diff --git a/docs/js/upgrade.js b/docs/js/upgrade.js
index 965fb4b..f1eb859 100644
--- a/docs/js/upgrade.js
+++ b/docs/js/upgrade.js
@@ -35,7 +35,7 @@ for (let upgrade of upgrades) {
     hud2.appendChild(button);
 
     button.addEventListener('click', () => {
-        if (nothingness < upgrade.price) return;
+        if (nothingness < price) return;
         counts[upgrade.exec]++;
 
         cc = counts[upgrade.exec];