var switch_menu = "false";
function switchMenu() {
	if(switch_menu == "false") {
	    switch_menu = "true";
		document.getElementById('news').style.display = 'none';
    	document.getElementById('login').style.display = 'block';
	}
    else {
    	switch_menu = "false";
        document.getElementById('login').style.display = 'none';
		document.getElementById('news').style.display = 'block';
    }
}
		
function checkContact(f) {
	if (f.namen.value == "" || f.email.value == "" || f.telefon.value == "" || f.nachricht.value == "") {
		if (f.namen.value == "") {
			document.getElementById('namen_err').style.visibility = "visible";
		}
		else {
			document.getElementById('namen_err').style.visibility = "hidden";
		}
		if (f.email.value == "") {
			document.getElementById('email_err').style.visibility = "visible";
		}
		else {
			document.getElementById('email_err').style.visibility = "hidden";
		}
		if (f.telefon.value == "") {
			document.getElementById('telefon_err').style.visibility = "visible";
		}
		else {
			document.getElementById('telefon_err').style.visibility = "hidden";
		}		
		if (f.email.value == "") {
			document.getElementById('nachricht_err').style.visibility = "visible";
		}
		else {
			document.getElementById('nachricht_err').style.visibility = "hidden";
		}						
		return false
	}
	return true
}

function checkGetPassword(f) {
	if (f.login_user.value == "") {
		document.getElementById('login_user_err').style.visibility = "visible";
		return false
	}
	else {
		document.getElementById('login_user_err').style.visibility = "hidden";
		return true
	}
}

function checkCallback(f) {
	if (f.nachname.value == "" || f.telefon.value == "") {
		if (f.nachname.value == "") {
			document.getElementById('nachname_err').style.visibility = "visible";
		}
		else {
			document.getElementById('nachname_err').style.visibility = "hidden";
		}
		if (f.telefon.value == "") {
			document.getElementById('telefon_err').style.visibility = "visible";
		}
		else {
			document.getElementById('telefon_err').style.visibility = "hidden";
		}
		return false
	}
	return true
}