Plain p:panel without CSS
p:panel with styleClass: jeesl-tree

Tree

The panel containing the tree element must have the class jeesl-tree applied for the responsive css to display.

A tree node can be visually marked as disabled by adding the class jeesl-disabled to the respective node (see line 3 in the code sample - in this case depending on the node's visible property).

			<p:panel header="Plain p:panel without CSS">
        		<p:tree var="node" value="#{stylePanelTreeBean.root}">
		        <p:treeNode styleClass="#{not node.get('visible') ? 'jeesl-disabled' : ''}">
		            <h:outputText value="#{node.get('name')}" />
		        </p:treeNode>
				</p:tree>
			</p:panel>
       		<p:panel header="p:panel with styleClass: jeesl-tree" styleClass="jeesl-tree">
				<p:tree var="node" value="#{stylePanelTreeBean.root}">
			        <p:treeNode styleClass="#{not node.get('visible') ? 'jeesl-disabled' : ''}">
			            <h:outputText value="#{node.get('name')}" />
			        </p:treeNode>
			    </p:tree>
			</p:panel>