// JavaScript Document

function toggleLayer( whichLayer, whichImage ){
  var elem, vis;
    if( document.getElementById ) // this is the way the standards work
	    elem = document.getElementById( whichLayer );
	else if( document.all ) // this is the way old msie versions work
		elem = document.all[whichLayer];
	else if( document.layers ) // this is the way nn4 works
		elem = document.layers[whichLayer];
		vis = elem.style; 
		// if the style.display value is blank we try to figure it out here
	if(vis.display==''&&elem.offsetWidth!=undefined&&elem.offsetHeight!=undefined)
		vis.display = (elem.offsetWidth!=0&&elem.offsetHeight!=0)?'block':'none';
		vis.display = (vis.display==''||vis.display=='block')?'none':'block';
	document['web_image'].src = whichImage; // Switch images on click
}