diff --git a/frontend/index.html b/frontend/index.html
index 8078a27..04a8c04 100644
--- a/frontend/index.html
+++ b/frontend/index.html
@@ -12,7 +12,7 @@
     <link rel="manifest" href="/site.webmanifest" />
     <title>Tinyauth</title>
   </head>
-  <body class="dark">
+  <body>
     <div id="root"></div>
     <script type="module" src="/src/main.tsx"></script>
   </body>
diff --git a/frontend/src/components/language/language.tsx b/frontend/src/components/language/language.tsx
index 875045c..1785ea1 100644
--- a/frontend/src/components/language/language.tsx
+++ b/frontend/src/components/language/language.tsx
@@ -18,9 +18,10 @@ export const LanguageSelector = () => {
     setLanguage(option as SupportedLanguage);
     i18n.changeLanguage(option as SupportedLanguage);
   };
+
   return (
     <Select onValueChange={handleSelect} value={language}>
-      <SelectTrigger className="absolute top-5 right-5">
+      <SelectTrigger className="bg-card">
         <SelectValue placeholder="Select language" />
       </SelectTrigger>
       <SelectContent>
diff --git a/frontend/src/components/layout/layout.tsx b/frontend/src/components/layout/layout.tsx
index 8f49e72..76cd7b6 100644
--- a/frontend/src/components/layout/layout.tsx
+++ b/frontend/src/components/layout/layout.tsx
@@ -3,6 +3,7 @@ import { LanguageSelector } from "../language/language";
 import { Outlet } from "react-router";
 import { useCallback, useEffect, useState } from "react";
 import { DomainWarning } from "../domain-warning/domain-warning";
+import { ThemeSwitch } from "../theme-switch/theme-switch";
 
 const BaseLayout = ({ children }: { children: React.ReactNode }) => {
   const { backgroundImage, title } = useAppContext();
@@ -20,7 +21,10 @@ const BaseLayout = ({ children }: { children: React.ReactNode }) => {
         backgroundPosition: "center",
       }}
     >
-      <LanguageSelector />
+      <div className="absolute top-5 right-5 flex flex-row gap-2">
+        <ThemeSwitch />
+        <LanguageSelector />
+      </div>
       {children}
     </div>
   );
diff --git a/frontend/src/components/providers/theme-provider.tsx b/frontend/src/components/providers/theme-provider.tsx
new file mode 100644
index 0000000..4a338ea
--- /dev/null
+++ b/frontend/src/components/providers/theme-provider.tsx
@@ -0,0 +1,53 @@
+import React from "react";
+import { createContext, useEffect, useState } from "react";
+
+interface ThemeSchema {
+  darkMode: boolean;
+  setDarkMode: (darkMode: boolean) => void;
+}
+
+const ThemeContext = createContext<ThemeSchema | null>(null);
+
+export const ThemeProvider = ({ children }: { children: React.ReactNode }) => {
+  const [darkMode, setDarkMode] = useState<boolean>(false);
+
+  useEffect(() => {
+    const storedTheme = localStorage.getItem("tinyauth-theme");
+    if (storedTheme) {
+      setDarkMode(storedTheme === "dark");
+      return;
+    }
+    const prefersDark = window.matchMedia(
+      "(prefers-color-scheme: dark)",
+    ).matches;
+    setDarkMode(prefersDark);
+  }, []);
+
+  useEffect(() => {
+    const rootElement = document.documentElement;
+    rootElement.classList.remove("dark", "light");
+    rootElement.classList.add(darkMode ? "dark" : "light");
+  }, [darkMode]);
+
+  const values = {
+    darkMode,
+    setDarkMode: (darkMode: boolean) => {
+      localStorage.setItem("tinyauth-theme", darkMode ? "dark" : "light");
+      setDarkMode(darkMode);
+    },
+  };
+
+  return (
+    <ThemeContext.Provider value={values}>{children}</ThemeContext.Provider>
+  );
+};
+
+export const useTheme = () => {
+  const context = React.useContext(ThemeContext);
+
+  if (!context) {
+    throw new Error("useTheme must be used within a ThemeProvider");
+  }
+
+  return context;
+};
diff --git a/frontend/src/components/theme-switch/theme-switch.tsx b/frontend/src/components/theme-switch/theme-switch.tsx
new file mode 100644
index 0000000..9fea737
--- /dev/null
+++ b/frontend/src/components/theme-switch/theme-switch.tsx
@@ -0,0 +1,23 @@
+import { MoonIcon, SunIcon } from "lucide-react";
+import { useTheme } from "../providers/theme-provider";
+import { Button } from "../ui/button";
+
+export const ThemeSwitch = () => {
+  const { darkMode, setDarkMode } = useTheme();
+
+  const toggleTheme = () => {
+    setDarkMode(!darkMode);
+  };
+
+  return (
+    <Button
+      className="bg-card hover:bg-card/90 text-card-foreground"
+      aria-label={`Switch to ${darkMode ? "light" : "dark"} mode`}
+      onClick={() => {
+        toggleTheme();
+      }}
+    >
+      {darkMode ? <SunIcon /> : <MoonIcon />}
+    </Button>
+  );
+};
diff --git a/frontend/src/components/ui/button.tsx b/frontend/src/components/ui/button.tsx
index 4badcc1..0ee404c 100644
--- a/frontend/src/components/ui/button.tsx
+++ b/frontend/src/components/ui/button.tsx
@@ -6,7 +6,7 @@ import { cn } from "@/lib/utils";
 import { Loader2 } from "lucide-react";
 
