preload.css

#overlay {
    width: 100%;
    height: 100%;
    position: fixed;
    top: 0;
    left: 0;
    background:rgba(34, 38, 42, 0.54);
    display:none;
    justify-content: center;
    align-items: center;
    z-index:9999;
  }
  
  .load {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    /*change these sizes to fit into your project*/
    width: 70px;
    height: 70px;
  }
  .load hr {
    border: 0;
    margin: 0;
    width: 40%;
    height: 40%;
    position: absolute;
    border-radius: 50%;
    animation: spin 2s ease infinite;
  }
  
  .load :first-child {
    background: #333;
    animation-delay: -1.5s;
  }
  .load :nth-child(2) {
    background: #333;
    animation-delay: -1s;
  }
  .load :nth-child(3) {
    background: #333;
    animation-delay: -0.5s;
  }
  .load :last-child {
    background: #333;
  }
  
  @keyframes spin {
    0%,
    100% {
      transform: translate(0);
    }
    25% {
      transform: translate(160%);
    }
    50% {
      transform: translate(160%, 160%);
    }
    75% {
      transform: translate(0, 160%);
    }
  }