// JavaScript Document
function change_intro(whichIntro) {
	var intro_box = document.getElementById('intro_box');
	var intro_red = document.getElementById('intro_red');
	var intro_blue = document.getElementById('intro_blue');
	var intro_green = document.getElementById('intro_green');
	
	if(whichIntro == "blue")
	{
		intro_box.style.backgroundImage= "url('images/gd_intro_blue.png')";
		intro_red.style.display = 'none';
		intro_blue.style.display = 'block';
		intro_green.style.display = 'none';
	}
	else if(whichIntro == "green")
	{
		intro_box.style.backgroundImage= "url('images/gd_intro_green.png')";
		intro_red.style.display = 'none';
		intro_blue.style.display = 'none';
		intro_green.style.display = 'block';
	}
	else
	{
		intro_box.style.backgroundImage = "url('images/gd_intro_red.png')";
		intro_red.style.display = 'block';
		intro_blue.style.display = 'none';
		intro_green.style.display = 'none';
	}
}

var email_re = /^[\w-\.]+@[\w\.-]+[\.]{1}[\w]{2,3}$/;
function validate(form) {
  if(form.elements['txt_full_name'].value == '') {
	alert('Please indicate your name before proceeding.');
	form.elements['txt_full_name'].focus();
	return false;
  }
  if(form.elements['txt_email'].value == '' || !email_re.test(form.elements['txt_email'].value)) {
	alert('Please provide a valid email address before proceeding.');
	form.elements['txt_email'].focus();
	return false;
  }
  if(form.elements['ta_question'].value == '') {
	alert('Please indicate questions/comments before proceeding.');
	form.elements['ta_question'].focus();
	return false;
  }

  return true;
}