Post title color change if author online.

Hello!
Im wondering is there somecind of possibility to do this.
If author of the post is online then all his posts change the post title colour.

As i see it there is this possibility.
- Wordpress scan what users is online.
- Wordpress finds a post auther online.
- Wordpress finds all posts made by the author.
- Wordpress somehow instead of using normal CSS it uses a custom CSS for all post titles made by the online author.
You get it?
I cannot code but as i see it it should be easy for a php coder?