sass-site/source/assets/css/layout/_grid-system.scss

.sl-l-grid {

  &,
  &--flex-columns > .sl-l-grid__column { display: flex; }

  flex-wrap: wrap;
  margin: 0;
  padding: 0;
  list-style: none;

  &__column { flex: 1; }
}

@each $breakpoint,
      $size in $sl-breakpoints {
  $prefix: if(($breakpoint == 'none'), '', '#{$breakpoint}-');

  @include sl-breakpoint-set($breakpoint,
                             $size) {

    .sl-l-#{$prefix}grid {

      &--top { align-items: flex-start; }

      &--center { align-items: center; }

      &--bottom { align-items: flex-end; }

      &--stretch { align-items: stretch; }

      &--baseline { align-items: baseline; }

      &--justify {

        &-left { justify-content: flex-start; }

        &-center { justify-content: center; }

        &-right { justify-content: flex-end; }

        &-space {

          &-between { justify-content: space-between; }

          &-around { justify-content: space-around; }

          &-evenly { justify-content: space-evenly; }
        }
      }

      &--fit > .sl-l-grid__column { flex: 1; }

      &--full > .sl-l-grid__column { flex: 0 0 100%; }

      @for $i from 2 through 12 {

        &--divide-by-#{$i} > .sl-l-grid__column { flex: 0 0 (100 / $i) * 1%; }
      }

      &__column {

        &--top { align-self: flex-start !important; }

        &--center { align-self: center !important; }

        &--bottom { align-self: flex-end !important; }

        &--baseline { align-self: baseline !important; }

        &--stretch { align-self: stretch !important; }

        &--auto-size { flex: none !important; }

        @for $i from 1 through 11 {

          &--#{$i}-of-12 { width: (100% / 12) * $i !important; }
        }

        &--full { width: 100% !important; }
      }

      &--gutters {
        margin: {
          right: -(sl-px-to-rem(16px));
          left: -(sl-px-to-rem(16px));
        };

        > .sl-l-grid__column {
          padding: {
            right: sl-px-to-rem(16px);
            left: sl-px-to-rem(16px);
          };
        }

        &-large {
          margin: {
            right: -(sl-px-to-rem(32px));
            left: -(sl-px-to-rem(32px));
          };

          > .sl-l-grid__column {
            padding: {
              right: sl-px-to-rem(32px);
              left: sl-px-to-rem(32px);
            };
          }
        }

        &-small {
          margin: {
            right: -(sl-px-to-rem(8px));
            left: -(sl-px-to-rem(8px));
          };

          > .sl-l-grid__column {
            padding: {
              right: sl-px-to-rem(8px);
              left: sl-px-to-rem(8px);
            };
          }
        }
      }
    }
  }
}