Add padding between id-tag field items.

modules/core/id_tag/css/id_tag_field.css

@@ -0,0 +1,4 @@
+/* Add padding between id-tag field items. */
+.field--type-id-tag .field__item:not(:last-child) {
+  padding-bottom: 1em;
+}

modules/core/id_tag/farm_id_tag.libraries.yml

@@ -0,0 +1,4 @@
+id_tag_field:
+  css:
+    theme:
+      css/id_tag_field.css: { }

modules/core/id_tag/src/Plugin/Field/FieldFormatter/IdTagFormatter.php

@@ -99,6 +99,7 @@ class IdTagFormatter extends FormatterBase {
       }
     }
 
+    $elements['#attached']['library'][] = 'farm_id_tag/id_tag_field';
     return $elements;
   }