Add default style for alternative login
Add default style for alternative login

Signed-off-by: Jochen <2adebb9ae67263bdef3d87f7c2531201909e0388@gmail.com>

andreas-p/nextcloud-server,nextcloud/server,nextcloud/server,nextcloud/server,andreas-p/nextcloud-server,nextcloud/server,andreas-p/nextcloud-server,andreas-p/nextcloud-server,andreas-p/nextcloud-server