SDDM is a Login Manager for Linux which can be themed by qml. This theme is designed for archlinux users.
This theme has been modifed from https://github.com/absturztaube/sddm-archlinux-theme to have dark inputs and removes the border around the edges of the screen.
- copy the folder archlinuxdark to /usr/share/sddm/themes/
- change CurrentTheme to archlinuxdark in /etc/sddm.conf
- enjoy