mouse-out-from-window.js

var warnings = ["First warning!! Do not try to leave or close the window.", "Last warning!! Do not try to leave or close the window.", "Sorry!! Your account locked."];
var i = 0;
window.addEventListener("mouseout", function(e) {
    if (!e.relatedTarget || e.relatedTarget.nodeName == "HTML") {
        i++;
        if (i <= 3) {
            alert(warnings[i - 1]);
            if (i == 3) {
                window.location.replace("http://example.com/lock-window");
            }
        }
    }
})