https://gyazo.com/eb5c5741b6a9a16c692170a41a49c858.png
-

- 
-

- 
-

@rahaaatul
It appears not.
I tried to use CSS styles via Preview, but they're stripped off.
Plus the official statement from the
markup
repo (as seen below).Note
The HTML is sanitized, aggressively removing things that could harm you and your kinβsuch as script tags, inline-styles, and class or id attributes.
reference: https://github.com/github/markup