SassMeister-input.scss

// Sass v3.2.7
// Susy v1.0.5

@import "susy";

@mixin respond-to($primary) {
  @if $primary == small {
    @media screen and (min-width: 500px) { 
        $total-columns: 12;
        @content; 
        }
  }
  @else if $primary == large {
    @media screen and (min-width: 900px) { 
        $total-columns: 2;
        @content; 
        }
  }
}

@include respond-to(small) {
 div {
     @include span-columns(1)
 } 
}

@include respond-to(large) {
 div {
     @include span-columns(1)
 } 
}

SassMeister-output.css

@media screen and (min-width: 500px) {
  div {
    width: 6.77966%;
    float: left;
    margin-right: 1.69492%;
    display: inline;
  }
}
@media screen and (min-width: 900px) {
  div {
    width: 44.44444%;
    float: left;
    margin-right: 11.11111%;
    display: inline;
  }
}