}

<link href="/Content/bs3/css/bootstrap.min.css" rel="stylesheet" />
<link href="/Content/css/style-responsive.css" rel="stylesheet" />
<link href="/Content/css/atom-style.css" rel="stylesheet" />
<link href="/Content/css/font-awesome.min.css" rel="stylesheet" />
<link href="/Content/css/animate.css" rel="stylesheet" />

<form action="/Login/Login" class="login-form-signin" method="post" name="forma">    <div class="login-logo">
        <img src="/Images/logo.png">
    </div>
    <h2 class="login-form-signin-heading">INGRESA TUS CREDENCIALES</h2>
    <div class="login-wrap">

                <input type="text" autofocus placeholder="Nombre" class="form-control" name="UserName" value="">
                <input type="password" placeholder="Password" class="form-control" name="Password" autocomplete="on" onkeypress="return entsub(this.form)" value="">
            <!-- Campo OTP oculto por defecto -->
            <div id="otpContainer"
                 style="display:none; margin-top:10px;">
                <input type="text" placeholder="Código de autenticación"
                       class="form-control"
                       name="OtpCode"
                       id="OtpCode">
            </div>
            <button type="button" id="btnLogin" name="LOGIN" class="btn btn-lg btn-primary btn-block" onclick="logIn()">
Ingresar            </button>


        <!-- Mostrar errores -->

    </div>
<input name="__RequestVerificationToken" type="hidden" value="CfDJ8CJqK4aN3gFHsAOhCqL10W82LSn6DJzOh2pbKm1_WYVghGAM-YlPrvc4QqezXw_2RqF96SMkkoWj6FeTrRgf8xhwf8RxTZOSCgpxYF33ncqCuuKmkZdVjEJD_cpYN3blxYXNSvWyY1WJo2zBnI-xKkk" /></form>    <script>
        var require2FA = false;

        if (require2FA === "true") {
        console.log("Requiere 2FA", require2FA);
            var otpContainer = document.getElementById("otpContainer");
            if (otpContainer) otpContainer.style.display = "block";

            var btn = document.getElementById("btnLogin");
            if (btn) btn.innerText = "Validar código";

            var otpInput = document.getElementById("OtpCode");
            if (otpInput) otpInput.focus();
        }

        function logIn() {
            //alert("logIn");
            var ok = "";
            if (ok == "" && document.forma.UserName.value == "") { alert("CAPTURE Nombre"); document.forma.UserName.focus(); ok = "1"; }
            if (!require2FA && ok == "" && document.forma.Password.value == "") { alert("CAPTURE Password"); document.forma.Password.focus(); ok = "1"; }

            console.log("requiere 2FA", require2FA);

            // Validar OTP si ya estamos en segundo paso
            // if (require2FA) {
            //     var otp = document.getElementById("OtpCode").value;

            //     if (otp == "") {
            //         alert("Ingrese el código de autenticación");
            //         document.getElementById("OtpCode").focus();
            //         return;
            //     }
            // }

            if (ok == "") {
                document.forma.LOGIN.disabled = true;
                document.forma.submit();
            }

        }

        function entsub(myform) {
            if (window.event && window.event.keyCode == 13)
            {
                logIn();
                return false;
            }
            else
                return true;
        }

        function activar2FA() {
            require2FA = true;

            // Mostrar campo OTP
            var otpContainer = document.getElementById("otpContainer");
            if (otpContainer)
                otpContainer.style.display = "block";

            // Cambiar botón
            var btn = document.getElementById("btnLogin");
            if (btn)
                btn.innerText = "Validar código";

            // Opcional: enfocar OTP
            var otpInput = document.getElementById("OtpCode");
            if (otpInput)
                otpInput.focus();
        }

    </script>