diff --git a/bookie/src/app/sales/bill-type/bill-type.component.html b/bookie/src/app/sales/bill-type/bill-type.component.html
index 360a0a9..4d567df 100644
--- a/bookie/src/app/sales/bill-type/bill-type.component.html
+++ b/bookie/src/app/sales/bill-type/bill-type.component.html
@@ -14,7 +14,7 @@
       class="flex flex-col square-button mr-5, mb-5"
       matRipple
       (click)="select('STAFF')"
-      [class.stron-primary]="selected === 'STAFF'"
+      [class.strong-primary]="selected === 'STAFF'"
       [class.primary]="selected !== 'STAFF'"
     >
       <h3>Staff</h3>