var nl=0;
var menuactivo="";

function ocultarmenu(){
   for(var pos=0;pos<7;pos++){
      document.getElementById('m'+pos).style.visibility='hidden';
   }
}
function am(){
  if (document.getElementById(menuactivo).filters){
  	 document.getElementById(menuactivo).runtimeStyle.filter="alpha(opacity=" + nl + ")";
	   switch(menuactivo){
	    case 'm0': document.getElementById("m6").runtimeStyle.filter="alpha(opacity=" + (nl+10) + ")"; break;
	   	case 'm3': document.getElementById("m5").runtimeStyle.filter="alpha(opacity=" + (nl+10) + ")"; break;
	   }
  }else{
    document.getElementById(menuactivo).style.opacity = (nl/100);
    document.getElementById(menuactivo).style.MozOpacity = (nl/100);  			  	
	   switch(menuactivo){
	    case 'm0': document.getElementById("m6").style.opacity = ((nl+10)/100);
	               document.getElementById("m6").style.MozOpacity = ((nl+10)/100); break;
	    			    
	   	case 'm3': document.getElementById("m5").style.opacity = ((nl+10)/100);
	   	           document.getElementById("m5").style.opacity = ((nl+10)/100); break;
	   }        
  }
}
function vermenu(menuitem){
   ocultarmenu();	
   menuactivo = menuitem;	
   document.getElementById(menuactivo).style.visibility='visible';
   switch(menuactivo){
    case 'm0': document.getElementById("m6").style.visibility='visible'; break;   	
   	case 'm3': document.getElementById("m5").style.visibility='visible'; break;
   }
   nl=80;
   am();
}