 const buttonVariants = cva(
-  "inline-flex items-center justify-center gap-2 whitespace-nowrap rounded-md text-sm font-medium transition-all disabled:pointer-events-none disabled:opacity-50 [&_svg]:pointer-events-none [&_svg:not([class*='size-'])]:size-4 shrink-0 [&_svg]:shrink-0 outline-none focus-visible:border-ring focus-visible:ring-ring/50 focus-visible:ring-[3px] aria-invalid:ring-destructive/20 dark:aria-invalid:ring-destructive/40 aria-invalid:border-destructive",
+  "inline-flex items-center justify-center gap-2 whitespace-nowrap rounded-md text-sm font-medium transition-all disabled:pointer-events-none disabled:opacity-50 [&_svg]:pointer-events-none [&_svg:not([class*='size-'])]:size-4 shrink-0 [&_svg]:shrink-0 outline-none focus-visible:border-ring focus-visible:ring-ring/50 focus-visible:ring-[3px] aria-invalid:ring-destructive/20 dark:aria-invalid:ring-destructive/40 aria-invalid:border-destructive hover:cursor-pointer",
   {
     variants: {
       variant: {
diff --git a/frontend/src/components/ui/select.tsx b/frontend/src/components/ui/select.tsx
index c0b69e8..541d317 100644
--- a/frontend/src/components/ui/select.tsx
+++ b/frontend/src/components/ui/select.tsx
@@ -35,7 +35,7 @@ function SelectTrigger({
       data-slot="select-trigger"
       data-size={size}
       className={cn(
-        "border-input data-[placeholder]:text-muted-foreground [&_svg:not([class*='text-'])]:text-muted-foreground focus-visible:border-ring focus-visible:ring-ring/50 aria-invalid:ring-destructive/20 dark:aria-invalid:ring-destructive/40 aria-invalid:border-destructive dark:bg-card dark:hover:bg-card/90 flex w-fit items-center justify-between gap-2 rounded-md border bg-card hover:bg-card/90 px-3 py-2 text-sm whitespace-nowrap shadow-xs transition-[color,box-shadow] outline-none focus-visible:ring-[3px] disabled:cursor-not-allowed disabled:opacity-50 data-[size=default]:h-9 data-[size=sm]:h-8 *:data-[slot=select-value]:line-clamp-1 *:data-[slot=select-value]:flex *:data-[slot=select-value]:items-center *:data-[slot=select-value]:gap-2 [&_svg]:pointer-events-none [&_svg]:shrink-0 [&_svg:not([class*='size-'])]:size-4",
+        "hover:cursor-pointer border-input data-[placeholder]:text-card-foreground [&_svg:not([class*='text-'])]:text-card-foreground focus-visible:border-ring focus-visible:ring-ring/50 aria-invalid:ring-destructive/20 dark:aria-invalid:ring-destructive/40 aria-invalid:border-destructive dark:bg-card dark:hover:bg-card/90 flex w-fit items-center justify-between gap-2 rounded-md border bg-card hover:bg-card/90 px-3 py-2 text-sm whitespace-nowrap shadow-xs transition-[color,box-shadow] outline-none focus-visible:ring-[3px] disabled:cursor-not-allowed disabled:opacity-50 data-[size=default]:h-9 data-[size=sm]:h-8 *:data-[slot=select-value]:line-clamp-1 *:data-[slot=select-value]:flex *:data-[slot=select-value]:items-center *:data-[slot=select-value]:gap-2 [&_svg]:pointer-events-none [&_svg]:shrink-0 [&_svg:not([class*='size-'])]:size-4",
         className,
       )}
       {...props}
diff --git a/frontend/src/components/ui/sonner.tsx b/frontend/src/components/ui/sonner.tsx
index 59f9447..7284cbf 100644
--- a/frontend/src/components/ui/sonner.tsx
+++ b/frontend/src/components/ui/sonner.tsx
@@ -1,8 +1,9 @@
-import { useTheme } from "next-themes";
+import { useTheme } from "../providers/theme-provider";
 import { Toaster as Sonner, ToasterProps } from "sonner";
 
