Dynamic page parts in RefineryCMS

show.html.erb

<% left_col_content = @page.content_for(:left_column) %>
<% content_content = @page.content_for(:content) %>
<% right_col_content = @page.content_for(:right_column) %>
<% if (!left_col_content && !!content_content && !right_col_content) -%>
	<%= render :partial => 'content', 	:object => @page,
																			:locals => {  :css => "grid_12 alpha omega" } %>
<% end -%>

<% if (!!left_col_content && !!content_content && !right_col_content) -%>
	<%= render :partial => 'leftcol', 	:object => @page,
																			:locals => { 	:css => "grid_2 alpha" } %>
	<%= render :partial => 'content', 	:object => @page,
																			:locals => { 	:css => "grid_10 omega" } %>
<% end -%>

<% if (!left_col_content && !!content_content && !!right_col_content) -%>
	<%= render :partial => 'content', 	:object => @page,
																			:locals => { 	:css => "grid_8 alpha" } %>
	<%= render :partial => 'rightcol', 	:object => @page,
																			:locals => { 	:css => "grid_4 omega" } %>
<% end -%>

<% if (!!left_col_content && !!content_content && !!right_col_content) -%>
	<%= render :partial => 'leftcol', 	:object => @page,
																			:locals => { 	:css => "grid_2 alpha" } %>
	<%= render :partial => 'content', 	:object => @page,
	 																		:locals => { 	:css => "grid_6"} %>
	<%= render :partial => 'rightcol', 	:object => @page,
																			:locals => { 	:css => "grid_4 omega" } %>
<% end -%>