Which inline html styles does GitHub markdown accept? [closed]

Question

This gives a pretty thorough description of how HTML elements are interpreted by markdown. But it does not discuss styles.

So far, the only thing I can get to work is image width.

1. I can't find a list anywhere of what is accepted/rendered
2. It appears that the style="....." attribute is completely ignored.
3. I can't even find a list of the old-fashioned style attributes (as opposed to the style attribute style=...)

https://gist.github.com/abalter/46df1b79e9f429342972477d7c20cebc

EDIT
Change span to div due to div being in the whitelisted tags per @waylan's comment under @chris's answer.

EDIT 2
It appears that firefox and chrome don't render any style attributes any more at all.

Answer 1

After GitHub converts Markdown to HTML,

The HTML is sanitized, aggressively removing things that could harm you and your kin—such as script tags, inline-styles, and class or id attributes. See the sanitization filter for the full whitelist.

You're right: style tags are not included in the whitelist. They are ignored.

The permitted attributes differ by tag. I recommend referring to the sanitization filter link above. It leads to a fairly readable Ruby source file.