diff --git a/basics-10-styling-starting-setup/app.js b/basics-10-styling-starting-setup/app.js
index f8abbdc..24d9260 100644
--- a/basics-10-styling-starting-setup/app.js
+++ b/basics-10-styling-starting-setup/app.js
@@ -11,11 +11,11 @@ const app = Vue.createApp({
     methods: {
         boxSelected(box) {
             if (box === "A") {
-                this.boxASelected = true;
+                this.boxASelected = !this.boxASelected;
             } else if (box === "B") {
-                this.boxBSelected = true;
+                this.boxBSelected = !this.boxBSelected;
             } else if (box === "C") {
-                this.boxCSelected = true;
+                this.boxCSelected = !this.boxCSelected;
             }
         },
     },