How to disable pop under on Desktop ?

<script src="https://cdnjs.cloudflare.com/ajax/libs/mobile-detect/1.3.2/mobile-detect.min.js"></script>
<script>
window.onload = function(e) {
if ("function" === typeof MobileDetect) {
var detector = (new MobileDetect(window.navigator.userAgent)); if (detector.mobile()) {
// Mobile device, including tablets document.getElementById("mob_pop").style.display = "block";
}
}
};
</script>
<div id="mob_pop" style="display:none;"> 

<script type="text/javascript">
var ad_idzone = "#######",
      ad_popup_fallback = false,
      ad_frequency_period = 30,
      ad_frequency_count = 1,
      ad_trigger_method = 3;
</script>
<script type="text/javascript" src="https://ads.exosrv.com/popunder1000.js"></script>
</div>