@if (User.Identity.IsAuthenticated)
{
    <form asp-controller="Account" asp-action="Logout" asp-route-returnUrl="@Url.Action("Index", "Home", new { area = "" })" method="post" id="logoutForm" class="navbar-right">
        <ul class="nav navbar-nav navbar-right">
            <li class="navbar-text">Hello @User.Identity.Name!</li>
            <li>
                <button type="submit" class="btn btn-link navbar-btn navbar-link">Log out</button>
            </li>
        </ul>
    </form>
}
else
{
    <ul class="nav navbar-nav navbar-right">
        <li><a asp-controller="Account" asp-action="Login">Login</a></li>
    </ul>
}