diff --git a/packages/kbn-optimizer/src/worker/webpack.config.ts b/packages/kbn-optimizer/src/worker/webpack.config.ts
index fec9032c73a7b..7b4a5b27b78c7 100644
--- a/packages/kbn-optimizer/src/worker/webpack.config.ts
+++ b/packages/kbn-optimizer/src/worker/webpack.config.ts
@@ -176,7 +176,15 @@ export function getWebpackConfig(
                 {
                   loader: 'sass-loader',
                   options: {
-                    webpackImporter: false,
+                    additionalData(content: string, loaderContext: webpack.loader.LoaderContext) {
+                      return `@import ${stringifyRequest(
+                        loaderContext,
+                        Path.resolve(
+                          worker.repoRoot,
+                          `src/core/public/styles/core_app/_globals_${theme}.scss`
+                        )
+                      )};\n${content}`;
+                    },
                     implementation: require('sass-embedded'),
                     sassOptions: {
                       outputStyle: worker.dist ? 'compressed' : 'expanded',
diff --git a/packages/kbn-storybook/src/webpack.config.ts b/packages/kbn-storybook/src/webpack.config.ts
index bfb0f00222bb0..282a41dcbd453 100644
--- a/packages/kbn-storybook/src/webpack.config.ts
+++ b/packages/kbn-storybook/src/webpack.config.ts
@@ -109,6 +109,12 @@ export default ({ config: storybookConfig }: { config: Configuration }) => {
             {
               loader: 'sass-loader',
               options: {
+                additionalData(content: string, loaderContext: any) {
+                  return `@import ${stringifyRequest(
+                    loaderContext,
+                    resolve(REPO_ROOT, 'src/core/public/styles/core_app/_globals_v8light.scss')
+                  )};\n${content}`;
+                },
                 implementation: require('sass-embedded'),
                 sassOptions: {
                   includePaths: [resolve(REPO_ROOT, 'node_modules')],
diff --git a/packages/kbn-unified-field-list/src/containers/unified_field_list_sidebar/field_list_sidebar.scss b/packages/kbn-unified-field-list/src/containers/unified_field_list_sidebar/field_list_sidebar.scss
index 48fb44f1663e3..08402941bf74b 100644
--- a/packages/kbn-unified-field-list/src/containers/unified_field_list_sidebar/field_list_sidebar.scss
+++ b/packages/kbn-unified-field-list/src/containers/unified_field_list_sidebar/field_list_sidebar.scss
@@ -53,7 +53,7 @@
 
 .unifiedFieldListSidebar .unifiedFieldListItemButton {
   &.kbnFieldButton {
-    margin-bottom: $euiSizeXS / 2;
+    margin-bottom: calc($euiSizeXS / 2);
   }
 
   &.domDragDrop-isDraggable {
diff --git a/src/plugins/controls/public/options_list/components/options_list.scss b/src/plugins/controls/public/options_list/components/options_list.scss
index 5fd2ed96f0b30..e0c749441ff6a 100644
--- a/src/plugins/controls/public/options_list/components/options_list.scss
+++ b/src/plugins/controls/public/options_list/components/options_list.scss
@@ -65,7 +65,7 @@
     }
 
     .optionsList__actionsRow {
-      margin: ($euiSizeS / 2) 0 !important;
+      margin: calc($euiSizeS / 2) 0 !important;
 
       .optionsList__actionBarDivider {
         height: $euiSize;