FlatSquare

FlatSquare - it's a simple theme, performed in 16 colors from Google recommendations Material Design. Ideal for interfaces, placed in a flat square style.Installing:Instructions for Debian and Kubuntu (probably works for other distros too)Extract FlatSquare.tar.gzCopy folders to /home/.kde/share/apps/aurorae/themesThen go to System Settings>Workspace appearance and choose you favourite theme. Source: https://www.opendesktop.org/p/1002674