fix: change deprecated pageYOffset to scrollY in BackToTopButton

Author: nikohoffren

components/buttons/BackToTopButton.tsx

@@ -6,7 +6,7 @@ const BackToTopButton = () => {
 
   useEffect(() => {
     const toggleVisibility = () => {
-      if (window.pageYOffset > 300) {
+      if (window.scrollY > 300) {
         setIsVisible(true)
       } else {
         setIsVisible(false)