var foco_ti=0;
var foco_os=new Array();
var foco_n=0;
function foco_nuevo(o,f)
{this.o=o
 this.f=f
 return this
}
function foco_haza(o,f){
var i
for(i=0;i<foco_n;i++)if(foco_os[i].o==o)break
if(i==foco_n){
 foco_os[foco_n++]=new foco_nuevo(o,f)
 if(foco_n==1)foco_ti=setInterval("foco_rutina()",80)
}else
 foco_os[i].f=f;
}
function foco_haz(o,i,f){
foco_pon(o,i)
foco_haza(o,f)
}
function foco_pon(o,q){
var i
for(i=0;i<foco_n;i++)if(foco_os[i].o==o)break
if(i<foco_n){
 while(++i<foco_n)foco_os[i-1]=foco_os[i]
 foco_n--
}
if(foco_n==0)clearInterval(foco_ti)
if (o.style&&o.style.MozOpacity)
o.style.MozOpacity=q/100
else if (o.filters)
o.filters.alpha.opacity=q
}
function foco_rutina(){
var i,o,f,fin
for(i=0;i<foco_n;i++){
o=foco_os[i].o
fin=0

if (o.style&&o.style.MozOpacity)
 f=100*o.style.MozOpacity
else if (o.filters)
 f=o.filters.alpha.opacity

if(f<foco_os[i].f){
 f+=10
 if(f>=foco_os[i].f){f=foco_os[i].f;fin=1}
}else{
 f-=10
 if(f<=foco_os[i].f){f=foco_os[i].f;fin=1}
}

if (o.style&&o.style.MozOpacity)
 o.style.MozOpacity=f/100
else if (o.filters)
 o.filters.alpha.opacity=f

 if(fin){
   if(--foco_n>i)foco_os[i--]=foco_os[foco_n]
   if(foco_n==0)clearInterval(foco_ti)
 }
}
}