feat: added night light as a dconf option

configurations/home-manager/eve/gnomeconf.nix

@@ -8,6 +8,14 @@
       {
         colorScheme = "prefer-dark";
         accentColor = "slate";
+        clockFormat = "24h";
+        nightLight = {
+          enable = true;
+          automatic = false;
+          fromTime = 12.0;
+          toTime = 11.999999999999;
+          temperature = 2700;
+        };
         extraWindowControls = true;
         extensions = {
           dash-to-panel = {

configurations/home-manager/leyla/dconf.nix

@@ -4,6 +4,13 @@
       extraWindowControls = true;
       colorScheme = "prefer-dark";
       clockFormat = "24h";
+      nightLight = {
+        enable = true;
+        automatic = false;
+        fromTime = 12.0;
+        toTime = 11.999999999999;
+        temperature = 2700;
+      };
       extensions = {
         dash-to-dock = {
           enable = true;

modules/home-manager-modules/gnome.nix

@@ -81,6 +81,36 @@ in {
       description = "GNOME experimental features to enable";
     };
 
+    nightLight = lib.mkOption {
+      type = lib.types.submodule {
+        options = {
+          enable = lib.mkEnableOption "night light (blue light filter)";
+          automatic = lib.mkOption {
+            type = lib.types.bool;
+            default = true;
+            description = "Whether to automatically schedule night light based on sunset/sunrise";
+          };
+          fromTime = lib.mkOption {
+            type = lib.types.float;
+            default = 20.0;
+            description = "Start time for night light in 24-hour format (e.g., 20.0 for 8:00 PM)";
+          };
+          toTime = lib.mkOption {
+            type = lib.types.float;
+            default = 6.0;
+            description = "End time for night light in 24-hour format (e.g., 6.0 for 6:00 AM)";
+          };
+          temperature = lib.mkOption {
+            type = lib.types.int;
+            default = 4000;
+            description = "Color temperature for night light (1000-10000K, lower is warmer)";
+          };
+        };
+      };
+      default = {};
+      description = "Night light configuration";
+    };
+
     extensions = {
       dash-to-dock = {
         enable = lib.mkEnableOption "Dash to Dock extension";
@@ -123,6 +153,17 @@ in {
             lib.optional config.gnome.experimentalFeatures.scaleMonitorFramebuffer "scale-monitor-framebuffer"
           );
         }
+
+        # Night light configuration
+        (lib.mkIf config.gnome.nightLight.enable {
+          "org/gnome/settings-daemon/plugins/color" = {
+            night-light-enabled = true;
+            night-light-schedule-automatic = config.gnome.nightLight.automatic;
+            night-light-schedule-from = lib.mkIf (!config.gnome.nightLight.automatic) config.gnome.nightLight.fromTime;
+            night-light-schedule-to = lib.mkIf (!config.gnome.nightLight.automatic) config.gnome.nightLight.toTime;
+            night-light-temperature = config.gnome.nightLight.temperature;
+          };
+        })
         (
           lib.mkMerge (
             builtins.map (value: let