diff --git a/en/src/css/custom.css b/en/src/css/custom.css
index 6fee110484d..8949d0f9d85 100644
--- a/en/src/css/custom.css
+++ b/en/src/css/custom.css
@@ -166,6 +166,16 @@
   transition: background-color 0.3s ease, border-color 0.3s ease;
 }
 
+.navbar.navbar-sidebar--show {
+  backdrop-filter: none;
+  -webkit-backdrop-filter: none;
+  background-color: var(--ifm-background-color);
+}
+
+.navbar-sidebar {
+  background-color: var(--ifm-background-color);
+}
+
 [data-theme='dark'] .navbar {
   border-bottom-color: rgba(255, 255, 255, 0.06);
 }