.#{$prefix}headergroup {
    @include st-box;
    @include st-box-orient(vertical);
    flex-shrink: 0;

    // the group header is just an element with the x-gridcolumn class on it, it is not
    // an actual component, therefore we need an extra rule to turn off its border whenever
    // the group is configured with border: false
    &.#{$prefix}noborder-trbl > .#{$prefix}gridcolumn {
        border: 0 !important
    }

}
.#{$prefix}headergroup-inner {
    @include st-box-flex;
}