function getScreenWidth() {
		// based on http://www.howtocreate.co.uk/tutorials/index.php?tut=0&part=16
		if( typeof( window.innerWidth ) == 'number' ) 
			{
				return window.innerWidth;
		  };
		  
		return document.body.clientWidth;
		};
		
		function moveElementTo(strId,lngPx,lngPy){ 
		   // moves block element to pixel position
		  
			if (document.getElementById)		  
				{
				document.getElementById(strId).style.left = lngPx + "px"; 
			
				// strange bug in opera: doesn't accept px after top value
				if (navigator.userAgent.indexOf('pera') != -1)
					{ document.getElementById(strId).style.top  = lngPy; 
					}
				else
					{ document.getElementById(strId).style.top  = lngPy + "px"; 
					};
				};
			if (document.layers)					
				{
					document.layers[strId].left = lngPx;
					document.layers[strId].top = lngPy;					
				};	
			};		
		
		function getLeft(strObj){
			if (document.getElementById)
				{ return parseInt(document.getElementById(strObj).style.left) };
			if (document.layers)
				{ return (document.layers[strObj].left) }			
			};
			
		function getTop(strObj){
			if (document.getElementById)
				{ return parseInt(document.getElementById(strObj).style.top) };
			if (document.layers)
				{ return (document.layers[strObj].top) }			
			};
			
		function setStyleAttribute(strObjId,strAttrName,strAttrVal)
			{
			if (document.getElementById)
				{
				eval('document.getElementById(\''+strObjId+'\').style.'+strAttrName+'=\''+strAttrVal+'\'');
				};
			if (document.layers)
				{
				eval('document.layers[\''+strObjId+'\'].'+strAttrName+'=\''+strAttrVal+'\'');
				};
				
			};