diff --git a/src/wp-admin/css/common.css b/src/wp-admin/css/common.css
index 022a276bb7..095593590f 100644
--- a/src/wp-admin/css/common.css
+++ b/src/wp-admin/css/common.css
@@ -1566,11 +1566,7 @@ div.error {
 	line-height: 1.4;
 	padding: 11px 15px;
 	font-size: 14px;
-	text-align: left;
 	margin: 25px 20px 0 2px;
-	background-color: #fff;
-	border-left: 4px solid #ffba00;
-	box-shadow: 0 1px 1px 0 rgba(0, 0, 0, 0.1);
 }
 
 ul#dismissed-updates {
diff --git a/src/wp-admin/includes/ms.php b/src/wp-admin/includes/ms.php
index a1548f9bb0..6a2efa23b7 100644
--- a/src/wp-admin/includes/ms.php
+++ b/src/wp-admin/includes/ms.php
@@ -703,7 +703,7 @@ function site_admin_notice() {
 	}
 
 	if ( get_site_option( 'wpmu_upgrade_site' ) != $wp_db_version ) {
-		echo "<div class='update-nag'>" . sprintf(
+		echo "<div class='update-nag notice notice-warning inline'>" . sprintf(
 			/* translators: %s: URL to Upgrade Network screen. */
 			__( 'Thank you for Updating! Please visit the <a href="%s">Upgrade Network</a> page to update all your sites.' ),
 			esc_url( network_admin_url( 'upgrade.php' ) )
diff --git a/src/wp-admin/includes/update.php b/src/wp-admin/includes/update.php
index 92a14dc61f..0d9fab024b 100644
--- a/src/wp-admin/includes/update.php
+++ b/src/wp-admin/includes/update.php
@@ -318,7 +318,8 @@ function update_nag() {
 			$cur->current
 		);
 	}
-	echo "<div class='update-nag'>$msg</div>";
+
+	echo "<div class='update-nag notice notice-warning inline'>$msg</div>";
 }
 
 /**
@@ -764,7 +765,7 @@ function maintenance_nag() {
 		$msg = __( 'An automated WordPress update has failed to complete! Please notify the site administrator.' );
 	}
 
-	echo "<div class='update-nag'>$msg</div>";
+	echo "<div class='update-nag notice notice-warning inline'>$msg</div>";
 }
 
 /**