Single post in Site Skins: How-To, and Helpful CSS

Hello! So a while back, E: someone Trico posted this code here to remove the fade in animation from the notification pop-up and I was wondering if there was a to do the same effect to the log out pop-up for when you click your pfp in the header? I tried doing it myself but none of the ways I tried worked so :| Honestly, if they can be combined into one code that'd be amazing but don't sweat it if it's not possible