function check_email(mail) { // funkcja sprawdzająca poprawność adresu e-mail
   invalid = " /:,;";
   for(i=0; i < invalid.length; i++) {
      bad = invalid.charAt(i);
      if (mail.indexOf (bad, 0) != -1) { return false }
   }
   at = mail.indexOf("@", 0);
   if( (at == -1) || (at == 0) ) { return false }
   if(mail.indexOf("@", at+1) != -1) { return false }
   period = mail.indexOf(".", at);
   if( (period == -1) || (period == at+1) ) { return false }
   if(period+3 > mail.length == -1) { return false }
   return true;
}

function Valid(pole){
var error = '0';
    
if (pole.name.value==""){ 
	document.getElementById("err1").className="error_view"; 
	error = '1';
}else { document.getElementById("err1").className="error_hidden"; }

if (pole.mail.value=="") {
error = '1';
document.getElementById("err2").className="error_view";
document.getElementById("err3").className="error_hidden";
}
else if(!(check_email(pole.mail.value))){ document.getElementById("err3").className="error_view"; document.getElementById("err2").className="error_hidden"; error = '1';}

if (pole.text.value==""){ 
	document.getElementById("err4").className="error_view"; 
	error = '1'; 
}else { document.getElementById("err4").className="error_hidden"; }

if (error == '1'){
	return false;
} else return true;
}

function onlydec(event,f)
{
if (event.srcElement) {kc = event.keyCode;} else {kc = event.which;}
if ((kc < 47 || kc > 57) && kc != 8 && kc != 0) return false;
return true;
}