Nested Rules example LESS

gistfile1.css

@lightblue:#a9c6d2;

.cloudstyle(){
   content: '';
   position: absolute;
   background: @lightblue;
   z-index: -1
} //every Cloud has this style

#cloud {
   width: 350px;
   height: 120px;
   position: relative;
   margin: 120px auto 20px;
   background: @lightblue;    
   .rounded(100px);
   &:before {
.cloudstyle(); //we add here this class
      width: 180px;
      height: 180px;
      top: -90px;
      right: 50px;
      .rounded(200px);
  }
  &:after {
      .cloudstyle();//and here
     width: 100px;
      height: 100px;
      top: -50px;
      left: 50px;   
      .rounded(100px);
  }
}