How to change Archlinux KDE 5 (Plasma) login theme?

Question

linux

Downloaded Splash themes - kde-look.org/content/show.php/Archlinux+KDE+KSplas...
The description says: Tested with KDE 4.11.x
I have Archlinux, DE: Plasma (KDE 5)
I found on the net that these themes are incompatible. You need to collect them somehow. Read on the forum - https://forum.kde.org/viewtopic.php?f=289&t=125293
For themes in KDE 4.x, the path is /usr/share/kde4/apps/theme/...
For Plasma - / usr/share/plasma/look-and-feel/...
Maybe there is a simpler theme conversion process or the package already exists?! I didn't find anything on the web!
PS: Who didn't understand what it is - "Splash Themes" is a splash screen for logging in after entering a username and password.