There is an option to create and use a CSS in both EasyHTML and EasyHTML/Help.
There is an option in the CONFIG to generate a style sheet from the basic styles in the document, like Heading 1 etc.
If you process with this option you will see a CSS file created in your web pages folder and the appropriate reference in the the HTML pages to use it.
If you turn on 'Generate and use Stylesheet' EasyHH will create simpler HTML, a link reference to a stylesheet and generate a basic stylesheet with the same name as your document.
If you use the 'ADNVANCED CONFIG.' options you can specify the name of the sytlesheet with the 'STYLE SHEET NAME' option
The stylesheet is always re-created when you process, if you don't want this to happen select 'Generate and Build Stylesheet' in the section for HTML Generation Options in the main CONFIG DIALOGUE and then go to the ADVANCED CONFIG DIALOGUE and select the function 'Overwritestylesheet' and set option to NO for which ever level you require.