diff --git a/src/apprt/gtk/style-dark.css b/src/apprt/gtk/style-dark.css
index a9aa2dcc0..b56fa14f2 100644
--- a/src/apprt/gtk/style-dark.css
+++ b/src/apprt/gtk/style-dark.css
@@ -1,3 +1,8 @@
 .transparent {
   background-color: transparent;
 }
+
+separator {
+  background-color: rgba(36, 36, 36, 1);
+  background-clip: content-box;
+}
diff --git a/src/apprt/gtk/style.css b/src/apprt/gtk/style.css
index 188e26671..65dc0c075 100644
--- a/src/apprt/gtk/style.css
+++ b/src/apprt/gtk/style.css
@@ -36,3 +36,8 @@ label.size-overlay.hidden {
 .transparent {
   background-color: transparent;
 }
+
+separator {
+  background-color: rgba(250, 250, 250, 1);
+  background-clip: content-box;
+}