Styles depending on URLs

[darkwinds]

Hello guys,
I've got a big problem.
The matter is that I want the styles to depend on URLs, for example:
www.style1.com = Style1
www.style2.com = Style2
I already got an URL-transmission, it works, but after you opened the site, there is the standard url. (www.style1.com = opening the site = www.transmissionURL.com/?styleid=1)
I want it that way, e.g.:
If you click on a thread, the url should be the same like in the beginning, and not change into the transmission URL.
Wrong: www.transmissionURL.com/announcement.php?f=3
Correct: www.style1.com/announcement.php?f=3

I hope I could explain what I wanted to say, because my English isn't that good .
Please help me,
yours sincerely