Doc-To-Help 2007 provides and uses cascading style sheets (CSS) for HTML documents in much the same way it provides and uses Word templates for Word documents. Predefined or customized Word templates are attached to Word source documents and help targets to be used by Doc-To-Help to determine the formatting and styles of your help files. Similarly, for HTML documents, Doc-To-Help uses style sheets attached to HTML source documents and help targets.
The style sheet attached to your HTML source documents is determined by the HTMLDefaultCSS property under Project Settings, which is set by default when you create a project. You may also choose to add and attach your own cascading style sheet. Once a style sheet is attached, you can edit your source documents using the existing styles or, if necessary, create new styles in the style sheet. See Source Document Style Sheets for more information.
Use the StyleSheet property of each help target to determine the style sheet that is attached to every HTML document in your help file, defining the appearance of the target. See Help Target Style Sheets for more information.
All style sheets and Word templates available within a project are listed in the right-hand pane of the project editor when the Project icon is clicked and the Templates node is selected. New style sheets can also be easily added later.
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Source Document Style Sheets