function ChStyle(el1,el2){
				el1.style.borderLeft = "15px solid "+CSScolor1;
				el1.style.background = CSScolor3;		 		
				document.getElementById(el2).style.background = CSScolor2;  
	}
	
	function RmStyle(el1,el2){
			
				el1.style.borderLeft = "0px #FFF" // solid "+CSScolor1;
				el1.style.background = "#FFF" ; //CSScolor3;		 		
				document.getElementById(el2).style.background = "#FFF" ;//CSScolor2;  
	}
	function CheckForm(){
		
		var msg = "";
		var drap = 0 ;
		document.getElementById('contact_error').innerHTML = "" ;
		var element_label="",value_label="" ;
		var nb = document.getElementsByTagName("label").length-1 ;
		for ( var i=0; i<nb; i++ ) {	 
				
				element_label = document.getElementsByTagName("label")[i];
				value_label   = document.getElementsByTagName("input")[i].id;			 
				RmStyle(element_label,value_label);
		}
	
		for ( var i=0; i<nb; i++ ) {
			
			element_label = document.getElementsByTagName("label")[i];
			value_label   = document.getElementsByTagName("input")[i].id;
	
			if( document.getElementById(value_label).value == "" ){
			
				msg +=  element_label.firstChild.nodeValue +", " ;
				ChStyle(element_label,value_label);		 
		
				if(drap == 0 ){
					document.getElementById(value_label).focus();
					drap++;
				}
			}
		
		}		
	
		if(msg.length > 0 ){

				txt = avertiss + "<br/> " ;
				txt += msg; 				
				document.getElementById('contact_error').innerHTML = txt ;
				return false ;	
		}
		else	if(document.getElementById('mail').value.indexOf('@') <= 0  ){		 
	
				element_label = document.getElementsByTagName("label")[3];
				value_label   = document.getElementsByTagName("input")[3].id; 
				ChStyle(element_label,value_label);
				document.getElementById('contact_error').innerHTML = msgmail ;
				 document.getElementById(value_label).focus();
				return false ;	
		}
 		else
			document.form_contact.submit();
 
	
}