I’m pretty sure that it can’t be done. It’s a security thing. Think if someone created a website that was just one big giant iframe of your website, only changed the CSS to look a little different. Problematic.
Yeah, the security issue makes sense.
I’m quetioning cuz in my job we use an web based software to manage "bluetooth hotspots" . (Sounds Strange but it works)
This software have a (very poor) api, that works via http post and get functions, and reply only as a white page with all the response lines in a <pre> tag. So i did a little test ( only to show for my boss that the API sucks) creating a page with form that targets itself, and echo the values inputed into the src of a iframe, so it loads those ugly logs without changing the page.
My intent was only make the iframe black* and the characters green. (Console-like got it?)
* got the black iframe setting allowtransparency="true" and putting it into a blck <div>, but the font color was black to, sice is the default color on <pre> tags. :(