diff --git a/components/log-viewer-webui/client/src/AntdApp.tsx b/components/log-viewer-webui/client/src/AntdApp.tsx
index 5435bae9d9..28de5c877f 100644
--- a/components/log-viewer-webui/client/src/AntdApp.tsx
+++ b/components/log-viewer-webui/client/src/AntdApp.tsx
@@ -1,6 +1,9 @@
 import {RouterProvider} from "react-router";
 
+import {ConfigProvider} from "antd";
+
 import router from "./router";
+import THEME_CONFIG, {useThemeStore} from "./theme";
 
 import "@ant-design/v5-patch-for-react-19";
 
@@ -11,7 +14,18 @@ import "@ant-design/v5-patch-for-react-19";
  * @return
  */
 const AntApp = () => {
-    return <RouterProvider router={router}/>;
+    const {algorithm} = useThemeStore();
+
+    return (
+        <ConfigProvider
+            theme={{
+                ...THEME_CONFIG,
+                algorithm: algorithm,
+            }}
+        >
+            <RouterProvider router={router}/>
+        </ConfigProvider>
+    );
 };
 
 export default AntApp;
diff --git a/components/log-viewer-webui/client/src/components/Layout/MainLayout.module.css b/components/log-viewer-webui/client/src/components/Layout/MainLayout.module.css
index 784310750a..05a29739fa 100644
--- a/components/log-viewer-webui/client/src/components/Layout/MainLayout.module.css
+++ b/components/log-viewer-webui/client/src/components/Layout/MainLayout.module.css
@@ -1,5 +1,6 @@
 .mainLayout {
-  min-height: 100vh;
+  height: 100vh;
+  overflow: hidden;
 }
 
 .siderLogoContainer {
@@ -9,8 +10,20 @@
   height: 64px;
 }
 
+.siderContainer {
+  flex-direction: column;
+  display: flex;
+  justify-content: space-between;
+  height: 100%;
+}
+
 .siderLogo {
   max-width: 100%;
   max-height: 100%;
-  height: 32px;
+  padding-inline: 10%;
+  padding-block: 16px;
+}
+
+.siderTopMenu {
+  flex-grow: 1;
 }
diff --git a/components/log-viewer-webui/client/src/components/Layout/MainLayout.tsx b/components/log-viewer-webui/client/src/components/Layout/MainLayout.tsx
index b3ef4f89c5..26778e0b5b 100644
--- a/components/log-viewer-webui/client/src/components/Layout/MainLayout.tsx
+++ b/components/log-viewer-webui/client/src/components/Layout/MainLayout.tsx
@@ -1,7 +1,7 @@
-import {useState} from "react";
 import {
     Link,
     Outlet,
+    useLocation,
 } from "react-router";
 
 import {
@@ -15,45 +15,57 @@ import {
 } from "antd";
 
 import styles from "./MainLayout.module.css";
+import ThemeToggleMenuItem from "./ThemeToggleMenuItem";
 
 
 const {Sider} = Layout;
 
 type MenuItem = Required<MenuProps>["items"][number];
 
-const SIDEBAR_MENU_ITEMS: MenuItem[] = [
+const sidebarTopMenuItems: MenuItem[] = [
+    {type: "divider"},
     {label: <Link to={"/ingest"}>Ingest</Link>, key: "/ingest", icon: <UploadOutlined/>},
     {label: <Link to={"/search"}>Search</Link>, key: "/search", icon: <SearchOutlined/>},
 ];
 
