vlyMainOptions.getBtnDownload().addClickListener(new ClickListener() {

			@Override
			public void buttonClick(ClickEvent event) {
				// TODO Auto-generated method stub
				String url = "https://inscripciones.utm.edu.ec/consulta_certificado_ivento/";
//				String url = "https://app.utm.edu.ec/sga/";

						Window window = new Window("Certificados");
			            window.setWidth("800px");
			            window.setHeight("650px");
			            window.center();

			            BrowserFrame browserFrame = new BrowserFrame(null, new ExternalResource(url));
			            browserFrame.setWidth("100%");
			            browserFrame.setHeight("100%");

			            window.setContent(browserFrame);

			            UI.getCurrent().addWindow(window);
			}
		});