bs749.less

// ...............

@grid-columns:      3;
@grid-gutter-width: 33px;

// ...............

.grid-column-template { // Ok, the cons: this creates a dummy class in the output
    position: relative;
    // Prevent columns from collapsing when empty
    min-height: 1px;
    // Inner gutter via padding
    padding-left:  (@grid-gutter-width / 2);
    padding-right: (@grid-gutter-width / 2);
}

.make-grid-columns() {
    .col(); // kickstart it
    .col(@index: @grid-columns) when (@index > 0) {
        .col((@index - 1));
        .col-xs-@{index}, 
        .col-sm-@{index},
        .col-md-@{index},
        .col-lg-@{index} {
            &:extend(.grid-column-template);
        }
    }
}

// ...............

.make-grid-columns();