function StyleManager(){
	
	this.getRuleIndex = function(name){
      var cmpt = 0;
      var index = 0;
      var tab = null;
      var good = false;
      while(index<document.styleSheets.length && !good){
         tab = document.styleSheets[index].rules ? document.styleSheets[index].rules : document.styleSheets[index].cssRules;
         while(cmpt<tab.length && !good){
            if(tab[cmpt].selectorText.toLowerCase() == name)
               good = true;
            cmpt++;
         }
         index++;
      }
      return {sheetIndex:index-1,ruleIndex:cmpt-1};
   }
   
	this.changeRule = function(selector,cssText){
		infos = this.getRuleIndex(selector);  
		sheet = document.styleSheets[infos.sheetIndex];
		if(sheet.removeRule){
			sheet.removeRule(infos.ruleIndex);
		 	sheet.addRule(selector,cssText);         
		}
		else{
		 	sheet.deleteRule(infos.ruleIndex);
		 	sheet.insertRule(selector+"{"+cssText+"}", sheet.cssRules.length);
		}
	} 
	
	this.overrideRule = function(selector,cssText){
		infos = this.getRuleIndex(selector); 
		sheet = document.styleSheets[infos.sheetIndex];
		if(sheet.addRule){
		 	sheet.addRule(selector,cssText);         
		}
		else{
		 	sheet.insertRule(selector+"{"+cssText+"}", sheet.cssRules.length);
		}
	}
	
	this.correctPNG = function() 
   {
   for(var i=0; i<document.images.length; i++)
      {
	  var img = document.images[i]
	  var imgName = img.src.toUpperCase()
	  if (imgName.substring(imgName.length-3, imgName.length) == "PNG")
	     {
		 var imgID = (img.id) ? "id='" + img.id + "' " : ""
		 var imgClass = (img.className) ? "class='" + img.className + "' " : ""
		 var imgTitle = (img.title) ? "title='" + img.title + "' " : "title='" + img.alt + "' "
		 var imgStyle = "display:inline-block;" + img.style.cssText
		 if (img.align == "left") imgStyle = "float:left;" + imgStyle
		 if (img.align == "right") imgStyle = "float:right;" + imgStyle
		 if (img.parentElement.href) imgStyle = "cursor:hand;" + imgStyle
		 var strNewHTML = "<span " + imgID + imgClass + imgTitle
		 + " style=\"" + "width:" + img.width + "px; height:" + img.height + "px;" + imgStyle + ";"
	     + "filter:progid:DXImageTransform.Microsoft.AlphaImageLoader"
		 + "(src=\'" + img.src + "\', sizingMethod='scale');\"></span>"
		 img.outerHTML = strNewHTML
		 i = i-1
	     }
      }
   }
	
}