.div-back-loader{
    position: fixed;
    justify-content: center;
    display: none;
    align-items: center;
    width: 100%;
    height: 100%;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    background: rgba(0, 0, 0, .5);
    z-index: 999;
}
.loader {
  width: 64px;
  aspect-ratio: 1;
  background: 
    radial-gradient(farthest-side at bottom right,#b5011a 90%,#0000),
    radial-gradient(farthest-side at bottom left ,#b5011a 90%,#0000),
    radial-gradient(farthest-side at top    right,#b5011a 90%,#0000),
    radial-gradient(farthest-side at top    left ,#b5011a 90%,#0000),
    radial-gradient(farthest-side at bottom right,white 90%,#0000),
    radial-gradient(farthest-side at bottom left ,white 90%,#0000),
    radial-gradient(farthest-side at top    right,white 90%,#0000),
    radial-gradient(farthest-side at top    left ,white 90%,#0000),
    radial-gradient(farthest-side at bottom right,#18502b 90%,#0000),
    radial-gradient(farthest-side at bottom left ,#18502b 90%,#0000),
    radial-gradient(farthest-side at top    right,#18502b 90%,#0000),
    radial-gradient(farthest-side at top    left ,#18502b 90%,#0000);

    
  background-size: 25% 25%;
  background-repeat: no-repeat;
  animation: l16 2s infinite;
}
@keyframes l16{
  0% {background-position: 
        calc(1*100%/3) calc(1*100%/3), calc(2*100%/3) calc(1*100%/3), calc(1*100%/3) calc(2*100%/3), calc(2*100%/3) calc(2*100%/3),
        calc(1*100%/3) calc(1*100%/3), calc(2*100%/3) calc(1*100%/3), calc(1*100%/3) calc(2*100%/3), calc(2*100%/3) calc(2*100%/3),
        calc(1*100%/3) calc(1*100%/3), calc(2*100%/3) calc(1*100%/3), calc(1*100%/3) calc(2*100%/3), calc(2*100%/3) calc(2*100%/3)}
  16.67% {background-position: 
        calc(0*100%/3) calc(0*100%/3), calc(3*100%/3) calc(0*100%/3), calc(0*100%/3) calc(3*100%/3), calc(3*100%/3) calc(3*100%/3),
        calc(1*100%/3) calc(1*100%/3), calc(2*100%/3) calc(1*100%/3), calc(1*100%/3) calc(2*100%/3), calc(2*100%/3) calc(2*100%/3),
        calc(1*100%/3) calc(1*100%/3), calc(2*100%/3) calc(1*100%/3), calc(1*100%/3) calc(2*100%/3), calc(2*100%/3) calc(2*100%/3)}
  33.33% {background-position: 
        calc(0*100%/3) calc(0*100%/3), calc(3*100%/3) calc(0*100%/3), calc(0*100%/3) calc(3*100%/3), calc(3*100%/3) calc(3*100%/3),
        calc(0*100%/3) calc(0*100%/3), calc(3*100%/3) calc(0*100%/3), calc(0*100%/3) calc(3*100%/3), calc(3*100%/3) calc(3*100%/3),
        calc(1*100%/3) calc(1*100%/3), calc(2*100%/3) calc(1*100%/3), calc(1*100%/3) calc(2*100%/3), calc(2*100%/3) calc(2*100%/3)}
  50% {background-position: 
        calc(0*100%/3) calc(0*100%/3), calc(3*100%/3) calc(0*100%/3), calc(0*100%/3) calc(3*100%/3), calc(3*100%/3) calc(3*100%/3),
        calc(0*100%/3) calc(0*100%/3), calc(3*100%/3) calc(0*100%/3), calc(0*100%/3) calc(3*100%/3), calc(3*100%/3) calc(3*100%/3),
        calc(0*100%/3) calc(0*100%/3), calc(3*100%/3) calc(0*100%/3), calc(0*100%/3) calc(3*100%/3), calc(3*100%/3) calc(3*100%/3)}
  66.67% {background-position: 
        calc(1*100%/3) calc(1*100%/3), calc(2*100%/3) calc(1*100%/3), calc(1*100%/3) calc(2*100%/3), calc(2*100%/3) calc(2*100%/3),
        calc(0*100%/3) calc(0*100%/3), calc(3*100%/3) calc(0*100%/3), calc(0*100%/3) calc(3*100%/3), calc(3*100%/3) calc(3*100%/3),
        calc(0*100%/3) calc(0*100%/3), calc(3*100%/3) calc(0*100%/3), calc(0*100%/3) calc(3*100%/3), calc(3*100%/3) calc(3*100%/3)}
  83.33% {background-position: 
        calc(1*100%/3) calc(1*100%/3), calc(2*100%/3) calc(1*100%/3), calc(1*100%/3) calc(2*100%/3), calc(2*100%/3) calc(2*100%/3),
        calc(1*100%/3) calc(1*100%/3), calc(2*100%/3) calc(1*100%/3), calc(1*100%/3) calc(2*100%/3), calc(2*100%/3) calc(2*100%/3),
        calc(0*100%/3) calc(0*100%/3), calc(3*100%/3) calc(0*100%/3), calc(0*100%/3) calc(3*100%/3), calc(3*100%/3) calc(3*100%/3)}
  100% {background-position: 
        calc(1*100%/3) calc(1*100%/3), calc(2*100%/3) calc(1*100%/3), calc(1*100%/3) calc(2*100%/3), calc(2*100%/3) calc(2*100%/3),
        calc(1*100%/3) calc(1*100%/3), calc(2*100%/3) calc(1*100%/3), calc(1*100%/3) calc(2*100%/3), calc(2*100%/3) calc(2*100%/3),
        calc(1*100%/3) calc(1*100%/3), calc(2*100%/3) calc(1*100%/3), calc(1*100%/3) calc(2*100%/3), calc(2*100%/3) calc(2*100%/3)}
}