diff --git a/theme-test.tsx b/theme-test.tsx
new file mode 100644
index 00000000..16559bf7
--- /dev/null
+++ b/theme-test.tsx
@@ -0,0 +1,285 @@
+import React, { useState, useEffect, useCallback, useMemo } from "react"
+import { ComponentType, FC, ReactNode, JSX } from "react"
+
+// Interface definitions
+interface User {
+  id: number
+  name: string
+  email?: string
+  readonly createdAt: Date
+  active: boolean
+}
+
+type Theme = "light" | "dark" | "auto"
+type Status = "pending" | "loading" | "success" | "error"
+
+// Generic function with constraints
+function createRepository<T extends { id: number }>(items: T[]): Repository<T> {
+  return new Repository(items)
+}
+
+// Class definition
+class Repository<T> {
+  private items: T[]
+  protected cache: Map<string, T>
+
+  constructor(items: T[] = []) {
+    this.items = items
+    this.cache = new Map()
+  }
+
+  public find(id: number): T | undefined {
+    return this.items.find((item) => item.id === id)
+  }
+
+  public async findAll(): Promise<T[]> {
+    return this.items
+  }
+
+  get count(): number {
+    return this.items.length
+  }
+}
+
+// Enum definition
+enum LogLevel {
+  DEBUG = 0,
+  INFO = 1,
+  WARN = 2,
+  ERROR = 3,
+}
+
+// Constants
+const API_URL = "https://api.example.com"
+const MAX_RETRIES = 3
+const DEFAULT_TIMEOUT = 5000
+
+// Regular expressions
+const EMAIL_REGEX = /^[a-zA-Z0-9._%+-]+@[a-zA-Z0-9.-]+\.[a-zA-Z]{2,}$/
+const PHONE_REGEX = /^\+?1?-?\.?\s?\(?(\d{3})\)?[-.\s]?(\d{3})[-.\s]?(\d{4})$/
+
+// Template literals
+const greeting = `Hello, ${user.name}!`
+const sql = `
+  SELECT * FROM users 
+  WHERE active = true 
+  AND created_at > '${new Date().toISOString()}'
+`
+
+// Arrow functions
+const debounce = <T extends (...args: any[]) => any>(
+  func: T,
+  wait: number,
+): ((...args: Parameters<T>) => void) => {
+  let timeout: NodeJS.Timeout
+  return (...args: Parameters<T>) => {
+    clearTimeout(timeout)
+    timeout = setTimeout(() => func(...args), wait)
+  }
+}
+
+// Async function
+async function fetchUserData(userId: number): Promise<User> {
+  try {
+    const response = await fetch(`${API_URL}/users/${userId}`)
+    if (!response.ok) {
+      throw new Error(`HTTP error! status: ${response.status}`)
+    }
+    return await response.json()
+  } catch (error) {
+    console.error("Failed to fetch user data:", error)
+    throw error
+  }
+}
+
+// React component with various patterns
+const ThemeProvider: FC<{ children: ReactNode; theme?: Theme }> = ({
+  children,
+  theme = "auto",
+}) => {
+  const [currentTheme, setCurrentTheme] = useState<Theme>(theme)
+  const [status, setStatus] = useState<Status>("pending")
+
+  useEffect(() => {
+    const mediaQuery = window.matchMedia("(prefers-color-scheme: dark)")
+    const handleChange = (e: MediaQueryListEvent) => {
+      setCurrentTheme(e.matches ? "dark" : "light")
+    }
+
+    mediaQuery.addEventListener("change", handleChange)
+    return () => mediaQuery.removeEventListener("change", handleChange)
+  }, [])
+
+  const contextValue = useMemo(
+    () => ({
+      theme: currentTheme,
+      setTheme: setCurrentTheme,
+      toggleTheme: () => setCurrentTheme((prev) => (prev === "light" ? "dark" : "light")),
+    }),
+    [currentTheme],
+  )
+
+  return (
+    <ThemeContext.Provider value={contextValue}>
+      <div className={`theme-${currentTheme}`} data-theme={currentTheme}>
+        {children}
+      </div>
+    </ThemeContext.Provider>
+  )
+}
+
+// Higher-order component
+function withLogging<P extends object>(Component: ComponentType<P>): ComponentType<P> {
+  return function LoggedComponent(props: P) {
+    console.log("Rendering component:", Component.name)
+    return <Component {...props} />
+  }
+}
+
+// Custom hook
+function useLocalStorage<T>(key: string, initialValue: T): [T, (value: T) => void] {
+  const [storedValue, setStoredValue] = useState<T>(() => {
+    try {
+      const item = window.localStorage.getItem(key)
+      return item ? JSON.parse(item) : initialValue
+    } catch (error) {
