function menu_chg(obj){
	for (i=1;i<=6;i++)
	{
		if (i!=obj){
			if (i==2){
        $('#pod_menu_'+i).hide();
        $('#menu_'+i).removeClass().addClass('top_menu_green');
			}else{
        $('#pod_menu_'+i).hide();
        $('#menu_'+i).removeClass().addClass('top_menu');
				
			}
		}
	}
  $('#pod_menu_'+obj).show();
  $('#menu_'+obj).removeClass().addClass('top_menu_blue');
}

	function getPageSize(){
		
			var xScroll, yScroll;
			
			if (window.innerHeight && window.scrollMaxY) {	
				xScroll = document.body.scrollWidth;
				yScroll = window.innerHeight + window.scrollMaxY;
			} else if (document.body.scrollHeight > document.body.offsetHeight){ // all but Explorer Mac
				xScroll = document.body.scrollWidth;
				yScroll = document.body.scrollHeight;
			} else { // Explorer Mac...would also work in Explorer 6 Strict, Mozilla and Safari
				xScroll = document.body.offsetWidth;
				yScroll = document.body.offsetHeight;
			}
			
			var windowWidth, windowHeight;
			if (self.innerHeight) {	// all except Explorer
				windowWidth = self.innerWidth;
				windowHeight = self.innerHeight;
			} else if (document.documentElement && document.documentElement.clientHeight) { // Explorer 6 Strict Mode
				windowWidth = document.documentElement.clientWidth;
				windowHeight = document.documentElement.clientHeight;
			} else if (document.body) { // other Explorers
				windowWidth = document.body.clientWidth;
				windowHeight = document.body.clientHeight;
			}	
			
			// for small pages with total height less then height of the viewport
			if(yScroll < windowHeight){
				pageHeight = windowHeight;
			} else { 
				pageHeight = yScroll;
			}
		
			// for small pages with total width less then width of the viewport
			if(xScroll < windowWidth){	
				pageWidth = windowWidth;
			} else {
				pageWidth = xScroll;
			}
		
		
			arrayPageSize = new Array(pageWidth,pageHeight,windowWidth,windowHeight) 
			return arrayPageSize;
			
		}
		
		function hideLightbox()
		{
			// get objects
			objOverlay = document.getElementById('overlay');
		
			// overlay
			objOverlay.style.display = 'none';
		}
		
  
    
		function tlo_szczegoly_foto(){
		
			var objBody = document.getElementsByTagName("body").item(0);
			
			// create overlay div and hardcode some functional styles (aesthetic styles are in CSS file)
			var objOverlay = document.createElement("div");
			objOverlay.setAttribute('id','overlay');
			//objOverlay.onclick = function () {hideLightbox(); return false;}
			objOverlay.style.display = 'none';
			objOverlay.style.position = 'absolute';
			objOverlay.style.top = '0';
			objOverlay.style.left = '0';
			objOverlay.style.zIndex = '90';
			objOverlay.style.width = '100%';
			objBody.insertBefore(objOverlay, objBody.firstChild);		
			var arrayPageSize = getPageSize();
			//var objOverlay = document.getElementById('overlay');
			objOverlay.style.height = (arrayPageSize[1] + 'px');
			objOverlay.style.display = 'block';
		}