Support Svelte 4

[VaelVictus]

I can confirm everything's working as expected in Svelte 4.

[VaelVictus]

Unfortunately I could no longer wait for this to hit npm, and built this with the help of AI. Hopefully it will be of use to anyone who doesn't need the extra functionality from this package.

const animateScroll = {
        getAbsoluteTop: function(element) {
            let top = 0;
            while (element) {
                top += element.offsetTop || 0;
                element = element.offsetParent;
            }
            return top;
        },
        scrollTo: function({element, duration = 1000, offset = 0, container = 'body'}) {
            const containerElement = container === 'body' ? document.documentElement : document.querySelector(container);
            const containerTop = this.getAbsoluteTop(containerElement);
            const start = containerElement.scrollTop;
            const target = this.getAbsoluteTop(element) - containerTop + offset;
            const distance = target - start;
            const startTime = performance.now();
            let nextStep;

            const easeInOutQuad = function(time) {
                time /= duration / 2;
                if (time < 1) return distance / 2 * time * time + start;
                time--;
                return -distance / 2 * (time * (time - 2) - 1) + start;
            };

            let scroll = (currentTime) => {
                const timeElapsed = currentTime - startTime;
                nextStep = easeInOutQuad(timeElapsed);

                containerElement.scrollTop = nextStep;

                if(timeElapsed < duration) {
                    requestAnimationFrame(scroll);
                }
            };
            
            requestAnimationFrame(scroll);
        }
    };

Usage
animateScroll.scrollTo({element: document.querySelector(`#your_element`), duration: 750, offset: -95, container: '#your_container'});

[kevbook]

You can just use the native scrollIntoView now https://svelte.dev/repl/e073dc93fb3347848062a531271e497f