function validace(){
	with (document.getElementById('formular')) {
		if ( !NotEmpty(jmeno,"name and surname",true)) return(false)
		if ( !IsEmail(em, true)) return(false)
	//	if ( !NotEmpty(tel,"phone",true)) return(false)
		if ( !NotEmpty(vzkaz,"message",true)) return(false)
		}
	}
	function aktivuj_box(box) {
		box.style.border="1px solid #746C47";
	 	box.style.backgroundColor="#FAF8F1";
	}
	function deaktivuj_box(box) {
		box.style.border="1px solid #C5BE9C";
		box.style.backgroundColor="#FFFFFF";
	}

	function Trim( cInput ) {
	   var cStr="";
	   var nLength,i;
	   var nFirst,nLast;
	   
	   if( typeof(cInput)=="string" ) {
	       nLength=cInput.length;
	       nFirst=0;
	       while( cInput.charCodeAt(nFirst)<33 && nFirst<nLength ) nFirst++;
	       cStr=cInput.substr(nFirst,nLength);
	       nLast=cStr.length-1;
	       while( cStr.charCodeAt(nLast)<33 && nLast>0 ) nLast--; 
	       cStr=cStr.substr(0,nLast+1);
	   }
	   
	   return cStr; 
	} 
	function NotEmpty( inputVal, sMessage, bSelect ) {
	   var bRet = false;
	   var cVal;
	   
	   if( typeof(inputVal.value)=="string" ) {
	       cVal=Trim(inputVal.value);
	       if( cVal.length>0 )
	           bRet=true;                        
	   }
	       
	   if( !bRet && bSelect) {
	       alert( "Insert "+ sMessage +"." );
	       inputVal.select();        
	       inputVal.focus();
	
	   }
	   
	   return bRet;
	}


	function IsEmail( inputVal, bSelect ) {
	  var exclude=/[^@\-\.\w]|^[_@\.\-]|[\._\-]{2}|[@\.]{2}|(@)[^@]*\1/;
	  var check=/@[\w\-]+\./;
	  var checkend=/\.[a-zA-Z]{2,3}$/;
	  var emailad=inputVal.value.trim();
	
	  inputVal.value=emailad;
	  
		if(((emailad.search(exclude) != -1)||(emailad.search(check)) == -1)||(emailad.search(checkend) == -1)){
			 alert("Please, insert correct email adress.");
	     if( bSelect ) { 
	         inputVal.select();        
	         inputVal.focus();
	     }    
	     return false;
		}
	  return true;
	}

	String.prototype.trim = function()
	{
	    return this.replace(/(^\s*)|(\s*$)/g, "");
	}