function centrar() {
    iz=(screen.width-document.body.clientWidth) / 2;
    de=(screen.height-document.body.clientHeight) / 2;
    moveTo(iz,de);
}

function popup_promocion(ruta){
  day = new Date();
  id = day.getTime();
  eval("page" + id + " = window.open(ruta, '" + id + "','scrollbars=0,toolbar=0,location=0,statusbar=0,menubar=0,resizable=0,width=550,height=300');");
}

var xOp7Up,xOp6Dn,xIE4Up,xIE4,xIE5,xNN4,xUA=navigator.userAgent.toLowerCase();if(window.opera){var i=xUA.indexOf('opera');if(i!=-1){var v=parseInt(xUA.charAt(i+6));xOp7Up=v>=7;xOp6Dn=v<7;}}else if(navigator.vendor!='KDE' && document.all && xUA.indexOf('msie')!=-1){xIE4Up=parseFloat(navigator.appVersion)>=4;xIE4=xUA.indexOf('msie 4')!=-1;xIE5=xUA.indexOf('msie 5')!=-1;}else if(document.layers){xNN4=true;}xMac=xUA.indexOf('mac')!=-1;function xDef(){for(var i=0; i<arguments.length; ++i){if(typeof(arguments[i])=='undefined') return false;}return true;}function xDisplay(e,s){if(!(e=xGetElementById(e))) return null;if(e.style && xDef(e.style.display)) {if (xStr(s)) e.style.display = s;return e.style.display;}return null;}function xGetElementById(e){if(typeof(e)!='string') return e;if(document.getElementById) e=document.getElementById(e);else if(document.all) e=document.all[e];else e=null;return e;}function xStr(s){for(var i=0; i<arguments.length; ++i){if(typeof(arguments[i])!='string') return false;}return true;}