SassMeister-input.scss

// ----
// Sass (v3.3.8)
// Compass (v1.0.0.alpha.19)
// ----

$red: #ff4242;

// Declare this variable early 
$parent-classes: ();

// This mixin holds the style code you want to repeat
@mixin grid() {
  width: 100%;
  &-item {
    width: 33%;
    padding: 1em;
    &-title {
      color: $red;
      text-transform: uppercase;
    }
  }
}

// In _products.scss:
$parent-classes: append($parent-classes, #{'.products-grid'}, comma);

// In _services.scss:
$parent-classes: append($parent-classes, #{'.services-grid'}, comma);

// In _industries.scss:
$parent-classes: append($parent-classes, #{'.industries-grid'}, comma);

// Do this near the end: 
#{$parent-classes} {
  @include grid();
}

/* Read the detailed explanation behind this gist here: 
http://jamessteinbach.com/css/sass/creating-repeatable-style-pattern-sass-placeholders-vs-mixins/
*/

SassMeister-output.css

.products-grid, .services-grid, .industries-grid {
  width: 100%;
}
.products-grid-item, .services-grid-item, .industries-grid-item {
  width: 33%;
  padding: 1em;
}
.products-grid-item-title, .services-grid-item-title, .industries-grid-item-title {
  color: #ff4242;
  text-transform: uppercase;
}

/* Read the detailed explanation behind this gist here: 
http://jamessteinbach.com/css/sass/creating-repeatable-style-pattern-sass-placeholders-vs-mixins/
*/