diff --git a/frontend/src/app/ntt-gantt/ntt-gantt.component.css b/frontend/src/app/ntt-gantt/ntt-gantt.component.css
index 21aee72..95418f7 100644
--- a/frontend/src/app/ntt-gantt/ntt-gantt.component.css
+++ b/frontend/src/app/ntt-gantt/ntt-gantt.component.css
@@ -406,7 +406,7 @@
 } */
 
 .mat-button-toggle-checked {
-  background: linear-gradient(45deg, #ff9800, #ef6c00); /* Gradient background */
+  background-color:#ef6c00; /* Gradient background */
   color: white;
   position: relative; /* Needed for the shadow effect */
 }