diff --git a/flake.lock b/flake.lock
index 9bd5e7c..02d91fb 100644
--- a/flake.lock
+++ b/flake.lock
@@ -74,11 +74,11 @@
         ]
       },
       "locked": {
-        "lastModified": 1748659443,
-        "narHash": "sha256-dav2hzyCmXZ3n6lEZrfZBG51+g6PUhkzRl3d6Ypd9x0=",
+        "lastModified": 1751622568,
+        "narHash": "sha256-EE3NBsej517VRa1x+ylAghrvngftxf1KgfHlE9OYyXE=",
         "owner": "nix-community",
         "repo": "nixos-apple-silicon",
-        "rev": "3ddc251d2acce5019b0fa770e224d068610a34e4",
+        "rev": "eba4b40c816e5aff8951ae231ac237e8aab8ec1d",
         "type": "github"
       },
       "original": {
@@ -326,11 +326,11 @@
         ]
       },
       "locked": {
-        "lastModified": 1749398372,
-        "narHash": "sha256-tYBdgS56eXYaWVW3fsnPQ/nFlgWi/Z2Ymhyu21zVM98=",
+        "lastModified": 1751413152,
+        "narHash": "sha256-Tyw1RjYEsp5scoigs1384gIg6e0GoBVjms4aXFfRssQ=",
         "owner": "hercules-ci",
         "repo": "flake-parts",
-        "rev": "9305fe4e5c2a6fcf5ba6a3ff155720fbe4076569",
+        "rev": "77826244401ea9de6e3bac47c2db46005e1f30b5",
         "type": "github"
       },
       "original": {
@@ -446,16 +446,16 @@
     "gnome-shell": {
       "flake": false,
       "locked": {
-        "lastModified": 1744584021,
-        "narHash": "sha256-0RJ4mJzf+klKF4Fuoc8VN8dpQQtZnKksFmR2jhWE1Ew=",
+        "lastModified": 1748186689,
+        "narHash": "sha256-UaD7Y9f8iuLBMGHXeJlRu6U1Ggw5B9JnkFs3enZlap0=",
         "owner": "GNOME",
         "repo": "gnome-shell",
-        "rev": "52c517c8f6c199a1d6f5118fae500ef69ea845ae",
+        "rev": "8c88f917db0f1f0d80fa55206c863d3746fa18d0",
         "type": "github"
       },
       "original": {
         "owner": "GNOME",
-        "ref": "48.1",
+        "ref": "48.2",
         "repo": "gnome-shell",
         "type": "github"
       }
@@ -489,11 +489,11 @@
         ]
       },
       "locked": {
-        "lastModified": 1751146119,
-        "narHash": "sha256-gvjG95TCnUVJkvQvLMlnC4NqiqFyBdJk3o8/RwuHeaU=",
+        "lastModified": 1751760902,
+        "narHash": "sha256-qBGNn7T/zOgUDQTo/RM/D2oxMkB2x36j3ajvpVanEVs=",
         "owner": "nix-community",
         "repo": "home-manager",
-        "rev": "76d0c31fce2aa0c71409de953e2f9113acd5b656",
+        "rev": "8b0180dde1d6f4cf632e046309e8f963924dfbd0",
         "type": "github"
       },
       "original": {
@@ -510,11 +510,11 @@
         ]
       },
       "locked": {
-        "lastModified": 1748737919,
-        "narHash": "sha256-5kvBbLYdp+n7Ftanjcs6Nv+UO6sBhelp6MIGJ9nWmjQ=",
+        "lastModified": 1751146119,
+        "narHash": "sha256-gvjG95TCnUVJkvQvLMlnC4NqiqFyBdJk3o8/RwuHeaU=",
         "owner": "nix-community",
         "repo": "home-manager",
-        "rev": "5675a9686851d9626560052a032c4e14e533c1fa",
+        "rev": "76d0c31fce2aa0c71409de953e2f9113acd5b656",
         "type": "github"
       },
       "original": {
@@ -526,11 +526,11 @@
     "homebrew-cask": {
       "flake": false,
       "locked": {
-        "lastModified": 1751137566,
-        "narHash": "sha256-gs7kNlWUBZALAe4nUzfBLtzYrTqc+RnmqvpMlkff6+E=",
+        "lastModified": 1751761814,
+        "narHash": "sha256-fFsGoD37BEJ+xEwJV8ixGqJbDF2XWlNHWN7D4NkIuIc=",
         "owner": "homebrew",
         "repo": "homebrew-cask",
-        "rev": "8dea2358bca3dc55c8b562b69765b25189cce353",
+        "rev": "5dca1c162b0bd3fc91c9035d41be00df629a14ca",
         "type": "github"
       },
       "original": {
