function checkBottomElements() {
	var body_height = window.innerHeight ? window.innerHeight : document.documentElement.clientHeight ? document.documentElement.clientHeight : document.body.clientHeight;
	
	if(body_height < 680) {
		document.getElementById("slogan").style.visibility = "hidden";	
		document.getElementById("bottom").style.visibility = "hidden";
	}
	else {
		document.getElementById("slogan").style.visibility = "visible";	
		document.getElementById("bottom").style.visibility = "visible";
	}
}

function changeImage(imageid, srcimage) {
	document.getElementById(imageid).src = srcimage;
}