=grid-size($property, $spacing-key: 1, $factor: 1)
  // Get value
  $value: nth($spacing-list, $spacing-key)
  // Set property value
  #{$property}: nth($value,1) * $factor
  // Respond to different screen sizes
  +respond-to(medium)
    #{$property}: nth($value,2) * $factor
  +respond-to(large)
    #{$property}: nth($value,3) * $factor

=grid-line-height($factor: 1)
  +grid-size(line-height, 1, $factor)

=grid-line-height-s($factor: 1)
  +grid-size(line-height, 2, $factor)

=grid-height($factor: 1)
  +grid-size(height, 1, $factor)

=grid-height-s($factor: 1)
  +grid-size(height, 2, $factor)

=grid-max-height($factor: 1)
  +grid-size(max-height, 1, $factor)

=grid-max-height-s($factor: 1)
  +grid-size(max-height, 2, $factor)

=grid-width($factor: 1)
  +grid-size(width, 1, $factor)

=grid-width-s($factor: 1)
  +grid-size(width, 2, $factor)