app.sass

div
  padding: 10px
  
  @include for-size(desktop-up)
    padding: 20px

media.sass

@mixin for-size($size)
  // Upper boundaries
  $phone-upper-boundary: 600px
  $tablet-portrait-upper-boundary: 900px
  $tablet-landscape-upper-boundary: 1200px
  $desktop-upper-boundary: 1800px
  
  @if $size == phone-only
    @media (max-width: #{$phone-upper-boundary - 1}) 
      @content
      
  @else if $size == tablet-portrait-up
    @media (min-width: #{$phone-upper-boundary}) 
      @content
  @else if $size == tablet-portrait-only
    @media (min-width: #{$phone-upper-boundary}) and (max-width: #{$tablet-portrait-upper-boundary - 1}) 
      @content
      
  @else if $size == tablet-landscape-up
    @media (min-width: $tablet-portrait-upper-boundary) 
      @content
  @else if $size == tablet-landscape-only
    @media (min-width: $tablet-portrait-upper-boundary) and (max-width: #{$tablet-landscape-upper-boundary - 1})
      @content
      
  @else if $size == desktop-up
    @media (min-width: $tablet-landscape-upper-boundary) 
      @content
  @else if $size == desktop-only
    @media (min-width: $tablet-landscape-upper-boundary) and (max-width: #{$desktop-upper-boundary - 1}) 
      @content
      
  @else if $size == bid-desktop-up
    @media (min-width: $desktop-upper-boundary)
      @content