Flying Eagle

function pinterIstvan() {
    var sasDiv = document.getElementById("sasDiv");

    if (!sasDiv) {
        sasDiv = document.createElement("div");
        sasDiv.setAttribute("id", "sasDiv");
        sasDiv.style.position = "fixed";
        sasDiv.style.zIndex = "99999999";

        var sasImg = document.createElement("img");
        sasImg.src = "https://i.imgur.com/cGCBuxM.gif";

        sasDiv.appendChild(sasImg);

        var sasCopyright = document.createElement("div");
        sasCopyright.innerHTML = "Made by István Pintér";
        sasCopyright.style.color = "transparent";

        sasDiv.appendChild(sasCopyright);

        var body = document.body;

        body.insertBefore(sasDiv, body.childNodes[0]);
    }

    var lft = -sasDiv.offsetWidth;
    var moveSas = function() {
        lft += 5;

        if (lft > document.body.clientWidth) lft = -sasDiv.offsetWidth;

        sasDiv.style.left = lft + "px";
        requestAnimationFrame(moveSas);
    }

    requestAnimationFrame(moveSas);
}