.loader {
    position: fixed;
    width: 100%;
    height: 100%;
    overflow: hidden;
    display: block;
    top: 50%;
    left: 50%;
    background: #fff;
    transform: translate(-50%, -50%);
    z-index: 99999999;
}
.loader .sk-folding-cube {
    position: absolute;
    top: calc(50% - 20px);
    left: calc(50% - 20px);
    transform: translate(-50%, -50%);
    border-radius: 50%;
    overflow: hidden;
    animation: center 3.2s ease-in-out infinite;
     border: 5px solid #f3f3f3;
      border-radius: 50%;
      border-top: 5px solid #30bbef;
      width: 50px;
      height: 50px;
      -webkit-animation: spin 2s linear infinite;
      animation: spin 2s linear infinite;
}
@-webkit-keyframes spin {
  0% { -webkit-transform: rotate(0deg); }
  100% { -webkit-transform: rotate(360deg); }
}

@keyframes spin {
  0% { transform: rotate(0deg); }
  100% { transform: rotate(360deg); }
}