function findStyleSheet(strName, frameRef) {//find predefined style sheets in the document
	//use for alteration in linked stylesheets
	var i=0,j=0;
	for(i=0; i < frameRef.document.styleSheets.length; i++) {
		for(j=0; j < frameRef.document.styleSheets[i].rules.length; j++) {
			if(frameRef.document.styleSheets[i].rules[j].selectorText==strName) return frameRef.document.styleSheets[i].rules[j];
		}
	}
	return null;
}