diff --git a/nexus_constructor/ui_utils.py b/nexus_constructor/ui_utils.py
index 2ec41faad..09a916bc5 100644
--- a/nexus_constructor/ui_utils.py
+++ b/nexus_constructor/ui_utils.py
@@ -93,7 +93,7 @@ def validate_line_edit(
     if is_valid:
         line_edit.setStyleSheet("")
     else:
-        line_edit.setStyleSheet("QLineEdit {{ background-color: #f6989d }}")
+        line_edit.setStyleSheet("QLineEdit { background-color: #f6989d }")
     if "Suggestion" in tooltip_on_reject and callable(suggestion_callable):
         tooltip_on_reject += suggestion_callable()
     line_edit.setToolTip(tooltip_on_accept) if is_valid else line_edit.setToolTip(