function sentered(urel, sizex, sizey){
 var posx = (screen.width / 2) - (sizex / 2);
 var posy = (screen.height / 2) - (sizey / 2);
 window.open(urel, 'okno', 'toolbar=no,location=no,directories=no,status=no,menubar=no,scrollbars=yes,resizable=no,copyhistory=no,width=' + sizex + ',height=' + sizey + ',left=' + posx + ',top=' + posy);
 return false;
}

function sentered_name(urel, sizex, sizey, nm){
 var posx = (screen.width / 2) - (sizex / 2);
 var posy = (screen.height / 2) - (sizey / 2);
 window.open(urel, nm, 'toolbar=no,location=no,directories=no,status=no,menubar=no,scrollbars=yes,resizable=no,copyhistory=no,width=' + sizex + ',height=' + sizey + ',left=' + posx + ',top=' + posy);
 return false;
}

function sentered_noscroll(urel, sizex, sizey){
 var posx = (screen.width / 2) - (sizex / 2);
 var posy = (screen.height / 2) - (sizey / 2);
 window.open(urel, 'okno', 'toolbar=no,location=no,directories=no,status=no,menubar=no,scrollbars=no,resizable=no,copyhistory=no,width=' + sizex + ',height=' + sizey + ',left=' + posx + ',top=' + posy);
 return false;
}

function MM_swapImgRestore() { //v3.0
  var i,x,a=document.MM_sr; for(i=0;a&&i<a.length&&(x=a[i])&&x.oSrc;i++) x.src=x.oSrc;
}

function MM_preloadImages() { //v3.0
  var d=document; if(d.images){ if(!d.MM_p) d.MM_p=new Array();
    var i,j=d.MM_p.length,a=MM_preloadImages.arguments; for(i=0; i<a.length; i++)
    if (a[i].indexOf("#")!=0){ d.MM_p[j]=new Image; d.MM_p[j++].src=a[i];}}
}

function MM_findObj(n, d) { //v4.0
  var p,i,x;  if(!d) d=document; if((p=n.indexOf("?"))>0&&parent.frames.length) {
    d=parent.frames[n.substring(p+1)].document; n=n.substring(0,p);}
  if(!(x=d[n])&&d.all) x=d.all[n]; for (i=0;!x&&i<d.forms.length;i++) x=d.forms[i][n];
  for(i=0;!x&&d.layers&&i<d.layers.length;i++) x=MM_findObj(n,d.layers[i].document);
  if(!x && document.getElementById) x=document.getElementById(n); return x;
}

function MM_swapImage() { //v3.0
  var i,j=0,x,a=MM_swapImage.arguments; document.MM_sr=new Array; for(i=0;i<(a.length-2);i+=3)
   if ((x=MM_findObj(a[i]))!=null){document.MM_sr[j++]=x; if(!x.oSrc) x.oSrc=x.src; x.src=a[i+2];}
}

function is_email(email) {
  var emailPattern = /^[a-z0-9]+([_|-|.][a-z0-9]+)*\@([a-z0-9]+((-*)(.*)[a-z0-9]+)*\.(com|edu|biz|org|gov|int|info|mil|net|arpa|name|museum|coop|aero|[a-z][a-z])|(\[\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}\]))$/;                     
  return emailPattern.test(email.toLowerCase());
}

function sprawdz_email(pole) {
  if (!is_email(pole.value)) {
    alert('Podany e-mail jest niepoprawny.');
    pole.focus();
    pole.select();
	return false;
  }
  return true;
}

function sprawdz_email_en(pole) {
  if (!is_email(pole.value)) {
    alert("Entered e-mail is not correct.");
    pole.focus();
    pole.select();
	return false;
  }
  return true;
}

function powieksz(strToUrl,name)
{
 window.open(strToUrl, name,'toolbar=no,location=no,directories=no,status=no,menubar=no,scrollbars=no,resizable=no,copyhistory=no,width=200,height=200');
 return false;
}