This is a example of a mixin that will output a certain font-family depending on the size being sent in as an argument. IN this case its 18px so the font-family will be Georgia, serif
@mixin family($size){ font-size: $size; @if $size <= 16px { font-family: Arial, sans-serif; } @else if $size <= 24px { font-family: Georgia, serif; } @else { font-family: Helvetica, sans-serif; } } .switch { @include family(18px); }