move from .gutters-sm to .form-row to be super explicit about intended use case

scss/_forms.scss

@@ -193,6 +193,24 @@ select.form-control-lg {
 }
 
 
+// Form grid
+//
+// Special replacement for our grid system's `.row` for tighter form layouts.
+
+.form-row {
+  display: flex;
+  flex-wrap: wrap;
+  margin-right: -5px;
+  margin-left: -5px;
+
+  > .col,
+  > [class*="col-"] {
+    padding-right: 5px;
+    padding-left: 5px;
+  }
+}
+
+
 // Checkboxes and radios
 //
 // Indent the labels to position radios/checkboxes as hanging controls.

scss/_grid.scss

@@ -42,18 +42,6 @@
       padding-left: 0;
     }
   }
-
-  // Optionally tighten the gutters between columns
-  .gutters-sm {
-    margin-right: -5px;
-    margin-left: -5px;
-
-    > .col,
-    > [class*="col-"] {
-      padding-right: 5px;
-      padding-left: 5px;
-    }
-  }
 }
 
 // Columns