a precess production

precess-input-1413605028.scss

@mixin box-sizing( $value ){
  -webkit-box-sizing:$value;
  -moz-box-sizing:$value;
  box-sizing:$value;
}
 
.shape{
  @include box-sizing('border-box');
  border:1px solid red;
  height:100px;
  width:100px;
}

.square{
  @extend .shape;
  color:red;
}

.circle{
  @extend .shape;
  border-radius:100%;
}

precess-output-1413605028.css

.shape, .square, .circle {
  -webkit-box-sizing: "border-box";
  -moz-box-sizing: "border-box";
  box-sizing: "border-box";
  border: 1px solid red;
  height: 100px;
  width: 100px;
}

.square {
  color: red;
}

.circle {
  border-radius: 100%;
}