RML StyleSheets - Gambini/libRocket GitHub Wiki
RML Style Sheets
Styles can be included in an RML document in three ways: included from an external style sheet, declared in the header, or declared inline inside a specific tag.
External Style Sheets
Style sheets are included from an external source with the LINK tag. See Link Element.
Header Style Information
RCSS can be included directly inside the header, with the STYLE tag.
Inline Style Declaration
RCSS can be declared directly inside an element with the style attribute.