Text Input with label
To create stylized text input, put your input label and input
element inside a div with class 'input-group'.
<div class="input-group">
<label for="username">Username</label>
<input type="text" class="input" id="username" placeholder="Enter your username" />
<label for="password">Password</label>
<input type="password" class="input" id="password" placeholder="Enter your password" />
</div>