Client site footer signature

document.addEventListener('DOMContentLoaded', function(event) {
    function getUrlParameter(sParam){
        var sPageURL = window.location.search.substring(1);
        var sURLVariables = sPageURL.split('&');
        for (var i = 0; i < sURLVariables.length; i++){

            var sParameterName = sURLVariables[i].split('=');

            if (sParameterName[0] == sParam){
                return sParameterName[1];
            }
        }
    }
    var devGet = getUrlParameter('dev');

    if(devGet == 'mrz'){
        var targetDiv = document.getElementById("dev-credit"),
            targetDiv2 = document.getElementsByTagName("footer")[0];

        if(targetDiv !== null && targetDiv !== '') {
           targetDiv.innerHTML = 'Developed with <i class="fa fa-heart"></i> by <a href="http://mashiurz.com" target="_blank">Mashiurz</a>';
        }else{
            targetDiv2.insertAdjacentHTML('beforeend', 'Developed with <i class="fa fa-heart"></i> by <a href="http://mashiurz.com" target="_blank">Mashiurz</a>');
        }

    }
});