Import source: src/context/ThemeContext

Import the existing local project snapshot. This commit organizes existing files; it does not represent newly developed functionality.

src/context/ThemeContext.tsx

@@ -0,0 +1,21 @@
+import { createContext, useContext, useState, useEffect, type ReactNode } from 'react';
+
+interface ThemeCtx { isDark: boolean; toggle: () => void; }
+
+const ThemeContext = createContext<ThemeCtx>({ isDark: true, toggle: () => {} });
+
+export function ThemeProvider({ children }: { children: ReactNode }) {
+  const [isDark, setIsDark] = useState(false);
+
+  useEffect(() => {
+    document.documentElement.setAttribute('data-theme', isDark ? 'dark' : 'light');
+  }, [isDark]);
+
+  return (
+    <ThemeContext.Provider value={{ isDark, toggle: () => setIsDark(d => !d) }}>
+      {children}
+    </ThemeContext.Provider>
+  );
+}
+
+export const useTheme = () => useContext(ThemeContext);