+const sidebarBottomMenuItems = [
+    <ThemeToggleMenuItem key={"theme-toggle"}/>,
+];
+
 /**
  * The main layout of web ui.
  *
  * @return
  */
 const MainLayout = () => {
-    const [collapsed, setCollapsed] = useState(false);
+    const {pathname} = useLocation();
 
     return (
         <Layout className={styles["mainLayout"]}>
             <Sider
-                collapsed={collapsed}
+                collapsedWidth={50}
                 collapsible={true}
                 theme={"light"}
-                width={"150"}
-                onCollapse={(value) => {
-                    setCollapsed(value);
-                }}
+                width={"200"}
             >
-                <div className={styles["siderLogoContainer"]}>
-                    <img
-                        alt={"CLP Logo"}
-                        className={styles["siderLogo"]}
-                        src={"/clp-logo.png"}/>
+                <div className={styles["siderContainer"]}>
+                    <div className={styles["siderLogoContainer"]}>
+                        <img
+                            alt={"CLP Logo"}
+                            className={styles["siderLogo"]}
+                            src={"/clp-logo.png"}/>
+                    </div>
+                    <Menu
+                        className={styles["siderTopMenu"]}
+                        items={sidebarTopMenuItems}
+                        selectedKeys={[pathname]}/>
+                    <Menu
+                        selectable={false}
+                        selectedKeys={[]}
+                    >
+                        {sidebarBottomMenuItems}
+                    </Menu>
                 </div>
-                <Menu
-                    items={SIDEBAR_MENU_ITEMS}
-                    mode={"inline"}/>
             </Sider>
             <Layout>
                 <Outlet/>
diff --git a/components/log-viewer-webui/client/src/components/Layout/ThemeToggleMenuItem.tsx b/components/log-viewer-webui/client/src/components/Layout/ThemeToggleMenuItem.tsx
new file mode 100644
index 0000000000..07b64f7760
--- /dev/null
+++ b/components/log-viewer-webui/client/src/components/Layout/ThemeToggleMenuItem.tsx
@@ -0,0 +1,66 @@
+import {useCallback} from "react";
+
+import {
+    FormatPainterOutlined,
+    MoonOutlined,
+    SunOutlined,
+} from "@ant-design/icons";
+import {Menu} from "antd";
+
+import {
+    THEME_MODE,
+    useThemeStore,
+} from "../../theme";
+
+
+/**
+ * Maps theme mode to icon.
+ */
+const THEME_MODE_TO_ICON: Record<THEME_MODE, React.ReactNode> = Object.freeze({
+    [THEME_MODE.SYSTEM]: <FormatPainterOutlined/>,
+    [THEME_MODE.DARK]: <MoonOutlined/>,
+    [THEME_MODE.LIGHT]: <SunOutlined/>,
+});
+
+/**
+ * Maps theme mode to label.
+ */
+const THEME_MODE_TO_LABEL: Record<THEME_MODE, string> = Object.freeze({
+    [THEME_MODE.SYSTEM]: "System",
+    [THEME_MODE.DARK]: "Dark",
+    [THEME_MODE.LIGHT]: "Light",
+});
+
+const {Item} = Menu;
+
+/**
+ * Displays a theme toggle menu item.
+ *
+ * @return
+ */
+const ThemeToggleMenuItem = () => {
+    const mode = useThemeStore((state) => state.mode);
+
+    const handleClick = useCallback(() => {
+        const {setMode} = useThemeStore.getState();
+        if (mode === THEME_MODE.SYSTEM) {
+            setMode(THEME_MODE.DARK);
+        } else if (mode === THEME_MODE.DARK) {
+            setMode(THEME_MODE.LIGHT);
+        } else {
+            setMode(THEME_MODE.SYSTEM);
+        }
+    }, [mode]);
+
+    return (
+        <Item
+            icon={THEME_MODE_TO_ICON[mode]}
+            onClick={handleClick}
+        >
+            {THEME_MODE_TO_LABEL[mode]}
+        </Item>
+    );
+};
+
+
+export default ThemeToggleMenuItem;
diff --git a/components/log-viewer-webui/client/src/theme/index.tsx b/components/log-viewer-webui/client/src/theme/index.tsx
