diff --git a/app/globals.css b/app/globals.css
index 3fca1ca..0bc92ed 100644
--- a/app/globals.css
+++ b/app/globals.css
@@ -78,49 +78,7 @@
   --radius-4xl: calc(var(--radius) * 2.6);
 }
 
-:root {
-  color-scheme: light;
-  --background: oklch(0.985 0.004 88);
-  --foreground: oklch(0.22 0.018 275);
-  --card: oklch(1 0 0);
-  --card-foreground: var(--foreground);
-  --popover: oklch(1 0 0);
-  --popover-foreground: var(--foreground);
-  --primary: oklch(0.51 0.105 78);
-  --primary-foreground: oklch(0.99 0.005 88);
-  --secondary: oklch(0.94 0.01 274);
-  --secondary-foreground: var(--foreground);
-  --muted: oklch(0.955 0.008 274);
-  --muted-foreground: oklch(0.48 0.02 274);
-  --accent: oklch(0.93 0.015 275);
-  --accent-foreground: var(--foreground);
-  --destructive: oklch(0.54 0.2 25);
-  --success: oklch(0.46 0.12 155);
-  --warning: oklch(0.51 0.105 78);
-  --info: oklch(0.47 0.11 235);
-  --tier-gold: oklch(0.51 0.105 78);
-  --tier-silver: oklch(0.48 0.02 260);
-  --tier-copper: oklch(0.49 0.1 55);
-  --border: oklch(0.22 0.018 275 / 15%);
-  --input: oklch(0.22 0.018 275 / 22%);
-  --ring: var(--primary);
-  --chart-1: oklch(0.51 0.105 78);
-  --chart-2: oklch(0.5 0.15 255);
-  --chart-3: oklch(0.46 0.12 155);
-  --chart-4: oklch(0.5 0.16 325);
-  --chart-5: oklch(0.47 0.1 210);
-  --chart-6: oklch(0.54 0.17 25);
-  --radius: 0.625rem;
-  --sidebar: oklch(0.965 0.008 274);
-  --sidebar-foreground: var(--foreground);
-  --sidebar-primary: var(--primary);
-  --sidebar-primary-foreground: var(--primary-foreground);
-  --sidebar-accent: var(--accent);
-  --sidebar-accent-foreground: var(--foreground);
-  --sidebar-border: var(--border);
-  --sidebar-ring: var(--ring);
-}
-
+:root,
 .dark {
   color-scheme: dark;
   --background: oklch(0.13 0.012 275);
diff --git a/app/layout.tsx b/app/layout.tsx
index 4fc51b7..fce3b1a 100644
--- a/app/layout.tsx
+++ b/app/layout.tsx
@@ -3,7 +3,6 @@ import { Anuphan, Geist_Mono } from "next/font/google";
 
 import { DeploymentUpdateNotifier } from "@/components/deployment-update-notifier";
 import { PageProgress } from "@/components/page-progress";
-import { ThemeProvider } from "@/components/theme-provider";
 import { Toaster } from "@/components/ui/sonner";
 import { NotificationProvider } from "@/components/notifications/notification-bell";
 import { SitePushPrompt } from "@/components/notifications/site-push-prompt";
@@ -45,24 +44,21 @@ export default function RootLayout({ children }: LayoutProps<"/">) {
   return (
     <html
       lang="th"
-      className={`${anuphan.variable} ${geistMono.variable} h-full antialiased`}
-      suppressHydrationWarning
+      className={`dark ${anuphan.variable} ${geistMono.variable} h-full antialiased`}
     >
       <body className="flex min-h-full flex-col">
-        <ThemeProvider>
-          <PageProgress />
-          <NotificationProvider>
-            {children}
-            <SitePushPrompt configured={Boolean(process.env.WEB_PUSH_PUBLIC_KEY && process.env.WEB_PUSH_PRIVATE_KEY && process.env.WEB_PUSH_SUBJECT)} />
-          </NotificationProvider>
-          <DeploymentUpdateNotifier deploymentId={deploymentId} />
-          <Toaster
-            richColors
-            closeButton
-            position="bottom-right"
-            toastOptions={{ className: anuphan.className }}
-          />
-        </ThemeProvider>
+        <PageProgress />
+        <NotificationProvider>
+          {children}
+          <SitePushPrompt configured={Boolean(process.env.WEB_PUSH_PUBLIC_KEY && process.env.WEB_PUSH_PRIVATE_KEY && process.env.WEB_PUSH_SUBJECT)} />
+        </NotificationProvider>
+        <DeploymentUpdateNotifier deploymentId={deploymentId} />
+        <Toaster
+          richColors
+          closeButton
+          position="bottom-right"
+          toastOptions={{ className: anuphan.className }}
+        />
       </body>
     </html>
   );
diff --git a/bun.lock b/bun.lock
index aa2a0d6..789fa19 100644
--- a/bun.lock
+++ b/bun.lock
@@ -36,7 +36,6 @@
         "lucide-react": "^1.35.0",
         "modern-screenshot": "^4.7.0",
         "next": "^16.4.0",
-        "next-themes": "^0.4.6",
         "postgres": "^3.4.9",
         "qrcode": "^1.5.4",
         "radix-ui": "^1.6.7",
@@ -1544,8 +1543,6 @@
 
