.container {
  width: 600px;
  height:600px;
  position:relative;
  margin: 0 auto;
  //border: 1px solid;
  overflow: hidden;
     @include background(radial-gradient( #28a9dd, #0d4e77));   
  
  &:after {
    content: "";
    display: block;
    position: absolute;
    width:850px;
    height:850px;
    top:-125px;
    left: -125px;
   @include background(image-url("http://static.puzzlexperts.com/images/RadialBurst_bkgd.png") no-repeat top center,
                      radial-gradient( #28a9dd, #0d4e77)
                      );   
    background-position: center;
    background-blend-mode: screen;
    @include animation(spin 20s linear infinite); 
    
  }
  
}


@include keyframes(spin){
   0% {@include rotateZ(0deg)} 100% {@include rotateZ(300deg)}
}