This test page
To apply RDDL resources to inline elements, just wrap the rddl:resource element around them.
Apply RDDL to an entire section requires an “out of line” RDDL resource. (Allowing rddl:resource elements to wrap sections would interrupt the structure of the document more than I'm willing to allow.)
Put an empty rddl:resource element in the head of your webpage.
Assign an ID value to the rddl:resource.
Refer to the ID of the rddl:resource with the rddl attribute on section.
The stylesheets will wrap the rddl:resource around the section in the resulting HTML.