     "next": ["next@16.4.0", "", { "dependencies": { "@next/env": "16.4.0", "@swc/helpers": "0.5.23", "baseline-browser-mapping": "^2.9.19", "caniuse-lite": "^1.0.30001579", "postcss": "8.5.23", "styled-jsx": "5.1.6" }, "optionalDependencies": { "@next/swc-darwin-arm64": "16.4.0", "@next/swc-darwin-x64": "16.4.0", "@next/swc-linux-arm64-gnu": "16.4.0", "@next/swc-linux-arm64-musl": "16.4.0", "@next/swc-linux-x64-gnu": "16.4.0", "@next/swc-linux-x64-musl": "16.4.0", "@next/swc-win32-arm64-msvc": "16.4.0", "@next/swc-win32-x64-msvc": "16.4.0", "sharp": "^0.35.4" }, "peerDependencies": { "@opentelemetry/api": "^1.1.0", "@playwright/test": "^1.51.1", "babel-plugin-react-compiler": "*", "react": "^18.2.0 || 19.0.0-rc-de68d2f4-20241204 || ^19.0.0", "react-dom": "^18.2.0 || 19.0.0-rc-de68d2f4-20241204 || ^19.0.0", "sass": "^1.3.0" }, "optionalPeers": ["@opentelemetry/api", "@playwright/test", "babel-plugin-react-compiler", "sass"], "bin": { "next": "dist/bin/next" } }, "sha512-N2C+9q89Z/oLrsepSRS4jRMtwmUZAoZuAHU0e9T6+sAB5DdhADmrnOW+zjYijlrYFmVfmQhGVGy9eMFoB7UgKg=="],
 
-    "next-themes": ["next-themes@0.4.6", "", { "peerDependencies": { "react": "^16.8 || ^17 || ^18 || ^19 || ^19.0.0-rc", "react-dom": "^16.8 || ^17 || ^18 || ^19 || ^19.0.0-rc" } }, "sha512-pZvgD5L0IEvX5/9GWyHMf3m8BKiVQwsCMHfoFosXtXBMnaS0ZnIJ9ST4b4NqLVKDEm8QBxoNNGNaBv2JNF6XNA=="],
-
     "node-exports-info": ["node-exports-info@1.6.2", "", { "dependencies": { "array.prototype.flatmap": "^1.3.3", "es-errors": "^1.3.0", "object.entries": "^1.1.9", "semver": "^6.3.1" } }, "sha512-kXs9Go0cah0qHVV2v389IXQLdLCeE1xfFtjOAF+iobu0OIoG1pje8At2vMHyaPMiPMnG/LWP50twML21eMcAag=="],
 
     "node-releases": ["node-releases@2.0.54", "", {}, "sha512-YHs7BmmcsdAI5Ozuf8JZo6PT0mv2GIWC9vMfvUC3dp65M8hn7Ux8CPL+2oBI7juNuj9d0ndhTcznq2ODBps9cQ=="],
diff --git a/components/admin/overview-image-generator.tsx b/components/admin/overview-image-generator.tsx
index 3401266..bf41fa8 100644
--- a/components/admin/overview-image-generator.tsx
+++ b/components/admin/overview-image-generator.tsx
@@ -279,7 +279,7 @@ function OverviewPoster({
     <DndContext sensors={posterSensors} onDragEnd={handlePosterDragEnd}>
       <div
         ref={posterRef}
-        className="dark relative isolate aspect-square size-full overflow-hidden bg-black text-white @container"
+        className="relative isolate aspect-square size-full overflow-hidden bg-black text-white @container"
         style={{ fontFamily: '"Genshin Overview", sans-serif' }}
       >
       {composition.backgroundUrl ? (
diff --git a/components/header-shell.tsx b/components/header-shell.tsx
index 302317e..73d35ec 100644
--- a/components/header-shell.tsx
+++ b/components/header-shell.tsx
@@ -4,7 +4,6 @@ import Link from "next/link";
 import Image from "@/components/ui/resilient-image";
 import { PublicAccountMenu } from "@/components/public/public-account-menu";
 import { NotificationBell } from "@/components/notifications/notification-bell";
-import { ThemeSwitcher } from "@/components/theme-switcher";
 
