How do I handle table margins when publishing to HTML5?

I have some documents with tables in FrameMaker 2019. The table styles have a left margin of 10mm.

When I publish to HTML5 it seems I have no options in Style Mapping dialogue for working with the margins/paddings of table styles.

I suppose I may be able to modify the stylesheet in css manually and attach it. But I would prefer handling this in the settings dialogue. Can it be done? Have I overlooked something?

/Bjørn