function checkNL(){
	var bOk=true;
	
	var email=document.getElementById('txtEmail');
		emailError=document.getElementById('txtEmailError');
	var number=document.getElementById('number');
		numberError=document.getElementById('numberError');
	var error = document.getElementById('grForm');   	
	
	// fields check
	var req = [email,number];
	for(i=0; i<req.length; i++) {
		if(req[i].value === '') {
			req[i].className = 'input_error';
			bOk = false;
		}
		else {
			req[i].className = 'input_txt';
		}
	}
	
	//email pattern
	var emailFilter = /^\w+([\.-]?\w+)*@\w+([\.-]?\w+)*(\.\w{2,3})+$/;
	if (!emailFilter.test(email.value)){			
		email.className = 'box_error';
		emailError.style.display = 'block';
		emailError.innerHTML = "Unesite validnu email adresu!";
		bOk = false;
		}
	else {
		emailError.innerHTML = "";
	}
	
	//number check
	if((number.value == "") || (number.value == 0)){
		number.className = 'box_error';
		numberError.style.display = 'block';
		numberError.innerHTML = "Captcha je obavezno polje!";
		bOk = false;
	}
	else {
		nameError.innerHTML = "";
	}
	
	// main form notification
	if(!bOk){
		error.style.display='';
	}
return bOk;
}