testiframe.php
Quell Code
<html> <head> <style> body{ display:flex; flex-direction:column; } header{ height:25vh; background:red; } nav{ height:30px; background:blue; } main{ height:50vh; background:green; } footer{ height:50px; background:yellow; } </style> <body> <header>Header</header> <nav>Navigation</nav> <main>Content</main> <footer>Footer</footer> </body> </html>