Make background a bit less prominent

dotfiles/config/Xlib/global.Xdefaults

 !## transparency
 URxvt.inheritPixmap:        true
 !URxvt.tintColor:            red
-URxvt.shading:              25
+URxvt.shading:              20
 URxvt.depth:                32
 URxvt.fading:               30