I get undefined with elem.srollY. Where is the mistake?

Question

JavaScript

Hey!
Here is the demo.
I'm trying to display the distance in pixels from the top edge of the window to the element with the item5 class when scrolling.
But I get undefined.
Can't figure out why

console.log(window.scrollY); // Выдаёт расстояние в пикселях
console.log(elem.scrollY); // А тут получаю undefined.

Thank you!

Answer 1

scrollY — свойство только для чтения интерфейса Window