<!DOCTYPE html> <html> <head> <meta charset="utf-8"> <meta http-equiv="X-UA-Compatible" content="IE=edge"> <title>Hello World</title> </head> <body>
<h1 class="text-center">helloworld</h1>
<p class="text-center"><button class="btn btn-primary">I'm Button</button></p>
</body> </html>
