flexgrid

_grid.scss

.row {
  display: flex;
  flex-direction: row;
  flex-wrap: nowrap;
  margin-bottom: $base-line-height/4;
}

@for $i from 1 through 12 {
  .col-#{$i} {
    flex-basis: (100% / 12 * $i);
  }
}

.col-auto {
  flex: 1;
}

[class*='col-'] {
  margin-right: 6px;
}