function check_email_field() {
	var email = document.getElementById('subscribe_to_mailing_list').value;
	var emailPattern = /^[a-zA-Z0-9._-]+@[a-zA-Z0-9.-]+\.[a-zA-Z]{2,4}$/;
	if ((email == '') || (email == 'Insert Email Here') || (!emailPattern.test(email))) {
		alert('Please enter a valid email address.');
		return false;
	}
	window.open('http://www.imacservices.com/subscribeus.php?email=' + email,'mailing_list','width=700,height=550,toolbar=0,resizable=1');
	return false;
}
// opens new window showing US map with locations of reps;
function show_map() {
	window.open('http://www.imacservices.com/includes/flyouts/map/us_map.html','locations_map','height=520,width=620,toolbar=no,directories=no,status=no,menubar=no,scrollbars=no,resizable=no');
	return false;
}
function email_focus(a,b) {
	if (a) {
		if (document.getElementById('subscribe_to_mailing_list').value == 'Insert Email Here') {
			document.getElementById('subscribe_to_mailing_list').value = '';
		}
	}
	else {
		if (b) {
			document.getElementById('subscribe_to_mailing_list').style.color = '#000000';
		}
		else {
			if (document.getElementById('subscribe_to_mailing_list').value == '') {
				document.getElementById('subscribe_to_mailing_list').style.color = '#aaaaaa';
				document.getElementById('subscribe_to_mailing_list').value = 'Insert Email Here';
			}
		}
	}
}
function play_button_rollover(a) {
	if (a) {
		document.getElementById('play_button_off').style.display = 'block';
		document.getElementById('play_button_on').style.display = 'none';
	}
	else {
		document.getElementById('play_button_off').style.display = 'none';
		document.getElementById('play_button_on').style.display = 'block';
	}
}

/*
 * Font increase/descrease;
 */
function changeFontSize(element,step) {
	step = parseInt(step,10);
	var el = document.getElementById(element);
	var curFont = parseInt(el.style.fontSize,10);
	el.style.fontSize = (curFont+step) + 'px';
	return;
}