function flagForm(element){
	document.getElementById(element).className = 'highlight';
	document.getElementById(element).onblur = new Function("flagFormRestore('" + element + "')");
	document.getElementById(element).focus();
}

function flagFormRestore(element){
	document.getElementById(element).className = "";
}

function validateVolunteerForm() {

	if (document.getElementById('yourname').value == ""){
		alert('You did not enter your name.');
		flagForm('yourname');
		return false;
	} else if (document.getElementById('email').value == ""){
		alert('You did not enter your email address.');
		flagForm('email');
		return false;
	} else if (document.getElementById('phone').value == ""){
		alert('You did not enter your phone number.');
		flagForm('phone');
		return false;
	} else if (document.getElementById('location').value == ""){
		alert('You did not enter your nearest town or city.');
		flagForm('location');
		return false;
	}
	
	return true;

}