function changeBackground(el,num){
doSelect(num);
	document.getElementById('bg').style.backgroundImage = 'url(images/ecard/background/ecard'+num+'.jpg)';
	document.forms[0].card.value = num;
}

function changeSeal(num){
	doSeal(num);
	document.forms[0].seal.value = num;
}

function doSelect(num){
	var i=1;
	while (i<6) {
		document.getElementById(i+'').style.backgroundImage = '';
		i++;
	}
	document.getElementById(num).style.backgroundImage = 'url(images/ecard/icon/selected.png)';
	document.getElementById(num).style.backgroundRepeat = 'repeat';
}

function doSeal(num){
	var i=1;
	while (i<6) {
		document.getElementById('seal'+i).style.backgroundImage = '';
		i++;
	}
	document.getElementById('seal'+num).style.backgroundImage = 'url(images/ecard/icon/selected.png)';
	document.getElementById('seal'+num).style.backgroundRepeat = '';
}

function checkMail(){
	var remail = document.getElementById("remail");
	var semail = document.getElementById("semail");

	var regem = new RegExp(/^[a-z0-9._%+-]+@[A-Za-z0-9.-]+\.[a-z]{2,4}$/);
	if (!remail.value.match(regem)){
		alert("email is not valid, please check them again");
		remail.focus();
		return false;
	}
	if (!semail.value.match(regem)){
		alert("email is not valid, please check them again");
		semail.focus();
		return false;
	}
	if(remail.value.length==0){
		alert("please, type in email field");
		remail.focus();
		return false;
	}
	if(semail.value.length==0){
		alert("please, type in email field");
		semail.focus();
		return false;
	}
	return true;

}