$mobile-portrait: "max-width: 320px" !default
$mobile: "max-width: 520px" !default
$tablet: "min-width: 520px" !default
$medium: "max-width: 799px" !default
$classic: "min-width: 960px" !default

@mixin breakpoint($point)
  @if $point == mobile-portrait
    @media ($mobile-portrait)
      @content

  @else if $point == mobile
    @media ($mobile)
      @content

  @else if $point == tablet
    @media ($tablet)
      @content

  @else if $point == medium
    @media ($medium)
      @content

  @else if $point == classic
    @media ($classic)
      @content

  @else
    @media ($point)
      @content
