A client has an older static HTML site which I would like to port over to WordPress, but I have been informed that this can be very time consuming re 50 pages.

I have FTP access for various reasons because the owner cannot get the login details for me, and have found that there is no *style.css* files/folders even though I see CSS styling in the code on each page. How would I go about changing the CSS style for just the home page so I can give the page a more up to date look? Directly via the CSS styling code on the page?