add $grid__columns variable for custom grid definition

Author: denniserdmann

files/nutshell/scss/mixins/_general.scss

@@ -11,6 +11,7 @@
 // --------------------------------------------------
 
 // VARIABLES
+$grid__columns: 12 !default;
 
 // USED FROM _variables.scss
 
@@ -35,9 +36,9 @@
 }
 
 // make-row
-@mixin make-row($grid__columns) {
+@mixin make-row($total__columns: $grid__columns) {
   display: grid;
-  grid-template-columns: repeat($grid__columns, 1fr);
+  grid-template-columns: repeat($total__columns, 1fr);
   grid-column-gap: var(--grid__gutter);
   grid-auto-columns: 1fr;