function isEmail(str) {
  var r1 = new RegExp("(@.*@)|(\\.\\.)|(@\\.)|(^\\.)");
  var r2 = new RegExp("^.+\\@(\\[?)[a-zA-Z0-9\\-\\.]+\\.([a-zA-Z]{2,3}|[0-9]{1,3})(\\]?)$");
  return (!r1.test(str) && r2.test(str));
	}

function chk(){
	if(document.getElementById("cardnum").value==''){
		alert('Please fill in your card number');
		document.getElementById('cardnum').style.background='#C2C2FE';
		document.getElementById("cardnum").focus();
		return false;
	}
	if(document.getElementById("name").value==''){
		alert('Please fill in your First Name');
		document.getElementById("name").focus();
		document.getElementById("fname").style.color='#FF0000';
		return false;
	}else{document.getElementById("fname").style.color='#000000';}
	if(document.getElementById("name2").value==''){
		alert('Please fill in your Last Name');
		document.getElementById("name2").focus();
		document.getElementById("lname").style.color='#FF0000';
		return false;
	}else{document.getElementById("lname").style.color='#000000';}
	if(document.getElementById("address").value==''){
		alert('Please fill in your address');
		document.getElementById("address").focus();
		document.getElementById("tdaddress").style.color='#FF0000';
		return false;
	}else{document.getElementById("tdaddress").style.color='#000000';}
	if(document.getElementById("city").value==''){
		alert('Please fill in your city');
		document.getElementById("city").focus();
		document.getElementById("tdcity").style.color='#FF0000';
		return false;
	}else{document.getElementById("tdcity").style.color='#000000';}
	if(document.getElementById("state").value==''){
		alert('Please select your state');
		document.getElementById("state").focus();
		document.getElementById("tdstate").style.color='#FF0000';
		return false;
	}else{document.getElementById("tdstate").style.color='#000000';}
	if(document.getElementById("postcode").value==''){
		alert('Please enter your postcode');
		document.getElementById("postcode").focus();
		document.getElementById("tdzip").style.color='#FF0000';
		return false;
	}else{document.getElementById("tdzip").style.color='#000000';}
	if(document.getElementById("phone").value==''){
		alert('Please enter your phone');
		document.getElementById("phone").focus();
		document.getElementById("tdphone").style.color='#FF0000';
		return false;
	}else{document.getElementById("tdphone").style.color='#000000';}
	if(document.getElementById("email").value==''){
		document.getElementById("email").focus();
		document.getElementById("tdemail").style.color='#FF0000';
		alert('Please enter your email');
		return false;
	}else{document.getElementById("tdemail").style.color='#000000';}
  if (!isEmail(document.getElementById("email").value)) {
	alert('Email address format is incorrect');
	document.getElementById("email").select();
		document.getElementById("tdemail").style.color='#FF0000';
    return false;
	}else{document.getElementById("tdemail").style.color='#000000';}
}