function MM_findObj(n, d) { //v4.01
var p,i,x;  if(!d) d=document; if((p=n.indexOf("?"))>0&&parent.frames.length) {
  d=parent.frames[n.substring(p+1)].document; n=n.substring(0,p);}
if(!(x=d[n])&&d.all) x=d.all[n]; for (i=0;!x&&i<d.forms.length;i++) x=d.forms[i][n];
for(i=0;!x&&d.layers&&i<d.layers.length;i++) x=MM_findObj(n,d.layers[i].document);
if(!x && d.getElementById) x=d.getElementById(n); return x;
}
var visible = 0;
function my_showHideLayers(id,v) {
var obj;
if ((obj=MM_findObj(id))!=null) { 
  if (obj.style) { obj=obj.style};
  if (v=='show') { visible = 1};
  if (v=='hide') { visible = 0};
  if (v=='toggle') { visible = ! visible};
  obj.visibility= visible?'visible':'hidden'; }
}