JSFiddle - React, Tailwind, and code Playground

HTML

<link rel="stylesheet" href="http://netdna.bootstrapcdn.com/bootstrap/3.0.0/css/bootstrap.min.css">
<div class="container">

    <div class="row">
        <input id="loginButton" class="btn btn-primary" type="button" value="Login | facebook" onclick="authUserX();" style="display: block;"></input>
        <a href="./redirect.php">
            <input id="loginTwitter" class="btn btn-primary" type="button" value="Login | Twitter "></input>
        </a>
    </div>

</div>

CSS

.row
{
    display: block;
width: 100%;
  text-align: center;    
}

.btn {
    display: inline-block !important;
}