.center {
  margin: 0;
  position: absolute;
  top: 50%;
  left: 50%;
  -ms-transform: translate(-50%, -50%);
  transform: translate(-50%, -50%);
}


/* body { background:#333; } */
.loader { 
  width:500px; 
  margin:0 auto;
  border-radius:10px;
  border:4px solid transparent;
  position:relative;
  padding:1px;
}
.loader:before {
  content:'';
  border:1px solid #FF4500; 
  border-radius:10px;
  position:absolute;
  top:-4px; 
  right:-4px; 
  bottom:-4px; 
  left:-4px;
}
.loader .loaderBar { 
  position:absolute;
  border-radius:10px;
  top:0;
  right:100%;
  bottom:0;
  left:0;
  background:#FF4500; 
  width:0;
  animation:borealisBar 2s linear infinite;
}

@keyframes borealisBar {
  0% {
    left:0%;
    right:100%;
    width:0%;
  }
  10% {
    left:0%;
    right:75%;
    width:25%;
  }
  90% {
    right:0%;
    left:75%;
    width:25%;
  }
  100% {
    left:100%;
    right:0%;
    width:0%;
  }
}