var menu_items=new Array(
  "domu",
	"o_nas",
	"materialy",
	"odkazy",
	"reference",
	"kontakt"
);



function over_menu(id_btn,pushed){
  if (pushed){
    for (i=0;i<menu_items.length;i++){
      if (document.getElementById('btn_'+menu_items[i])){
        document.getElementById('btn_'+menu_items[i]).style.visibility='visible';
        document.getElementById('btn_'+menu_items[i]+'_p').style.visibility='hidden';
      }
    }
    document.getElementById('btn_'+id_btn+'_p').style.visibility='visible';
  }else{
    document.getElementById('btn_'+id_btn).style.visibility='visible'; 
    document.getElementById('btn_'+id_btn+'_p').style.visibility='hidden';
  }
}

function over(obr,new_obr){ obr.src=new_obr; }