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avrahamsociety/main.js
Lazy Hippopotamus e7d8d215b4 initial commit
2023-06-06 14:29:46 -04:00

35 lines
1.4 KiB
JavaScript

const scrollchecks = () => {
var el = document.getElementById("header");
el.style.backgroundPositionY = 50 + (document.documentElement.scrollTop/el.scrollHeight) / 2 * 100 + "%";
Array.from(document.getElementsByClassName("scrolly")).forEach(el => {
let box = el.getBoundingClientRect();
if (box.bottom < 0 || box.top >= window.innerHeight) {
el.classList.add("scrolly-out");
el.classList.remove("scrolly-in");
el.classList.remove("scrolly-onedge");
}
else {
el.classList.remove("scrolly-out");
el.classList.add("scrolly-in");
el.classList.add("scrolly-entered");
if (box.top <= 0 || box.bottom >= window.innerHeight) {
el.classList.add("scrolly-onedge");
}
else {
el.classList.remove("scrolly-onedge");
}
}
if (box.top + box.height / 2 <= window.innerHeight / 2) {
el.classList.add("scrolly-tophalf");
el.classList.remove("scrolly-bottomhalf");
}
else {
el.classList.remove("scrolly-tophalf");
el.classList.add("scrolly-bottomhalf");
}
});
};
window.addEventListener("scroll", scrollchecks);
window.addEventListener("wheel", scrollchecks);
window.addEventListener("resize", scrollchecks);
window.addEventListener("load", scrollchecks);