 const Toaster = ({ ...props }: ToasterProps) => {
-  const { theme = "system" } = useTheme();
+  const { darkMode } = useTheme();
+  const theme = darkMode ? "dark" : "light";
 
   return (
     <Sonner
diff --git a/frontend/src/main.tsx b/frontend/src/main.tsx
index b79bbdb..f8296c8 100644
--- a/frontend/src/main.tsx
+++ b/frontend/src/main.tsx
@@ -16,6 +16,7 @@ import { QueryClient, QueryClientProvider } from "@tanstack/react-query";
 import { AppContextProvider } from "./context/app-context.tsx";
 import { UserContextProvider } from "./context/user-context.tsx";
 import { Toaster } from "@/components/ui/sonner";
+import { ThemeProvider } from "./components/providers/theme-provider.tsx";
 
 const queryClient = new QueryClient();
 
@@ -24,25 +25,27 @@ createRoot(document.getElementById("root")!).render(
     <QueryClientProvider client={queryClient}>
       <AppContextProvider>
         <UserContextProvider>
-          <BrowserRouter>
-            <Routes>
-              <Route element={<Layout />} errorElement={<ErrorPage />}>
-                <Route path="/" element={<App />} />
-                <Route path="/login" element={<LoginPage />} />
-                <Route path="/logout" element={<LogoutPage />} />
-                <Route path="/continue" element={<ContinuePage />} />
-                <Route path="/totp" element={<TotpPage />} />
-                <Route
-                  path="/forgot-password"
-                  element={<ForgotPasswordPage />}
-                />
-                <Route path="/unauthorized" element={<UnauthorizedPage />} />
-                <Route path="/error" element={<ErrorPage />} />
-                <Route path="*" element={<NotFoundPage />} />
-              </Route>
-            </Routes>
-          </BrowserRouter>
-          <Toaster />
+          <ThemeProvider>
+            <BrowserRouter>
+              <Routes>
+                <Route element={<Layout />} errorElement={<ErrorPage />}>
+                  <Route path="/" element={<App />} />
+                  <Route path="/login" element={<LoginPage />} />
+                  <Route path="/logout" element={<LogoutPage />} />
+                  <Route path="/continue" element={<ContinuePage />} />
+                  <Route path="/totp" element={<TotpPage />} />
+                  <Route
+                    path="/forgot-password"
+                    element={<ForgotPasswordPage />}
+                  />
+                  <Route path="/unauthorized" element={<UnauthorizedPage />} />
+                  <Route path="/error" element={<ErrorPage />} />
+                  <Route path="*" element={<NotFoundPage />} />
+                </Route>
+              </Routes>
+            </BrowserRouter>
+            <Toaster />
+          </ThemeProvider>
         </UserContextProvider>
       </AppContextProvider>
     </QueryClientProvider>
