Can someone help me with something? I am not having any issues with themes or anything like that but I do want to know something

https://www.youtube.com/watch?v=-gyp...30q8dHyRy6Xrkg

In that link is a video of this dude showcasing this awesome look he pulled off and all i'm interested in is how the hell he did that animation for his windows opening, I have asked this in the comments but goddammit no one who watches that video speaks english cause the ****** who posted it also doesn't speak it, GODDAMMIT I DON'T SPEAK SPANISH! please someone tell me how he animated his stuff to open like that