diff --git a/packages/frontend/src/themes/_dark.json5 b/packages/frontend/src/themes/_dark.json5
index c82a956868..a310fb716f 100644
--- a/packages/frontend/src/themes/_dark.json5
+++ b/packages/frontend/src/themes/_dark.json5
@@ -89,7 +89,6 @@
 		X11: 'rgba(0, 0, 0, 0.3)',
 		X12: 'rgba(255, 255, 255, 0.1)',
 		X13: 'rgba(255, 255, 255, 0.15)',
-		X14: ':alpha<0.5<@navBg',
 		X15: ':alpha<0<@panel',
 		X16: ':alpha<0.7<@panel',
 		X17: ':alpha<0.8<@bg',
diff --git a/packages/frontend/src/themes/_light.json5 b/packages/frontend/src/themes/_light.json5
index 63bc030916..827a935a0b 100644
--- a/packages/frontend/src/themes/_light.json5
+++ b/packages/frontend/src/themes/_light.json5
@@ -89,7 +89,6 @@
 		X11: 'rgba(0, 0, 0, 0.1)',
 		X12: 'rgba(0, 0, 0, 0.1)',
 		X13: 'rgba(0, 0, 0, 0.15)',
-		X14: ':alpha<0.5<@navBg',
 		X15: ':alpha<0<@panel',
 		X16: ':alpha<0.7<@panel',
 		X17: ':alpha<0.8<@bg',
diff --git a/packages/frontend/src/ui/_common_/navbar-for-mobile.vue b/packages/frontend/src/ui/_common_/navbar-for-mobile.vue
index 87e9e45e63..e80d5fd399 100644
--- a/packages/frontend/src/ui/_common_/navbar-for-mobile.vue
+++ b/packages/frontend/src/ui/_common_/navbar-for-mobile.vue
@@ -82,6 +82,8 @@ function more() {
 
 <style lang="scss" module>
 .root {
+	--nav-bg-transparent: color-mix(in srgb, var(--navBg), transparent 50%);
+
 	display: flex;
 	flex-direction: column;
 }
@@ -91,7 +93,7 @@ function more() {
 	top: 0;
 	z-index: 1;
 	padding: 20px 0;
-	background: var(--X14);
+	background: var(--nav-bg-transparent);
 	-webkit-backdrop-filter: var(--blur, blur(8px));
 	backdrop-filter: var(--blur, blur(8px));
 }
@@ -125,7 +127,7 @@ function more() {
 	position: sticky;
 	bottom: 0;
 	padding: 20px 0;
-	background: var(--X14);
+	background: var(--nav-bg-transparent);
 	-webkit-backdrop-filter: var(--blur, blur(8px));
 	backdrop-filter: var(--blur, blur(8px));
 }
diff --git a/packages/frontend/src/ui/_common_/navbar.vue b/packages/frontend/src/ui/_common_/navbar.vue
index 8307da0d42..2b116909ba 100644
--- a/packages/frontend/src/ui/_common_/navbar.vue
+++ b/packages/frontend/src/ui/_common_/navbar.vue
@@ -111,6 +111,7 @@ function more(ev: MouseEvent) {
 .root {
 	--nav-width: 250px;
 	--nav-icon-only-width: 80px;
+	--nav-bg-transparent: color-mix(in srgb, var(--navBg), transparent 50%);
 
 	flex: 0 0 var(--nav-width);
 	width: var(--nav-width);
@@ -144,7 +145,7 @@ function more(ev: MouseEvent) {
 		top: 0;
 		z-index: 1;
 		padding: 20px 0;
-		background: var(--X14);
+		background: var(--nav-bg-transparent);
 		-webkit-backdrop-filter: var(--blur, blur(8px));
 		backdrop-filter: var(--blur, blur(8px));
 	}
@@ -187,7 +188,7 @@ function more(ev: MouseEvent) {
 		position: sticky;
 		bottom: 0;
 		padding-top: 20px;
-		background: var(--X14);
+		background: var(--nav-bg-transparent);
 		-webkit-backdrop-filter: var(--blur, blur(8px));
 		backdrop-filter: var(--blur, blur(8px));
 	}
@@ -378,7 +379,7 @@ function more(ev: MouseEvent) {
 		top: 0;
 		z-index: 1;
 		padding: 20px 0;
-		background: var(--X14);
+		background: var(--nav-bg-transparent);
 		-webkit-backdrop-filter: var(--blur, blur(8px));
 		backdrop-filter: var(--blur, blur(8px));
 	}
@@ -408,7 +409,7 @@ function more(ev: MouseEvent) {
 		position: sticky;
 		bottom: 0;
 		padding-top: 20px;
-		background: var(--X14);
+		background: var(--nav-bg-transparent);
 		-webkit-backdrop-filter: var(--blur, blur(8px));
 		backdrop-filter: var(--blur, blur(8px));
 	}