Did you set your browser zoom to 100% (default)? If not, do that. Your CSS looks fine. I know someone else had this error because their browser was zoomed in at 110%.
It might be easier to sort out if you all (@nickvyh, @dhairyakhale, @amitwe) create your own topics and mention me @jibblyj so I can help you with this individually. It’s better to do this than to spam a single thread.