Sass mixin for styling scrollbars in webkit by Hugo Giraudel (http://codepen.io/HugoGiraudel/pen/KFDuB)

scrollbar-mixin

/**
 * Mixin scrollbar
 */
@mixin scrollbar($size, $primary, $secondary: lighten($primary, 25%)) {
  ::-webkit-scrollbar {
		width:  $size;
		height: $size;
	}

	::-webkit-scrollbar-thumb {
		background: $primary;
	}

	::-webkit-scrollbar-track {
		background: $secondary;
	}
  
  // For Internet Explorer
  body {
    scrollbar-face-color: $primary;
    scrollbar-track-color: $secondary;
  }
}

/**
 * Call the damn thing
 */
@include scrollbar(.5em, tomato);

/** 
 * Force scrollbars
 */
body {
  height: 3000px;
  width:  3000px;
}