Answers for "if at bottom scroll to bottom html"

check if scrolled to bottom of div

window.addEventListener("scroll", () => {
    var offset = element.getBoundingClientRect().top - element.offsetParent.getBoundingClientRect().top;
    const top = window.pageYOffset + window.innerHeight - offset;

    if (top === element.scrollHeight) {
        console.log("bottom");
    }
}, { passive: false });

scroll start from bottom css

.container {
  display: flex;
  flex-direction: column-reverse;
}