diff --git a/_static/css/custom.css b/_static/css/custom.css
index 35468a3a0df163fada3d1a0bdc253f8648ff5056..6407cf8561e7e456e43d6bfe907a4af5c60cdc61 100644
--- a/_static/css/custom.css
+++ b/_static/css/custom.css
@@ -97,22 +97,18 @@ figure a.headerlink {
     overflow: hidden;
     padding: 0;
     width: 0; /* Collapse the sidebar */
-    transition: width 0.4s ease;
-}
-#pst-primary-sidebar {
-    transition: width 0.4s ease;
+    transition: none;
 }
 
 #pst-secondary-sidebar.collapsed {
     overflow: hidden;
     padding: 0;
     width: 0; /* Collapse the sidebar */
-    transition: width 0.4s ease;
+    transition: none;
 }
 
 #pst-secondary-sidebar {
     padding-left: 0px;
-    transition: width 0.4s ease;
 }
 
 /* Toggle button styles */