diff --git a/package/contents/ui/lib/helper.js b/package/contents/ui/lib/helper.js
index 4984a62..32b19d3 100644
--- a/package/contents/ui/lib/helper.js
+++ b/package/contents/ui/lib/helper.js
@@ -3,23 +3,17 @@ const colors = [
   '#718d00', '#6fa100', '#5c8000', '#498000', '#080'
 ];
 
-function batteryColor(batteryPercent) {
-  return colors[({
-    "-2": 9,
-    "-1": 0
-  })[batteryPercent] ?? ~~(batteryPercent / 10 + 0.5) - 1];
-}
+const batteryColor = batteryPercent => colors[({
+  "-2": 9,
+  "-1": 0
+})[batteryPercent] ?? ~~(batteryPercent / 10 + 0.5) - 1];
 
-function batteryLevel(batteryPercent) {
-  return ({
-    "-2": "not connected",
-    "-1": "charging"
-  })[batteryPercent] ?? batteryPercent + "%";
-}
+const batteryLevel = batteryPercent => ({
+  "-2": "not connected",
+  "-1": "charging"
+})[batteryPercent] ?? batteryPercent + "%";
 
-function batteryIcon(batteryPercent) {
-  return ({
-    "-2": "action-unavailable",
-    "-1": "battery-ac-adapter"
-  })[batteryPercent] ?? "audio-headphones-symbolic";
-}
+const batteryIcon = batteryPercent => ({
+  "-2": "action-unavailable",
+  "-1": "battery-ac-adapter"
+})[batteryPercent] ?? "audio-headphones-symbolic";