Tweak blur settings and apply it to walker

Settings by @tobi ✌️

default/hypr/looknfeel.conf

@@ -38,8 +38,11 @@ decoration {
     # https://wiki.hyprland.org/Configuring/Variables/#blur
     blur {
         enabled = true
-        size = 3
-        passes = 3
+        size = 2
+        passes = 2
+        special = true
+        brightness = 0.60
+        contrast = 0.75
     }
 }