Add variables for other mod keys. Use for lock screen.

files/settings/i3.config

@@ -10,6 +10,8 @@
 # Please see https://i3wm.org/docs/userguide.html for a complete reference!
 
 set $mod Mod4
+set $alt Mod1
+set $ctrl Control
 
 # Font for window titles. Will also be used by the bar unless a different font
 # is used in the bar {} block below.
@@ -130,7 +132,7 @@ bindsym $mod+m exec thunar
 bindsym $mod+i exec firefox-flatpak
 
 # Lock
-bindsym control+mod1+l exec --no-startup-id i3lock -c 000000 -e -f && sleep 1 && xset dpms force off
+bindsym $ctrl+$alt+l exec --no-startup-id i3lock -c 000000 -e -f && sleep 1 && xset dpms force off
 
 
 ## Brightness ##