feat: Implement dark mode theme support across components

- Added ThemeContext for managing theme state and toggling between light and dark modes.
- Updated components (EntrepreneurshipSection, Footer, HeroSection, LeadershipSection, ReviewSection, TechSection, UniqueSection) to utilize theme context and apply conditional styling based on the current theme.
- Enhanced CSS with custom properties for theming and transitions.
- Configured Tailwind CSS to support dark mode.
- Ensured consistent styling and transitions for text and background colors in dark mode.

tailwind.config.js

@@ -0,0 +1,7 @@
+export default {
+  darkMode: 'class',
+  content: [
+    "./index.html",
+    "./src/**/*.{js,ts,jsx,tsx}",
+  ],
+}