NetflixClone/src/utils/animations.js

export const scrollTo = (element, to, duration, scrollToDone = null) => {
    Math.easeInOutQuad = (t, b, c, d) => {
        t /= d / 2;
        if (t < 1) return c / 2 * t * t + b;
        t--;
        return -c / 2 * (t * (t - 2) - 1) + b;
    };

    let start = element.scrollLeft,
        change = to - start,
        currentTime = 0,
        increment = 20;

    const animateScroll = () => {
        currentTime += increment;
        const val = Math.easeInOutQuad(currentTime, start, change, duration);
        element.scrollLeft = val;
        if (currentTime < duration) {
            setTimeout(animateScroll, increment);
        } else {
            if (scrollToDone) scrollToDone();
        }
    };
    animateScroll();
}