It can be done – although it would be severely frowned upon by the CSS purists

Can I ask for an example of what you want to do so I can suggest the best way to go?

I want to create a DIV with a responsive ad, the idea is to put it on the footer with a fixed position, so it will remain always visible on the botton of the mobile screen….

On my css theme i can do it… but on the unified… no idea of how to do it…

how to do it really isnt any different…  how did you do it just for tablets on the css only theme?  it should work similarly on unified…  though we use media rules for different screen sizes… 

Mr Papa said
how to do it really isnt any different…  how did you do it just for tablets on the css only theme?  it should work similarly on unified…  though we use media rules for different screen sizes… 

I´m not able of do it on the unified theme… I just did it on the ONLY CSS theme… so thats the reason why I´m Asking for help, if you read my first post you see that I don´t know how to to it on the unified theme, that is the theme that i´m using for tablet and mobile…

If you only use this theme on mobiles and tablets then your very first question – how to to do ONLY for mobiles and tablets – has no relevance. if you do not use this theme on a desktop there is no need to have rues that will ONLY apply for mobile use.

As to how you add CSS to the Unified theme then you do it in exactly the same way as the CSS only theme except the main styles file is called ‘unified.php’ not ‘unified.css’ and make sure your CSS is placed outside of php tags not inside them.

so if this new div goes in the footer I assume you mean the forum footer and not the page footer because if the latter then the code should be in your WP theme not the SP theme.

Not to be persnickety but if you read my first post, you see I asked how you did it…  Would have allowed showing how to do same for unified…