diff --git a/web/src/components/AuthFooter.tsx b/web/src/components/AuthFooter.tsx
index 6553af5bc..0ad7b4ff4 100644
--- a/web/src/components/AuthFooter.tsx
+++ b/web/src/components/AuthFooter.tsx
@@ -1,6 +1,8 @@
 import { observer } from "mobx-react-lite";
+import { useState } from "react";
 import { cn } from "@/lib/utils";
 import { workspaceStore } from "@/store";
+import { loadTheme } from "@/utils/theme";
 import LocaleSelect from "./LocaleSelect";
 import ThemeSelect from "./ThemeSelect";
 
@@ -9,10 +11,22 @@ interface Props {
 }
 
 const AuthFooter = observer(({ className }: Props) => {
+  // Local state for login page theme since we can't persist to server
+  const [localTheme, setLocalTheme] = useState(workspaceStore.state.theme || "default");
+
+  const handleThemeChange = (theme: string) => {
+    // Update local state
+    setLocalTheme(theme);
+    // Update workspace store for immediate UI feedback
+    workspaceStore.state.setPartial({ theme });
+    // Apply theme to DOM
+    loadTheme(theme);
+  };
+
   return (
     <div className={cn("mt-4 flex flex-row items-center justify-center w-full gap-2", className)}>
       <LocaleSelect value={workspaceStore.state.locale} onChange={(locale) => workspaceStore.state.setPartial({ locale })} />
-      <ThemeSelect value={workspaceStore.state.theme} onValueChange={(theme) => workspaceStore.state.setPartial({ theme })} />
+      <ThemeSelect value={localTheme} onValueChange={handleThemeChange} />
     </div>
   );
 });
diff --git a/web/src/components/Settings/PreferencesSection.tsx b/web/src/components/Settings/PreferencesSection.tsx
index 978343e74..df237e023 100644
--- a/web/src/components/Settings/PreferencesSection.tsx
+++ b/web/src/components/Settings/PreferencesSection.tsx
@@ -47,7 +47,10 @@ const PreferencesSection = observer(() => {
       </div>
 
       <div className="w-full flex flex-row justify-between items-center">
-        <span>{t("setting.preference-section.theme")}</span>
+        <div className="flex flex-col">
+          <span>{t("setting.preference-section.theme")}</span>
+          <span className="text-xs text-muted-foreground">Your personal theme preference (overrides default)</span>
+        </div>
         <ThemeSelect value={setting.theme} onValueChange={handleThemeChange} />
       </div>
 
diff --git a/web/src/components/Settings/WorkspaceSection.tsx b/web/src/components/Settings/WorkspaceSection.tsx
index 6d0830812..d44052a91 100644
--- a/web/src/components/Settings/WorkspaceSection.tsx
+++ b/web/src/components/Settings/WorkspaceSection.tsx
@@ -81,7 +81,10 @@ const WorkspaceSection = observer(() => {
       <Separator />
       <p className="font-medium text-foreground">{t("setting.system-section.title")}</p>
       <div className="w-full flex flex-row justify-between items-center">
-        <span>Theme</span>
+        <div className="flex flex-col">
+          <span>Default Theme</span>
+          <span className="text-xs text-muted-foreground">Sets the default theme for all users</span>
+        </div>
         <ThemeSelect
           value={workspaceGeneralSetting.theme || "default"}
           onValueChange={(value: string) => updatePartialSetting({ theme: value })}
diff --git a/web/src/components/ThemeSelect.tsx b/web/src/components/ThemeSelect.tsx
index 3e0a1a4e2..24d69eb7c 100644
--- a/web/src/components/ThemeSelect.tsx
+++ b/web/src/components/ThemeSelect.tsx
@@ -1,12 +1,14 @@
+import { observer } from "mobx-react-lite";
 import { Moon, Palette, Sun, Wallpaper } from "lucide-react";
 import { Select, SelectContent, SelectItem, SelectTrigger, SelectValue } from "@/components/ui/select";
-import { workspaceStore } from "@/store";
+import { workspaceStore, userStore } from "@/store";
 import { THEME_OPTIONS } from "@/utils/theme";
 
 interface ThemeSelectProps {
   value?: string;
   onValueChange?: (theme: string) => void;
   className?: string;
+  showEffectiveTheme?: boolean;
 }
 
 const THEME_ICONS: Record<string, JSX.Element> = {
@@ -16,8 +18,13 @@ const THEME_ICONS: Record<string, JSX.Element> = {
   whitewall: <Wallpaper className="w-4 h-4" />,
 };
 
-const ThemeSelect = ({ value, onValueChange, className }: ThemeSelectProps = {}) => {
+const ThemeSelect = observer(({ value, onValueChange, className, showEffectiveTheme = false }: ThemeSelectProps = {}) => {
   const currentTheme = value || workspaceStore.state.theme || "default";
+  
+  // Calculate effective theme (user preference overrides workspace default)
+  const effectiveTheme = userStore.state.userGeneralSetting?.theme || workspaceStore.state.theme || "default";
+  
+  const displayTheme = showEffectiveTheme ? effectiveTheme : currentTheme;
 
   const handleThemeChange = (newTheme: Theme) => {
     if (onValueChange) {
@@ -32,6 +39,9 @@ const ThemeSelect = ({ value, onValueChange, className }: ThemeSelectProps = {})
       <SelectTrigger className={className}>
         <div className="flex items-center gap-2">
           <SelectValue placeholder="Select theme" />
+          {showEffectiveTheme && effectiveTheme !== currentTheme && (
+            <span className="text-xs text-muted-foreground">(effective: {effectiveTheme})</span>
+          )}
         </div>
       </SelectTrigger>
       <SelectContent>
@@ -40,12 +50,15 @@ const ThemeSelect = ({ value, onValueChange, className }: ThemeSelectProps = {})
             <div className="flex items-center gap-2">
               {THEME_ICONS[option.value]}
               <span>{option.label}</span>
+              {showEffectiveTheme && option.value === effectiveTheme && (
+                <span className="text-xs text-green-600">✓</span>
+              )}
             </div>
           </SelectItem>
         ))}
       </SelectContent>
     </Select>
   );
-};
+});
 
 export default ThemeSelect;