//global variables

	var currentDescLyrNo// initial current description layer
	
	// toggle tab description layers
	function toggleDescriptionLyr(inputLyrNo) {
		
		var count, lyrRef, visibility
		//alert(screen.availHeight +' ,w: '+screen.availWidth);	
		var	spaceLeft = (screen.availWidth - 735) / 2;
		var newLeft = 95 + parseInt(spaceLeft) - 10;
			
		for (count=0;count<9;count++) {
				if (count == inputLyrNo) {

					visibility = "visible";
					currentDescLyrNo = inputLyrNo; //store current selected layer
				}
				else {
					visibility = "hidden";
				}

				//change layer visibility
				if (document.layers) {
					lyrRef = eval("document.layers['id" + count + "'];");
					lyrRef.visibility = visibility;				
					lyrRef.left = newLeft; 
				}
				else if (document.all || document.getElementById) {					
					lyrRef = eval("document.getElementById('id" + count + "');");
					lyrRef.style.visibility = visibility;
					lyrRef.style.left = newLeft;
				}
		}
	}
	
	
	function hideAll() {
		
		var count, lyrRef
		
		for (count=0;count<9;count++) {
				//change layer visibility
				if (document.layers) {
					lyrRef = eval("document.layers['id" + count + "'];");
					lyrRef.visibility = "hide";
				}
				else if (document.all || document.getElementById) {
					lyrRef = eval("document.getElementById('id"+count +"');");
					lyrRef.style.visibility = "hidden";
				}
		}
	}