fix spacer vars

scss/_utilities.scss

@@ -44,7 +44,7 @@
 .m-b-0 { margin-bottom: 0; }
 .m-l-0 { margin-left:   0; }
 
-.m-a { margin:        $spacer-base; }
+.m-a { margin:        $spacer; }
 .m-t { margin-top:    $spacer-y; }
 .m-r { margin-right:  $spacer-x }
 .m-b { margin-bottom: $spacer-y; }
@@ -92,7 +92,7 @@
 .p-b-0 { padding-bottom: 0; }
 .p-l-0 { padding-left:   0; }
 
-.p-a { padding:        $spacer-base; }
+.p-a { padding:        $spacer; }
 .p-t { padding-top:    $spacer-y; }
 .p-r { padding-right:  $spacer-x }
 .p-b { padding-bottom: $spacer-y; }

scss/_variables.scss

@@ -43,6 +43,9 @@ $enable-gradients:           false !default;
 $enable-transitions:         true !default;
 
 $spacer:                     1rem !default;
+$spacer-x:                   $spacer !default;
+$spacer-y:                   $spacer !default;
+
 $border-width:               .075rem !default;
 
 $use-hover-media-query:      false !default;