Twitter bootstrap class "btn btn-primary" doesn't work with Laravel

I am working on a laravel app, and I want to apply a twitter bootstrap class "btn btn-primary" class. but It's doesn't apply any change on my button.

Firstly as in my mind I should run those two commands and I did that

php artisan install

php artisan dev

My button

<button type="button" class="btn btn-primary" onclick="window.location=''">Button</button>

via Chebli Mohamed