@@ -542,11 +542,11 @@
     "homebrew-core": {
       "flake": false,
       "locked": {
-        "lastModified": 1751148439,
-        "narHash": "sha256-7E/PggJcX4ezFeufDeXhiMVgWy+akCX6yszDbDoi8ss=",
+        "lastModified": 1751761822,
+        "narHash": "sha256-jvC8mqTESUbuveVCECi/OTPZA/qxoApL3b6TY1Ecz+4=",
         "owner": "homebrew",
         "repo": "homebrew-core",
-        "rev": "c7fac280ef6b96c8df34be6a530a2506fed5e6d2",
+        "rev": "5ebe6deb98aff153df53aec524710756c41e1102",
         "type": "github"
       },
       "original": {
@@ -634,11 +634,11 @@
         ]
       },
       "locked": {
-        "lastModified": 1750618568,
-        "narHash": "sha256-w9EG5FOXrjXGfbqCcQg9x1lMnTwzNDW5BMXp8ddy15E=",
+        "lastModified": 1751313918,
+        "narHash": "sha256-HsJM3XLa43WpG+665aGEh8iS8AfEwOIQWk3Mke3e7nk=",
         "owner": "LnL7",
         "repo": "nix-darwin",
-        "rev": "1dd19f19e4b53a1fd2e8e738a08dd5fe635ec7e5",
+        "rev": "e04a388232d9a6ba56967ce5b53a8a6f713cdfcf",
         "type": "github"
       },
       "original": {
@@ -649,11 +649,11 @@
     },
     "nix-flatpak": {
       "locked": {
-        "lastModified": 1749394952,
-        "narHash": "sha256-WbWkzIvB0gqAdBLghdmUpGveY7MlAS2iMj3VEJnJ9yE=",
+        "lastModified": 1751276396,
+        "narHash": "sha256-oOYrnKStMsOXST+wKnzuSZ49h8Dr1Q3mIn2f5Kb5GAw=",
         "owner": "gmodena",
         "repo": "nix-flatpak",
-        "rev": "64c6e53a3999957c19ab95cda78bde466d8374cc",
+        "rev": "59adb9ad1cbd915494fc35cd0e0a9d582ca9de74",
         "type": "github"
       },
       "original": {
@@ -687,11 +687,11 @@
         ]
       },
       "locked": {
-        "lastModified": 1750565152,
-        "narHash": "sha256-A6ZIoIgaPPkzIVxKuaxwEJicPOeTwC/MD9iuC3FVhDM=",
+        "lastModified": 1751170039,
+        "narHash": "sha256-3EKpUmyGmHYA/RuhZjINTZPU+OFWko0eDwazUOW64nw=",
         "owner": "nix-community",
         "repo": "nix-index-database",
-        "rev": "78cd697acc2e492b4e92822a4913ffad279c20e6",
+        "rev": "9c932ae632d6b5150515e5749b198c175d8565db",
         "type": "github"
       },
       "original": {
@@ -770,11 +770,11 @@
     },
     "nixpkgs_2": {
       "locked": {
-        "lastModified": 1751011381,
-        "narHash": "sha256-krGXKxvkBhnrSC/kGBmg5MyupUUT5R6IBCLEzx9jhMM=",
+        "lastModified": 1751637120,
+        "narHash": "sha256-xVNy/XopSfIG9c46nRmPaKfH1Gn/56vQ8++xWA8itO4=",
         "owner": "nixos",
         "repo": "nixpkgs",
-        "rev": "30e2e2857ba47844aa71991daa6ed1fc678bcbb7",
+        "rev": "5c724ed1388e53cc231ed98330a60eb2f7be4be3",
         "type": "github"
       },
       "original": {
@@ -807,15 +807,14 @@
         ],
         "nixpkgs": [
           "nixpkgs"
-        ],
-        "treefmt-nix": "treefmt-nix"
+        ]
       },
       "locked": {
-        "lastModified": 1751150016,
-        "narHash": "sha256-aaNJgaEXYMsdmLG38YyCO0eZdTf49Cj0TZsW4gpn9jg=",
+        "lastModified": 1751754818,
+        "narHash": "sha256-gARxzPFRzgIV8IURddZP65AAPMuiXU3DqResBrunvz8=",
         "owner": "nix-community",
         "repo": "NUR",
-        "rev": "c3c9ee3b26349abe162df39499ec587f453ce089",
+        "rev": "feddc752c19779132fa6b904b2cb261e0e29e77a",
         "type": "github"
       },
       "original": {
@@ -834,7 +833,7 @@
           "stylix",
           "nixpkgs"
         ],
-        "treefmt-nix": "treefmt-nix_2"
+        "treefmt-nix": "treefmt-nix"
       },
       "locked": {
