.loader {
    animation:spin 1s infinite linear;
    border:solid 2vmin transparent;
    border-radius:50%;
    border-right-color:#09f;
    border-top-color:#09f;
    box-sizing:border-box;
    height:12vmin;
    left:calc(50% - 6vmin);
    position:fixed;
    top:calc(40% - 4vmin);
    width:12vmin;
    z-index:1;
    &:before {
      animation:spin 2s infinite linear;
      border:solid 2vmin transparent;
      border-radius:50%;
      border-right-color:#3cf;
      border-top-color:#3cf;
      box-sizing:border-box;
      content:"";
      height:8vmin;
      left:0;
      position:absolute;
      top:0;
      width:8vmin;
    }
    &:after {
      animation:spin 3s infinite linear;
      border:solid 2vmin transparent;
      border-radius:50%;
      border-right-color:#6ff;
      border-top-color:#6ff;
      box-sizing:border-box;
      content:"";
      height:4vmin;
      left:2vmin;
      position:absolute;
      top:2vmin;
      width:4vmin;
    }
  }
  
  @keyframes spin {
    100% {
      transform:rotate(360deg);
    }
  }