I am new to Angular 4 and started working with the material components, I copied a couple of example from the official documentation but didn't get the same result as the documentation :

How do I get change the textbox width ? I tried style="width: 200px;" style="width:100%"; class="col-md-x" But none of them worked, second thing is how to center that login container in the middle of the page ? I found a few answers here but none of them seems to be working as well, here is my code :
<div class="container">
<div class="row">
<div class="col-md-6 offset-md-3">
<md-card>
<md-card-title>Login</md-card-title>
<md-card-content>
<form class="example-form">
<div>
<md-form-field class="example-full-width">
<input mdInput placeholder="Username" type="text">
</md-form-field>
</div>
<div>
<md-form-field class="example-full-width">
<input mdInput placeholder="Password" type="password">
</md-form-field>
</div>
</form>
</md-card-content>
</md-card>
</div>
</div>
</div>
**