@for $nCols from 1 to 12 {

@for $colWidth from 1 to $nCols {

.col-# { $colWidth } -# { $nCols } {

& , &-xs , &-sm , &-md , &-lg {

& , &-last {

@include span ( $colWidth of $nCols ) ;

}

&-last {

margin-right : 0 !important ;

}

}

&-xs {

}

&-sm {

@media ( max-width : $sm-col-breakpoint ) {

width : 100% ;

}

}

& , &-md {

@media ( max-width : $md-col-breakpoint ) {

width : 100% ;

}

}

&-lg {

@media ( max-width : $lg-col-breakpoint ) {

width : 100% ;

}

}

@for $offset from 1 to $nCols {

&-offset-$offset {

@include span ( isolate $colWidth at $offset of $nCols ) ;

}

}

}

}