+      console.warn(`Error reading localStorage key "${key}":`, error)
+      return initialValue
+    }
+  })
+
+  const setValue = useCallback(
+    (value: T) => {
+      try {
+        setStoredValue(value)
+        window.localStorage.setItem(key, JSON.stringify(value))
+      } catch (error) {
+        console.warn(`Error setting localStorage key "${key}":`, error)
+      }
+    },
+    [key],
+  )
+
+  return [storedValue, setValue]
+}
+
+// JSX component with various elements
+const UserProfile: FC<{ user: User; onUpdate?: (user: User) => void }> = ({ user, onUpdate }) => {
+  const [isEditing, setIsEditing] = useState(false)
+  const [formData, setFormData] = useState(user)
+  const [errors, setErrors] = useState<Record<string, string>>({})
+
+  const handleSubmit = async (e: React.FormEvent) => {
+    e.preventDefault()
+
+    // Validation
+    if (!formData.name.trim()) {
+      setErrors({ name: "Name is required" })
+      return
+    }
+
+    if (formData.email && !EMAIL_REGEX.test(formData.email)) {
+      setErrors({ email: "Invalid email format" })
+      return
+    }
+
+    try {
+      setStatus("loading")
+      await onUpdate?.(formData)
+      setStatus("success")
+      setIsEditing(false)
+    } catch (error) {
+      setStatus("error")
+      setErrors({ submit: "Failed to update profile" })
+    }
+  }
+
+  return (
+    <div className="user-profile">
+      <div className="user-header">
+        <h2>{user.name}</h2>
+        <span className={`status status-${user.active ? "active" : "inactive"}`}>
+          {user.active ? "Active" : "Inactive"}
+        </span>
+      </div>
+
+      {isEditing ? (
+        <form onSubmit={handleSubmit} className="user-form">
+          <div className="form-group">
+            <label htmlFor="name">Name:</label>
+            <input
+              id="name"
+              type="text"
+              value={formData.name}
+              onChange={(e) => setFormData({ ...formData, name: e.target.value })}
+              className={errors.name ? "error" : ""}
+              placeholder="Enter your name"
+              required
+            />
+            {errors.name && <span className="error-message">{errors.name}</span>}
+          </div>
+
+          <div className="form-group">
+            <label htmlFor="email">Email:</label>
+            <input
+              id="email"
+              type="email"
+              value={formData.email || ""}
+              onChange={(e) => setFormData({ ...formData, email: e.target.value })}
+              className={errors.email ? "error" : ""}
+              placeholder="user@example.com"
+            />
+            {errors.email && <span className="error-message">{errors.email}</span>}
+          </div>
+
+          <div className="form-actions">
+            <button type="submit" disabled={status === "loading"}>
+              {status === "loading" ? "Saving..." : "Save"}
+            </button>
+            <button type="button" onClick={() => setIsEditing(false)} className="secondary">
+              Cancel
+            </button>
+          </div>
+
+          {errors.submit && <div className="alert alert-error">{errors.submit}</div>}
+        </form>
+      ) : (
+        <div className="user-details">
+          <p>
+            <strong>ID:</strong> {user.id}
+          </p>
+          <p>
+            <strong>Email:</strong> {user.email || "Not provided"}
+          </p>
+          <p>
+            <strong>Member since:</strong> {user.createdAt.toLocaleDateString()}
+          </p>
+
+          <button onClick={() => setIsEditing(true)} className="edit-button">
+            Edit Profile
+          </button>
+        </div>
+      )}
+    </div>
+  )
+}
+
+// Export statements
+export {
+  User,
+  Theme,
+  Status,
+  LogLevel,
+  Repository,
+  ThemeProvider,
+  UserProfile,
+  fetchUserData,
+  useLocalStorage,
+  withLogging,
+  debounce,
+}
+
+export default ThemeProvider
+
+// Type exports
+export type { User as UserType, ComponentType as ReactComponentType }