Parallax Effect04 - 나타나기

//window.addEventListener("scroll", () => {
//    let scrollTop = window.screenY || window.pageYOffset || document.documentElement.scrollTop;
//
//    document.querySelector(".scrollTop span").innerText = Math.round(scrollTop);
//})

function scroll(){
    let scrollTop = window.screenY || window.pageYOffset || document.documentElement.scrollTop;
    document.querySelector(".scrollTop span").innerText = Math.round(scrollTop);

    //for(let i=1; i<=9; i++){
    //    if(scrollTop > document.getElementById("section"+i).offsetTop-2){
    //    document.getElementById("section"+i).classList.add("show")
    //    }
    //}

    document.querySelectorAll(".content__item").forEach(el => {
        if(scrollTop >= el.offsetTop - window.innerHeight/2){
            el.classList.add("show");
        }
    })

    requestAnimationFrame(scroll);
}
scroll();

• Window.pageYOffset
• Element.scrollTop
• Window.scrollY
• Document.querySelectorAll()
• Math.round()
• Window.innerHeight