amis2/scss/utilities/flex/_flex.scss

@mixin make-flex($prefix: '.') {
  #{$prefix}flex-1 {
    flex: 1 1 0%;
  }

  #{$prefix}flex-auto {
    flex: 1 1 auto;
  }

  #{$prefix}flex-initial {
    flex: 0 1 auto;
  }
  #{$prefix}flex-none {
    flex: none;
  }
}

@include make-flex();
@each $deivce in map-keys($devices) {
  @include media-device($deivce) {
    @include make-flex('.' + selector-escape($deivce + ':'));
  }
}