         "lastModified": 1748730660,
@@ -976,11 +975,11 @@
         "systems": "systems_3"
       },
       "locked": {
-        "lastModified": 1750567035,
-        "narHash": "sha256-GVNXxMZynKZt+83QQQEVXscqtkJbScvaBrwianovUW4=",
+        "lastModified": 1751171964,
+        "narHash": "sha256-SeVvQm9ex+6BhDPIsRt9E1kSmMblQ6gTi53baphnX08=",
         "owner": "Gerg-L",
         "repo": "spicetify-nix",
-        "rev": "e32285f5d1dfc184b039a813644e226c3914e7d7",
+        "rev": "16adc163d966fc2bb5da47580df4602ae2c7a310",
         "type": "github"
       },
       "original": {
@@ -1015,11 +1014,11 @@
         "tinted-zed": "tinted-zed"
       },
       "locked": {
-        "lastModified": 1751145558,
-        "narHash": "sha256-OPlbpH64jzIspYqvJB96tnN9V9HBlAxROS5ijQwtN70=",
+        "lastModified": 1751656637,
+        "narHash": "sha256-x1uJ6wQ7C+N/Zx9liQzjyVOEwGf5tcKogSoGgxASZOg=",
         "owner": "danth",
         "repo": "stylix",
-        "rev": "3a09d3f5cb940fa4142a2f3415b508a8be92b721",
+        "rev": "606944b16862d43934fec3311f9cb9f478b7f99b",
         "type": "github"
       },
       "original": {
@@ -1193,27 +1192,6 @@
       }
     },
     "treefmt-nix": {
-      "inputs": {
-        "nixpkgs": [
-          "nur",
-          "nixpkgs"
-        ]
-      },
-      "locked": {
-        "lastModified": 1733222881,
-        "narHash": "sha256-JIPcz1PrpXUCbaccEnrcUS8jjEb/1vJbZz5KkobyFdM=",
-        "owner": "numtide",
-        "repo": "treefmt-nix",
-        "rev": "49717b5af6f80172275d47a418c9719a31a78b53",
-        "type": "github"
-      },
-      "original": {
-        "owner": "numtide",
-        "repo": "treefmt-nix",
-        "type": "github"
-      }
-    },
-    "treefmt-nix_2": {
       "inputs": {
         "nixpkgs": [
           "stylix",
@@ -1315,11 +1293,11 @@
         ]
       },
       "locked": {
-        "lastModified": 1750219862,
-        "narHash": "sha256-wce+erYDBm6wpLJm6IJh85KYqy/NtdKp6DZQCn4YP1Q=",
+        "lastModified": 1751688498,
+        "narHash": "sha256-6kYe6ozYDvsHAxV1zbSxg0oRWF4TzTfOUUJsR6MJlYY=",
         "owner": "youwen5",
         "repo": "zen-browser-flake",
-        "rev": "18d6cd2f5a9cd1527d478d4f716e9b9ee6fb6cbb",
+        "rev": "b5d422dc2b28eb77a21fbdf60aca9a6e63d5a1ab",
         "type": "github"
       },
       "original": {
diff --git a/modules/linux/core/default.nix b/modules/linux/core/default.nix
index 768fb63..29e7345 100644
--- a/modules/linux/core/default.nix
+++ b/modules/linux/core/default.nix
@@ -107,6 +107,8 @@ in
 
     services.gnome.gnome-keyring.enable = true;
 
+    services.resolved.enable = true;
+
     nix = lib.mkIf cfg.nixSaneDefaults {
       gc = lib.mkIf (!cfg.useNh) {
         automatic = true;
diff --git a/reference/hosts/callisto/configuration.nix b/reference/hosts/callisto/configuration.nix
index bbf20d0..aa10863 100755
--- a/reference/hosts/callisto/configuration.nix
+++ b/reference/hosts/callisto/configuration.nix
@@ -11,7 +11,8 @@
   imports = [ ./hardware-configuration.nix ];
 
   networking.hostName = "callisto";
-  time.timeZone = "America/Los_Angeles";
+  # time.timeZone = "America/Los_Angeles";
+  time.timeZone = "Asia/Shanghai";
 
   liminalOS = {
     flakeLocation = "/home/youwen/.config/liminalOS";
@@ -27,6 +28,11 @@
     };
   };
 
+  services.mullvad-vpn = {
+    enable = true;
+    package = pkgs.mullvad-vpn;
+  };
+
   boot = {
     loader.systemd-boot.enable = true;
     loader.efi.canTouchEfiVariables = false;