<!DOCTYPE html> <html lang="en"> <head> <title>Simple Responsive Flexbox Layout</title> <style> body { font-family: Arial, sans-serif; margin: 0; padding: 0; display: flex; flex-direction: column; height: 100vh; } header, footer { background: #35424a; color: white; text-align: center; padding: 10px 0; } .container { display: flex; flex: 1; /* Take remaining space */ padding: 20px; gap: 20px; /* Space between items */ } main { flex: 3; /* Main content takes more space */ background: white; padding: 20px; border-radius: 5px; } aside { flex: 1; /* Sidebar takes less space */ background: #e7e7e7; padding: 20px; border-radius: 5px; } /* Responsive Styles */ </style> </head> <body> <header> <h1>Responsive Flexbox Layout</h1> </header> <div class="container"> <main> <h2>Main Content</h2> <p>This is the main content area. You can place your articles, images, or other important information here.</p> </main> <aside> <h2>Sidebar</h2> <p>This is a sidebar. You can add additional links, ads, or other content here.</p> </aside> </div> <footer> <p>© 2024 Your Website. All rights reserved.</p> </footer> </body> </html>