 export function HeaderShell({ homeHref, homeLabel, children }: {
   homeHref: string;
@@ -23,7 +22,6 @@ export function HeaderShell({ homeHref, homeLabel, children }: {
           <span className="hidden lg:inline">ไกด์เกนชินไม่ใช่เกมมือถือ</span>
         </Link>
         {children}
-        <ThemeSwitcher />
         <NotificationBell />
         <PublicAccountMenu />
       </div>
diff --git a/components/public/constellation-image.tsx b/components/public/constellation-image.tsx
index 01d1d84..10119d8 100644
--- a/components/public/constellation-image.tsx
+++ b/components/public/constellation-image.tsx
@@ -35,7 +35,7 @@ export function ConstellationImage({
   const footer = group.note;
 
   return (
-    <div className="dark relative isolate size-375 overflow-hidden bg-[#070b20] font-heading text-white">
+    <div className="relative isolate size-375 overflow-hidden bg-[#070b20] font-heading text-white">
       <GuideExportBranding backgroundUrl={background} variant="constellation" />
 
       <div className="absolute inset-x-20 top-7 z-10 flex items-start justify-center gap-5">
diff --git a/components/public/guide-image-export.tsx b/components/public/guide-image-export.tsx
index 122a45c..632d50b 100644
--- a/components/public/guide-image-export.tsx
+++ b/components/public/guide-image-export.tsx
@@ -496,7 +496,7 @@ export function GuideImageExport({
               <div
                 ref={previewRef}
                 data-export-language={language}
-                className={cn("dark bg-background p-10 text-foreground", captureClassName)}
+                className={cn("bg-background p-10 text-foreground", captureClassName)}
                 style={{ width, height }}
               >
                 <style>{'[data-export-language="th"] [data-export-lang="en"],[data-export-language="en"] [data-export-lang="th"]{display:none!important}'}</style>
@@ -516,7 +516,7 @@ export function GuideImageExport({
                 ref={captureRef}
                 data-export-language={language}
                 className={cn(
-                  "dark bg-background p-10 text-foreground",
+                  "bg-background p-10 text-foreground",
                   captureClassName,
                 )}
                 style={{ width, height }}
diff --git a/components/public/material-poster.tsx b/components/public/material-poster.tsx
index 496a482..a511b23 100644
--- a/components/public/material-poster.tsx
+++ b/components/public/material-poster.tsx
@@ -121,7 +121,7 @@ export function MaterialPoster({
 
   return (
     <div
-      className={cn("dark @container relative aspect-4/5 w-full select-none overflow-hidden bg-black text-white", interactive && characterArtUrl && "cursor-move", className)}
+      className={cn("@container relative aspect-4/5 w-full select-none overflow-hidden bg-black text-white", interactive && characterArtUrl && "cursor-move", className)}
       style={{ backgroundImage: background }}
       onPointerDown={handlePointerDown}
       onPointerMove={handlePointerMove}
diff --git a/components/public/weapon-image-export.tsx b/components/public/weapon-image-export.tsx
index 9f3e80a..814ee12 100644
--- a/components/public/weapon-image-export.tsx
+++ b/components/public/weapon-image-export.tsx
@@ -64,7 +64,7 @@ export function WeaponComparisonImage({
   const maximum = Math.max(100, ...values);
 
   return (
-    <div className="dark relative isolate w-300 overflow-hidden bg-[#070b20] px-14 pt-10 pb-12 font-heading text-white">
+    <div className="relative isolate w-300 overflow-hidden bg-[#070b20] px-14 pt-10 pb-12 font-heading text-white">
       <GuideExportBranding backgroundUrl={guide.character.splashImageUrl ?? guide.coverUrl} />
       <header className="relative z-10 flex flex-col items-center px-48 text-center drop-shadow-[0_4px_3px_rgba(0,0,0,0.9)]">
         <h2 className="max-w-full text-5xl leading-tight font-bold text-balance">
diff --git a/components/rich-text-content.tsx b/components/rich-text-content.tsx
index 45f0954..20b2671 100644
--- a/components/rich-text-content.tsx
+++ b/components/rich-text-content.tsx
@@ -12,7 +12,7 @@ export function RichTextContent({
 
