Heading 7’s and Above in HTML, and the Auto Style Property

From time to time we're asked how to format a Heading 7, 8 or 9 for HTML or HTML Help.

HTML only allows for six levels of headings. This is a behavior of HTML (so is outside Author-its control). Although I'm not about to begin a philosophical discussion about the rights and wrongs of having more than 6 heading levels in an on-line document... that's something best left for another time and place.

Author-it uses the relevant Heading according to where the Topic appears in the structure of your Book - a topic at the first level will use the <H1> tag, second level the <H2> tag and so on. When a topic appears at the seventh (or higher) level, <H7> (or higher) tags are applied and this causes problems as they are not valid HTML tags.

What you want is to be able to define a specific style to be used by these Topics - and you can...

If you specify the style in the Document tab of the topic (instead of using [auto]) this style is also applied in the HTML. It does mean though, that the style selected is tied to that Topic - so if the topic is reused at a different level, it will have the "wrong" heading style. You could get around this by embedding the topic in an otherwise empty container topic (that uses the [auto] style property), or duplicating the topic.

The [auto] property means the Document Heading will be set to the styles "Heading 1", "Heading 2", "Heading 3", etc, as taken from the level of the Topic in the contents of the Book (apart from glossary terms which default to Heading 5). You can define a different style – but remember that this will impact on the reusability of a topic when it's used at different levels in various books.