// Additionnal “utility” breakpoints aliases // ex. @include respond-to(“portrait-up”) {…} @function breakpoint($bp) {

@if $bp == 'mobile' {
  @return '(max-width: #{$tiny})';
}
@else if $bp == 'portrait' {
  @return '(min-width: #{$tiny + 1}) and (max-width: #{$small})';
}
@else if $bp == 'landscape' {
  @return '(min-width: #{$small + 1}) and (max-width: #{$medium})';
}
@else if $bp == 'desktop' {
  @return '(min-width: #{$medium + 1})';
}
@else if $bp == 'portrait-down' {
  @return '(max-width: #{$small})';
}
@else if $bp == 'portrait-up' {
  @return '(min-width: #{$tiny + 1})';
}
@else if $bp == 'landscape-down' {
  @return '(max-width: #{$medium})';
}
@else if $bp == 'landscape-up' {
  @return '(min-width: #{$small + 1})';
}
@else if $bp == 'retina' {
  @return '(-webkit-min-device-pixel-ratio: 2), (min-resolution: 192dpi), (min-resolution: 2dppx)';
}

}

@mixin respond-to($value) {

$string: breakpoint($value);
@media screen and #{$string} {
  @content;
}

}