Decrease horizontal margins on pages

modules/core/ui/theme/css/regions.css

@@ -0,0 +1,16 @@
+/* Decrease the horizontal margin on medium to large screens. Gin uses xxl. */
+@media (min-width: 48em) {
+  .toolbar-tray-open:not(.toolbar-vertical) .layout-container,
+  body:not(.toolbar-tray-open) .layout-container {
+    margin-left: var(--gin-spacing-m) !important;
+    margin-right: var(--gin-spacing-m) !important;
+  }
+}
+
+/*
+  Override gin style that moves user toolbar icon to the right.
+  With our narrower margins this overflows and adds a horizontal scroll bar.
+ */
+.toolbar-id--toolbar-icon-user {
+  margin-right: 0 !important;
+}

modules/core/ui/theme/farm_ui_theme.libraries.yml

@@ -36,6 +36,10 @@ quick:
   css:
     theme:
       css/quick.css: { }
+regions:
+  css:
+    theme:
+      css/regions.css: { }
 toolbar:
   css:
     theme:

modules/core/ui/theme/farm_ui_theme.module

@@ -109,6 +109,13 @@ function farm_ui_theme_preprocess_log__full(&$variables) {
   $variables['#attached']['library'][] = 'farm_ui_theme/layout';
 }
 
+/**
+ * Implements hook_preprocess_HOOK().
+ */
+function farm_ui_theme_preprocess_page(&$variables) {
+  $variables['#attached']['library'][] = 'farm_ui_theme/regions';
+}
+
 /**
  * Implements hook_preprocess_HOOK().
  */