Live and Design view look great but uploaded page does not display correctly!

I did not build this website and the company that did is gone. I needed to put a banner on my main page and had to create a new style to format it. Browser previws on my PC - Chrome, Firefox, IE, and Edge all look great my PC but when uploaded to my website it does not display correctly. The text is there but not the formatting. I uploaded both the edited page and the edited CSS, but it seems like the live site is not reading the CSS.

I can make changes in Dreamweaver and they show up right away on my PC so I am not sure what I am doing wrong. It's probably someting stupid but it is really throwing me that the local view is good but the published view is not. Any help appreciated!