diff --git a/tabby-core/src/theme.paper.scss b/tabby-core/src/theme.paper.scss
index c9b6f6ed..767ddce5 100644
--- a/tabby-core/src/theme.paper.scss
+++ b/tabby-core/src/theme.paper.scss
@@ -90,10 +90,6 @@ $list-group-border-radius: 0;
 $pre-bg: $dropdown-bg;
 $pre-color: $dropdown-link-color;
 
-$alert-danger-bg: $body-bg;
-$alert-danger-text: $red;
-$alert-danger-border: $red;
-
 $headings-font-weight: lighter;
 $headings-color: $base0;
 
diff --git a/tabby-core/src/theme.vars.scss b/tabby-core/src/theme.vars.scss
index 1f275d54..32ba0149 100644
--- a/tabby-core/src/theme.vars.scss
+++ b/tabby-core/src/theme.vars.scss
@@ -193,3 +193,7 @@ $modal-content-border-width:        0;
 
 $progress-bg: $table-bg;
 $progress-height: 3px;
+
+$alert-bg-level: 9;
+$alert-border-level: 5;
+$alert-color-level: -5;