function categoria ( id ) {
	var categoria = new YAHOO.util.Element('categoria-' + id);
	
	categoria.on('click', function () {				
		for ( var i = 0; i <= arr_categoria.length; i++ ) {
			if ( YAHOO.util.Dom.getStyle(document.getElementById('sottocategoria-' + arr_categoria[i]), 'display') != 'none' ) {
				YAHOO.util.Dom.setStyle(document.getElementById('categoria-' + arr_categoria[i]), 'listStyleImage', 'url(/images/common/plus-icon.png)');
				
				var anim = new YAHOO.util.Anim('sottocategoria-' + arr_categoria[i]);
				anim.attributes.opacity = { from: 1, to: .2 }; 
				anim.duration = 0.2; 
				anim.method = YAHOO.util.Easing.easeOutStrong; 
				anim.animate();
				
				anim.onComplete.subscribe(function() {
					var sHeight = YAHOO.util.Dom.getRegion(document.getElementById('sottocategoria-' + arr_categoria[i])).bottom - YAHOO.util.Dom.getRegion(document.getElementById('sottocategoria-' + arr_categoria[i])).top;
					var anim = new YAHOO.util.Anim('sottocategoria-' + arr_categoria[i]);
					anim.attributes.height = { to: 0 };
					anim.attributes.opacity = { from: 0.2, to: 0 }; 
					anim.duration = 0.5; 
					anim.method = YAHOO.util.Easing.easeOutStrong;
					anim.animate();
					
					anim.onComplete.subscribe(function() {
						YAHOO.util.Dom.setStyle(document.getElementById('sottocategoria-' + arr_categoria[i]), 'height', sHeight.toString() + 'px');
						YAHOO.util.Dom.setStyle(document.getElementById('sottocategoria-' + arr_categoria[i]), 'display', 'none');
					});
				});
				break;
			}
		}
	
		if ( YAHOO.util.Dom.getStyle(document.getElementById('sottocategoria-' + id), 'display') == 'none') {
			YAHOO.util.Dom.setStyle(document.getElementById('categoria-' + id), 'listStyleImage', 'url(/images/common/minus-icon.png)');
			
			YAHOO.util.Dom.setStyle(document.getElementById('sottocategoria-' + id), 'opacity', 0);
			YAHOO.util.Dom.setStyle(document.getElementById('sottocategoria-' + id), 'position', 'absolute');
			YAHOO.util.Dom.setStyle(document.getElementById('sottocategoria-' + id), 'display', 'block');
			var sHeight = YAHOO.util.Dom.getRegion(document.getElementById('sottocategoria-' + id)).bottom - YAHOO.util.Dom.getRegion(document.getElementById('sottocategoria-' + id)).top;
			YAHOO.util.Dom.setStyle(document.getElementById('sottocategoria-' + id), 'display', 'none');
			YAHOO.util.Dom.setStyle(document.getElementById('sottocategoria-' + id), 'position', 'static');
			YAHOO.util.Dom.setStyle(document.getElementById('sottocategoria-' + id), 'height', '0px');
			YAHOO.util.Dom.setStyle(document.getElementById('sottocategoria-' + id), 'display', 'block');
			
// 			var anim = new YAHOO.util.Anim('sottocategoria-' + id)
// 			anim.attributes.opacity = { from: 0, to: .2 };
// 			anim.duration = .3;
// 			anim.method = YAHOO.util.Easing.easeOutStrong; 
// 			anim.animate();
// 			anim.onComplete.subscribe(function() {
				var anim = new YAHOO.util.Anim('sottocategoria-' + id);
				anim.attributes.height = { from: 0, to: sHeight }; 
				anim.attributes.opacity = { from: 0, to: 1 }; 
				anim.duration = 0.7; 
				anim.method = YAHOO.util.Easing.easeOutStrong; 
				anim.animate();				
// 			});
		}
	});
}