window.addEventListener("load", function(){
	if( self.location.href.indexOf('/kontakt') != -1 ){
		contactPage();
	}
}, false);

function contactPage(){
	var mainDiv = document.getElementById('main');
	mainDiv.innerHTML = mainDiv.innerHTML.replace('gk [at] develope pl', 'gk' + '@' + 'develope' + '.pl');
}