function ElOpacity(el, op)
{
var p ='';
if (typeof document.body.style.opacity == 'string') // CSS3 compliant (Moz 1.7+, Safari 1.2+, Opera 9)
{p = 'opacity';}
else if (typeof document.body.style.MozOpacity == 'string') // Mozilla 1.6 ט לכאהרו, Firefox 0.8 
{p = 'MozOpacity';}
else if (typeof document.body.style.KhtmlOpacity == 'string') // Konqueror 3.1, Safari 1.1
{p = 'KhtmlOpacity';}
else if (document.body.filters && navigator.appVersion.match(/MSIE ([\d.]+);/)[1]>=5.5) // Internet Exploder 5.5+
{p = 'filter';}
  
if (p=="filter")  
  {
   op *= 100;
   var oAlpha = el.filters['DXImageTransform.Microsoft.alpha'] || el.filters.alpha;
   if (oAlpha) oAlpha.opacity = op;
   else el.style.filter += "progid:DXImageTransform.Microsoft.Alpha(opacity="+op+")"; 
  }
else 
   el.style[p] = op;
}