document.getElementById("popup-box").style.display="block";

olmazsa

var acalim = document.getElementById("myDIV");
acalim.removeClass("is-hide");

ornek;

window.function () {
var igt=Date.now();
if(localStorage.getItem("igz")==""){
var tt=igt;
localStorage.setItem("igz",igt);
}else{ var tt=localStorage.getItem("igz"); }
var kzam=(tt*1)+20000;
// var kzam=(tt*1)+86400000;
if(igt> kzam){
document.getElementById("popup-box").style.display="block";
localStorage.setItem("igz",igt);
}
}

ikinci örnek
window.function () {
var igt=Date.now();
if(localStorage.getItem("igz")==""){
var tt=igt;
localStorage.setItem("igz",igt);
}else{ var tt=localStorage.getItem("igz"); }
var kzam=(tt*1)+20000;
// var kzam=(tt*1)+86400000;
if(igt> kzam){
var acalim = document.getElementById("myDIV");
acalim.removeClass("is-hide");
localStorage.setItem("igz",igt);
}
}