I need help doing a slow scroll right with a scroll.

The page scrolls down normally, only one container goes to the right. I managed to scroll to the right but the problem is that it looks nasty because it kind of cuts. I tried to use jQuery (animate) but it scrolled to the point the scroll sent and then it didn't look nice again.

    const scrollContainer = document.querySelector("article");

    scrollContainer.addEventListener("wheel", (evt) => {
        evt.preventDefault();
        $('.header_scroll').animate( { scrollLeft: '+='+evt.deltaY/2 }, 100);
        // scrollContainer.scrollLeft += evt.deltaY;   -- that was before
    });