@mixin test() {
  $values: blue red;
@each $val   in $values {
  color  : $val;
  @for $i   from  2   through    10 {
   background: $i;
  }
}
@for $i from   2 through 10 {
  color: $i;
}
 @while $k   >   0 {
  color: $k;
}

}