@mixin screen($resMin, $resMax)
{
  @media screen and (min-width: $resMin) and (max-width: $resMax)
  {
    @content;
  }
}

@mixin max-screen($res)
{
  @media screen and (max-width: $res)
  {
    @content;
  }
}

@mixin min-screen($res)
{
  @media screen and (min-width: $res)
  {
    @content;
  }
}

@mixin screen-height($resMin, $resMax)
{
  @media screen and (min-height: $resMin) and (max-height: $resMax)
  {
    @content;
  }
}

@mixin max-screen-height($res)
{
  @media screen and (max-height: $res)
  {
    @content;
  }
}

@mixin min-screen-height($res)
{
  @media screen and (min-height: $res)
  {
    @content;
  }
}


// hdpi
//----------------------------------------------------- 

// Based on bourbon hidpi-media-queries file (https://github.com/thoughtbot/bourbon/blob/master/app/assets/stylesheets/css3/_hidpi-media-query.scss)
// HIDPI mixin. Default value set to 1.3 to target Google Nexus 7 (http://bjango.com/articles/min-device-pixel-ratio/)

@mixin hdpi($ratio: 1.3)
{
  @media only screen and (-webkit-min-device-pixel-ratio: $ratio),
  only screen and (min--moz-device-pixel-ratio: $ratio),
  only screen and (-o-min-device-pixel-ratio: #{$ratio}/1),
  only screen and (min-resolution: #{round($ratio*96)}dpi),
  only screen and (min-resolution: #{$ratio}dppx)
  {
    @content;
  }
}

// iphone
//----------------------------------------------------- 

@mixin iphone3($orientation: all)
{
  $deviceMinWidth: 320px;
  $deviceMaxWidth: 480px;
  $devicePixelRatio: 1;

  @if $orientation == all
  {
    @media only screen and (min-device-width: $deviceMinWidth) and (max-device-width: $deviceMaxWidth)
    and (-webkit-device-pixel-ratio: $devicePixelRatio)
    {
      @content;
    }
  }
  @else
  {
    @media only screen and (min-device-width: $deviceMinWidth) and (max-device-width: $deviceMaxWidth)
    and (-webkit-device-pixel-ratio: $devicePixelRatio) and (orientation:#{$orientation})
    {
      @content;
    }
  }
}

// iphone-retina
//----------------------------------------------------- 

@mixin iphone4($orientation: all)
{
  $deviceMinWidth: 320px;
  $deviceMaxWidth: 480px;
  $devicePixelRatio: 2;
  $deviceAspectRatio: '2/3';

  @if $orientation == all
  {
    @media only screen and (min-device-width: $deviceMinWidth) and (max-device-width: $deviceMaxWidth)
    and (-webkit-device-pixel-ratio: $devicePixelRatio) and (device-aspect-ratio: $deviceAspectRatio)
    {
      @content;
    }
  }
  @else
  {
    @media only screen and (min-device-width: $deviceMinWidth) and (max-device-width: $deviceMaxWidth)
    and (-webkit-device-pixel-ratio: $devicePixelRatio) and (device-aspect-ratio: 2/3) and (orientation:#{$orientation})
    {
      @content;
    }
  }
}

// iphone-5
//-----------------------------------------------------

@mixin iphone5($orientation: all)
{
  $deviceMinWidth: 320px;
  $deviceMaxWidth: 568px;
  $devicePixelRatio: 2;
  $deviceAspectRatio: '40/71';

  @if $orientation == all
  {
    @media only screen and (min-device-width: $deviceMinWidth) and (max-device-width: $deviceMaxWidth)
    and (-webkit-device-pixel-ratio: $devicePixelRatio) and (device-aspect-ratio: $deviceAspectRatio)
    {
      @content;
    }
  }
  @else
  {
    @media only screen and (min-device-width: $deviceMinWidth) and (max-device-width: $deviceMaxWidth)
    and (-webkit-device-pixel-ratio: $devicePixelRatio) and (device-aspect-ratio: $deviceAspectRatio) and (orientation:#{$orientation})
    {
      @content;
    }
  }
}

// ipads (all)
//-----------------------------------------------------

@mixin ipad($orientation: all)
{
  $deviceMinWidth: 768px;
  $deviceMaxWidth: 1024px;

  @if $orientation == all
  {
    @media only screen and (min-device-width: $deviceMinWidth) and (max-device-width: $deviceMaxWidth)
    {
      @content;
    }
  }
  @else
  {
    @media only screen and (min-device-width: $deviceMinWidth) and (max-device-width: $deviceMaxWidth)
    and (orientation:#{$orientation})
    {
      @content;
    }
  }
}

// ipad-retina
//-----------------------------------------------------

@mixin ipad-retina($orientation: all)
{
  $deviceMinWidth: 768px;
  $deviceMaxWidth: 1024px;
  $devicePixelRatio: 2;

  @if $orientation == all
  {
    @media only screen and (min-device-width: $deviceMinWidth) and (max-device-width: $deviceMaxWidth)
    and (-webkit-device-pixel-ratio: $devicePixelRatio)
    {
      @content;
    }
  }
  @else
  {
    @media only screen and (min-device-width: $deviceMinWidth) and (max-device-width: $deviceMaxWidth)
    and (-webkit-device-pixel-ratio: $devicePixelRatio) and (orientation:#{$orientation})
    {
      @content;
    }
  }
}