blocks>
      <div id="divider"></div>
    </span>

    <ng-template [ngIf]="isLoading">
      <div class="loading-block">
        <h3>Waiting for blocks...</h3>
        <br>
        <div class="spinner-border text-light"></div>
      </div>
    </ng-template>

  </div>
</div>