change battery critical animation

.config/waybar/style.css

@@ -143,15 +143,13 @@ button {
 
 @keyframes blink {
   to {
-    background-color: #ffffff;
     color: #000000;
   }
 }
 
 /* Using steps() instead of linear as a timing function to limit cpu usage */
 #battery.critical:not(.charging) {
-  background-color: @red;
-  color: #ffffff;
+  color: @red;
   animation-name: blink;
   animation-duration: 0.5s;
   animation-timing-function: steps(12);