pip3 install --user --upgrade acpi-backlight
acpi-backlight-eval 1 # max brightness acpi-backlight-eval 0.5 # 50% brightness acpi-backlight-eval 1/4 # 25% brightness acpi-backlight-eval 'b + 0.1' acpi-backlight-eval 'b - 1/20' acpi-backlight-eval 'b * 1.1'