Tiny SCSS Flexbox Grid

flexgrid.scss

/*
 * Flexbox grid SCSS library
 * Author: Roman Hargrave
 * License: ASL 2.0
 * The smallest grid system ever designed?
 * */

@mixin flex-grid($classname: 'flexg', $columns: 16, $gutter: 0, $col-gutter: 10px) {

  $column_name-format: #{$classname}-c-;
  $offset_name-format: #{$classname}-o-;

  .#{$classname}-row {
    display:    flex;
    flex-flow:  row;
    padding: 0 $gutter;

    > *[class *= "#{$classname}-c"]:first-child {
      padding-left: 0px;
    }

    > *[class *= "#{$classname}-c"]:last-child {
      padding-right: 0px;
    }
  }

  $col-base-size: 100 / $columns;

  @for $unit from 1 to $columns + 1 {
    .#{$column_name-format}#{$unit} {
      flex-grow: 1;
      width: #{$col-base-size * $unit * 1%};
      padding: 0 $col-gutter;
    }

    .#{$offset_name-format}#{$unit} {
      left: #{$col-base-size * $unit * 1%};
    }
  }
}