Bootstrap's missing 480px columns mixins

bootstrap-ms-column-mixins.less

/*
	An extension of andyl's hack – https://gist.github.com/andyl/6360906
	in a mixin version.
*/

@import 'bootstrap'; // if you haven't already

@screen-ms-min: 480px;

.make-ms-column(@columns; @gutter: @grid-gutter-width) {
  position: relative;
  min-height: 1px;
  padding-left:  (@gutter / 2);
  padding-right: (@gutter / 2);

  @media (min-width: @screen-ms-min) {
    float: left;
    width: percentage((@columns / @grid-columns));
  }
}
.make-ms-column-offset(@columns) {
  @media (min-width: @screen-ms-min) {
    margin-left: percentage((@columns / @grid-columns));
  }
}
.make-ms-column-push(@columns) {
  @media (min-width: @screen-ms-min) {
    left: percentage((@columns / @grid-columns));
  }
}
.make-ms-column-pull(@columns) {
  @media (min-width: @screen-ms-min) {
    right: percentage((@columns / @grid-columns));
  }
}