@{
    ViewData["Title"] = "Login";
}

<h2>Login</h2>

<form asp-action="Login" asp-controller="Auth" method="post">
    <div class="form-group">
        <label for="username">Username</label>
        <input type="text" id="username" name="username" class="form-control" />
    </div>
    <div class="form-group">
        <label for="password">Password</label>
        <input type="password" id="password" name="password" class="form-control" />
    </div>
    <button type="submit" class="btn btn-primary">Login</button>
</form>

<div>
    @foreach (var error in ViewData.ModelState.Values.SelectMany(v => v.Errors))
    {
        <p style="color: red;">@error.ErrorMessage</p>
    }
</div>