   return (
     <div
-      className={cn("prose prose-sm dark:prose-invert max-w-none leading-snug [&>p]:m-0", className)}
+      className={cn("prose prose-sm prose-invert max-w-none leading-snug [&>p]:m-0", className)}
       dangerouslySetInnerHTML={{ __html: sanitizeRichTextHtml(html) }}
     />
   );
diff --git a/components/rich-text-editor.tsx b/components/rich-text-editor.tsx
index bad9634..7d1c8bb 100644
--- a/components/rich-text-editor.tsx
+++ b/components/rich-text-editor.tsx
@@ -213,7 +213,7 @@ export function RichTextEditor({
     onUpdate: ({ editor: currentEditor }) => onChange(normalizedEditorHtml(currentEditor)),
     editorProps: {
       attributes: {
-        class: "prose prose-sm dark:prose-invert min-h-28 max-w-none px-3 py-2 leading-snug outline-none [&_.is-editor-empty:first-child]:before:pointer-events-none [&_.is-editor-empty:first-child]:before:float-left [&_.is-editor-empty:first-child]:before:h-0 [&_.is-editor-empty:first-child]:before:text-muted-foreground [&_.is-editor-empty:first-child]:before:content-[attr(data-placeholder)] [&>p]:m-0",
+        class: "prose prose-sm prose-invert min-h-28 max-w-none px-3 py-2 leading-snug outline-none [&_.is-editor-empty:first-child]:before:pointer-events-none [&_.is-editor-empty:first-child]:before:float-left [&_.is-editor-empty:first-child]:before:h-0 [&_.is-editor-empty:first-child]:before:text-muted-foreground [&_.is-editor-empty:first-child]:before:content-[attr(data-placeholder)] [&>p]:m-0",
       },
     },
   });
diff --git a/components/theme-provider.tsx b/components/theme-provider.tsx
deleted file mode 100644
index 51485dd..0000000
--- a/components/theme-provider.tsx
+++ /dev/null
@@ -1,12 +0,0 @@
-"use client";
-
-import { ThemeProvider as NextThemesProvider } from "next-themes";
-import type { ReactNode } from "react";
-
-export function ThemeProvider({ children }: { children: ReactNode }) {
-  return (
-    <NextThemesProvider attribute="class" defaultTheme="system" enableSystem disableTransitionOnChange>
-      {children}
-    </NextThemesProvider>
-  );
-}
diff --git a/components/theme-switcher.tsx b/components/theme-switcher.tsx
deleted file mode 100644
index d78c0ea..0000000
--- a/components/theme-switcher.tsx
+++ /dev/null
@@ -1,31 +0,0 @@
-"use client";
-
-import { MoonIcon, SunIcon, SunMoonIcon } from "lucide-react";
-import { useTheme } from "next-themes";
-import { useSyncExternalStore } from "react";
-
-import { Button } from "@/components/ui/button";
-
-const subscribe = () => () => {};
-const clientSnapshot = () => true;
-const serverSnapshot = () => false;
-
-export function ThemeSwitcher() {
-  const { resolvedTheme, setTheme } = useTheme();
-  const mounted = useSyncExternalStore(subscribe, clientSnapshot, serverSnapshot);
-  const isDark = resolvedTheme === "dark";
-  const label = mounted ? (isDark ? "เปลี่ยนเป็นโหมดสว่าง" : "เปลี่ยนเป็นโหมดมืด") : "เปลี่ยนธีม";
-
-  return (
-    <Button
-      variant="ghost"
-      size="icon"
-      aria-label={label}
-      title={label}
-      disabled={!mounted}
-      onClick={() => setTheme(isDark ? "light" : "dark")}
-    >
-      {!mounted ? <SunMoonIcon /> : isDark ? <SunIcon /> : <MoonIcon />}
-    </Button>
-  );
-}
diff --git a/components/ui/sonner.tsx b/components/ui/sonner.tsx
index ab0b8b9..d3f848c 100644
--- a/components/ui/sonner.tsx
+++ b/components/ui/sonner.tsx
@@ -1,14 +1,12 @@
 "use client"
 
 import { Toaster as Sonner, type ToasterProps } from "sonner"
-import { useTheme } from "next-themes"
 import { CircleCheckIcon, InfoIcon, TriangleAlertIcon, OctagonXIcon, Loader2Icon } from "lucide-react"
 
 const Toaster = ({ ...props }: ToasterProps) => {
-  const { resolvedTheme } = useTheme()
   return (
     <Sonner
-      theme={resolvedTheme === "dark" ? "dark" : "light"}
+      theme="dark"
       className="toaster group"
       icons={{
         success: (
diff --git a/package.json b/package.json
index 707b53c..7774170 100644
--- a/package.json
+++ b/package.json
@@ -52,7 +52,6 @@
     "lucide-react": "^1.35.0",
     "modern-screenshot": "^4.7.0",
     "next": "^16.4.0",
-    "next-themes": "^0.4.6",
     "postgres": "^3.4.9",
     "qrcode": "^1.5.4",
     "radix-ui": "^1.6.7",