Custom desktop grid in Foundation

_desktop.sass

$total-columns: 12

/* Desktop grid */
@media #{$medium} 
  @for $i from 1 through $total-columns 
    .desktop#{-$i}
      @include grid-column($columns:$i,$collapse:null,$float:false)

  @for $i from 0 through $total-columns - 1  
    .row .desktop-offset-#{$i}
      @include grid-column($offset:$i, $collapse:null,$float:false)

  @for $i from 1 through $total-columns - 1  
    .push#{-$i}
      @include grid-column($push:$i, $collapse:null, $float:false)
    .pull#{-$i}
      @include grid-column($pull:$i, $collapse:null, $float:false)

  .column.desktop-centered,
  .columns.desktop-centered
    @include grid-column($center:true, $collapse:null, $float:false)

  .column.desktop-uncentered,
  .columns.desktop-uncentered 
    margin-#{$default-float}: 0
    margin-#{$opposite-direction}: 0
    float: $default-float !important

  .column.desktop-uncentered.opposite,
  .columns.desktop-uncentered.opposite 
    float: $opposite-direction !important