Major Update: created v4, new configs: alacritty, polybar, i3, and more.

usr/local/bin/brightness_control

@@ -0,0 +1,30 @@
+#!/bin/sh
+
+# default
+step=+5
+
+video_card=$(ls -1 /sys/class/backlight/)
+cur_brightness=$(cat /sys/class/backlight/"$video_card"/brightness)
+max_brightness=$(cat /sys/class/backlight/"$video_card"/max_brightness)
+
+while getopts s: flag
+do
+    case "${flag}" in
+        s) step=${OPTARG};;
+        *) echo "Usage: -s <-value/+value>";;
+    esac
+
+done
+
+step=$(echo "$step" | sed 's/+//g')
+step_c=$(( (step*max_brightness)/100 ))
+# step_c=$(echo "scale=2; $step*($max_brightness/100)" | bc -l | sed 's/\..*$//')
+new_brightness=$((cur_brightness + step_c))
+
+if [ "$new_brightness" -le "0" ]; then
+    echo "0" > /sys/class/backlight/"$video_card"/brightness
+elif [ "$new_brightness" -ge "$max_brightness" ] ; then
+    echo "$max_brightness" > /sys/class/backlight/"$video_card"/brightness
+else
+    echo "$new_brightness" > /sys/class/backlight/"$video_card"/brightness
+fi