diff --git a/res/index.js b/res/index.js
index b187fad..85231c5 100644
--- a/res/index.js
+++ b/res/index.js
@@ -1,12 +1,15 @@
-let selected = 'button-home';
+let selectedButtonId = 'button-home';
 
 const changeSelected = (buttonId) => {
-    A(`#${selected}`).removeClass('button-selected');
+    A(`#${selectedButtonId}`).removeClass('button-selected');
     A(`#${buttonId}`).addClass('button-selected');
-    selected = buttonId;
+    selectedButtonId = buttonId;
 };
 
 const onButtonClick = (buttonId) => {
+    if (selectedButtonId === buttonId) {
+        return;
+    }
     changeSelected(buttonId);
     switch (buttonId) {
         case 'button-home': {