A minimal dark configuration for the XLogin prompt.
Back up your /etc/X11/xdm/Xresources and replace it with the following.
This example uses the snap bitmap font from fonts/artwiz-font, but you can replace it with whatever compels you most.
xlogin.Login.greeting: X Display Manager
xlogin.Login.fail: wrong guess.
xlogin.Login.changePasswdMessage: change.
xlogin.Login.namePrompt: username:
xlogin.Login.passwdPrompt: password:
xlogin.Login.echoPasswd: true
xlogin.Login.background: #121212
xlogin.Login.foreground: #c7c7c7
xlogin.Login.failColor: #666666
xlogin.Login.inpColor: #121212
xlogin.Login.promptColor: #707070
xlogin.Login.greetColor: #707070
xlogin.Login.face: snap:size=8
xlogin.Login.failFace: snap:size=8
xlogin.Login.promptFace: snap:size=8
xlogin.Login.greetFace: snap:size=8
xlogin.Login.frameWidth: 0
xlogin.Login.innerFramesWidth: 0
xlogin.Login.sepWidth: 0
xlogin.Login.width: 240
xlogin.Login.height: 135