new file mode 100644
index 0000000000..18fa69f625
--- /dev/null
+++ b/components/log-viewer-webui/client/src/theme/index.tsx
@@ -0,0 +1,25 @@
+import type {ThemeConfig} from "antd/es/config-provider/context";
+
+import useThemeStore from "./themeStore";
+import {THEME_MODE} from "./typings";
+
+
+/**
+ * Ant Design theme configuration.
+ */
+const THEME_CONFIG: ThemeConfig = Object.freeze({
+    token: {
+        fontFamily: "'Inter', sans-serif",
+        colorPrimary: "#2a8efa",
+        borderRadius: 3,
+    },
+    cssVar: true,
+    hashed: false,
+});
+
+
+export {
+    THEME_MODE,
+    useThemeStore,
+};
+export default THEME_CONFIG;
diff --git a/components/log-viewer-webui/client/src/theme/themeStore.ts b/components/log-viewer-webui/client/src/theme/themeStore.ts
new file mode 100644
index 0000000000..ad28f82b05
--- /dev/null
+++ b/components/log-viewer-webui/client/src/theme/themeStore.ts
@@ -0,0 +1,56 @@
+import type {MappingAlgorithm} from "antd/es/theme/interface";
+import {create} from "zustand";
+import {persist} from "zustand/middleware";
+
+import {THEME_MODE} from "./typings";
+import {
+    getAlgorithm,
+    getSystemAlgorithm,
+} from "./utils";
+
+
+interface ThemeValues {
+    algorithm: MappingAlgorithm;
+    mode: THEME_MODE;
+}
+
+interface ThemeActions {
+    setMode: (mode: THEME_MODE) => void;
+}
+
+type ThemeState = ThemeValues & ThemeActions;
+
+const THEME_DEFAULT: ThemeValues = {
+    algorithm: getSystemAlgorithm(),
+    mode: THEME_MODE.SYSTEM,
+};
+
+const useThemeStore = create(
+    persist<ThemeState>(
+        (set) => ({
+            ...THEME_DEFAULT,
+            setMode: (newMode: THEME_MODE) => {
+                set({mode: newMode});
+                set({algorithm: getAlgorithm(newMode)});
+            },
+        }),
+        {
+            name: "theme-storage",
+            merge: (persistedState, currentState) => {
+                const safePersistedState = persistedState as Partial<ThemeState>;
+
+                return {
+                    ...currentState,
+                    ...safePersistedState,
+                    ...(
+                        safePersistedState.mode &&
+                        {algorithm: getAlgorithm(safePersistedState.mode)}
+                    ),
+                };
+            },
+        }
+    )
+);
+
+
+export default useThemeStore;
diff --git a/components/log-viewer-webui/client/src/theme/typings.ts b/components/log-viewer-webui/client/src/theme/typings.ts
new file mode 100644
index 0000000000..548dc6e959
--- /dev/null
+++ b/components/log-viewer-webui/client/src/theme/typings.ts
@@ -0,0 +1,8 @@
+enum THEME_MODE {
+    SYSTEM = "system",
+    DARK = "dark",
+    LIGHT = "light",
+}
+
+
+export {THEME_MODE};
diff --git a/components/log-viewer-webui/client/src/theme/utils.ts b/components/log-viewer-webui/client/src/theme/utils.ts
new file mode 100644
index 0000000000..0f6215b6ed
--- /dev/null
+++ b/components/log-viewer-webui/client/src/theme/utils.ts
@@ -0,0 +1,37 @@
+import {theme} from "antd";
+
+import {THEME_MODE} from "./typings";
+
+
+/**
+ * Detects Antd theme algorithm from system theme.
+ *
+ * @return The system theme algorithm.
+ */
+const getSystemAlgorithm = () => {
+    return window.matchMedia("(prefers-color-scheme: dark)").matches ?
+        theme.darkAlgorithm :
+        theme.defaultAlgorithm;
+};
+
+/**
+ * Detects Antd theme algorithm for the given theme mode.
+ *
+ * @param mode
+ * @return The theme algorithm.
+ */
+const getAlgorithm = (mode: THEME_MODE) => {
+    if (mode === THEME_MODE.SYSTEM) {
+        return getSystemAlgorithm();
+    } else if (mode === THEME_MODE.DARK) {
+        return theme.darkAlgorithm;
+    }
+
+    return theme.defaultAlgorithm;
+};
+
+
+export {
+    getAlgorithm,
+    getSystemAlgorithm,
+};