Centering log in grid in my container? - css

Question

I have tried different kinds of approach to center my log-in. I want it to be vertically and horizontally centered in my container. Would appreciate any help! Can someone give me some good idea?
<div class="container login">
<div class="col-md-4 login-centered">
<div class="panel panel-default">
<div class="panel-heading"><h3 class="panel-title"><strong style="color:white">Sign in </strong></h3></div>
<div class="panel-body">
<section role="form">
#using (Html.BeginForm()
{
#Html.AntiForgeryToken()
#Html.ValidationSummary()
<div class="form-group" style="display:block;margin:auto;">
<label>Username</label>
#Html.TextBoxFor()
#Html.ValidationMessageFor()
</div>
<div class="form-group" style="display:block;margin:auto;margin-top:6px;">
<label >Password</label>
#Html.PasswordFor()
#Html.ValidationMessageFor( )
</div>
<input type="submit" value="Log in" class="pull-right btn-sm btn-default" />
}
</section>
</div>
</div>
</div>
</div>
This is my css:
.login-centered {
display:block;
margin-left:auto;
margin-right:auto;
}
.panel-heading {
background-color: #2190b6!important;
}
.btn-default {
background-color: #2190b6 !important;
border: 1px solid #2190b6 !important;
color: #FFF!important;
margin-top: 10px;
}
.btn-default:hover, .btn-default:active:focus{
background-color: #2190b6 !important;
border: 1px solid #2190b6 !important;
color: #FFF!important;
}

Answer 1

The following CSS code should do the job !!
.login-centered {
top: 50%;
left: 50%;
transform: translateX(-50%) translateY(-50%);
position: absolute;
}