Hello, I didn't see these problems on my version of Opera. Have you maybe checked this on a second machine? Opera unfortunately, does not meet a lot of W3C standards and different version consistently do not display css correctly. Unfortuntely, Opera has become an "almost working" browser for most developers and most treat web development this way when it comes to this browser because it ignore correct css styling. All that to say
I would say first check it on a second machine.