var color = '#bdbdbd';
var ercolor = '#414141';

function pruefe() {
	var senden = true;

	var name = document.getElementById("name").value;
	var email = document.getElementById("email").value;
	var betreff = document.getElementById("betreff").value;
	var message = document.getElementById("message").value;
	
	if(name == "") {
		document.getElementById("name").style.backgroundColor=ercolor;
		senden = false;
	} else {
		document.getElementById("name").style.backgroundColor=color;
	}

	if(email == "") {
		document.getElementById("email").style.backgroundColor=ercolor;
		senden = false;
	} else if (email.indexOf("@") == -1) {
		document.getElementById("email").style.backgroundColor=ercolor;
		senden = false;
	} else if (email.indexOf(".") == -1) {
		document.getElementById("email").style.backgroundColor=ercolor;
		senden = false;
	} else {
		document.getElementById("email").style.backgroundColor=color;
	}

	if(betreff == "") {
		document.getElementById("betreff").style.backgroundColor=ercolor;
		senden = false;
	} else {
		document.getElementById("betreff").style.backgroundColor=color;
	}

	if(message == "") {
		document.getElementById("message").style.backgroundColor=ercolor;
		senden = false;
	} else {
		document.getElementById("message").style.backgroundColor=color;
	}

	return senden;
}

function normalisieren() {
	document.getElementById("name").style.backgroundColor=color;
	document.getElementById("email").style.backgroundColor=color;
	document.getElementById("betreff").style.backgroundColor=color;
	document.getElementById("message").style.backgroundColor=color;
	return true;
}