Hello Sammy,
You can eventually add custom style or property for the style into class attribute of body tag in template that is used as basic template for pages in PortalEngine.
You can change the default class in the
~\CMSPages\PortalTemplate.aspx property for the style into class attribute of body tag in template that is used as basic template for pages in PortalEngine. You can add to the body parameter your macro, e.g.:
<body class="<%=BodyClass%> <%=MyClass %> " <%=BodyParameters%>>
And then, in the code behind of the page, you can use your decision logic and fill the MyClass macro (property) with appropriate classname.
Also, the body tag class property can be obtained from context:
CMSContext.CurrentBodyClassBest regards,
Martin Danko