/* === Breakpoints universales === */
@media (max-width: 768px) {
    .page-title { font-size: 1.6rem; }
    .container { padding: 1rem; }
    .form-grid { gap: 10px; }
    .form-control { height: 40px; font-size: 0.95rem; }
    .btn { padding: 8px 14px; font-size: 0.9rem; }
}
@media (max-width: 520px) {
    .page-title { font-size: 1.35rem; }
    .form-grid { display: block; }
    .card { border-radius: 12px; }
}
body {
    background-image: url('../img/3.png');
    background-size: cover;
    background-position: center;
    background-attachment: fixed;
    background-color: #1a1a1a;
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    position: relative;
}
body::before {
    content: '';
    position: absolute;
    inset: 0;
    background-color: rgba(0, 0, 0, 0.4);
    z-index: 0;
}
.register-card {
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(15px);
    border-radius: 1.5rem;
    box-shadow: 0 8px 32px rgba(0, 77, 64, 0.3);
    border: 1px solid rgba(255, 255, 255, 0.5);
    padding: 2.5rem 2rem;
    max-width: 400px;
    width: 100%;
    position: relative;
    z-index: 1;
}
/* ======================================================= */
/* ===  REGISTRO MÓVIL: DISEÑO "DARK GLASS" (MODO OSCURO) === */
/* ======================================================= */

@media screen and (max-width: 768px) {

    /* 1. FONDO OSCURO */
    body {
        justify-content: center !important;
        padding: 20px !important;
        background-attachment: fixed !important;
        background-color: rgba(0, 0, 0, 0.7) !important;
        background-blend-mode: darken !important;
    }

    /* 2. TARJETA DE REGISTRO (CRISTAL OSCURO) */
    .register-card {
        width: 100% !important;
        max-width: 100% !important;
        margin: 0 !important;
        padding: 30px 20px !important;
        border-radius: 25px !important;
        
        /* Fondo Negro/Gris profundo semitransparente */
        background: rgba(30, 30, 30, 0.85) !important;
        backdrop-filter: blur(15px) !important;
        -webkit-backdrop-filter: blur(15px) !important;
        
        border: 1px solid rgba(255, 255, 255, 0.1) !important;
        box-shadow: 0 25px 50px rgba(0, 0, 0, 0.6) !important;
        color: #fff !important; /* Texto blanco general */
    }

    /* Título "Registro" */
    .register-card h2 {
        color: #ffffff !important;
        font-weight: 800 !important;
        font-size: 1.8rem !important;
        margin-bottom: 1.5rem !important;
        text-shadow: 0 2px 10px rgba(0,0,0,0.5) !important;
    }

    /* 3. INPUTS DARK MODE */
    .form-label {
        color: #80cbc4 !important; /* Teal claro */
        font-weight: 700 !important;
        font-size: 0.9rem !important;
        margin-left: 10px !important;
        text-transform: uppercase !important;
        letter-spacing: 0.5px !important;
    }

    .form-control {
        height: 50px !important;
        border-radius: 50px !important;
        background-color: #121212 !important; /* Casi negro */
        border: 1px solid #333 !important;
        padding-left: 20px !important;
        font-size: 1rem !important;
        color: #fff !important;
        box-shadow: inset 0 2px 5px rgba(0,0,0,0.5) !important;
    }

    .form-control:focus {
        background-color: #000 !important;
        border-color: #00bcd4 !important; /* Borde Cian Brillante */
        box-shadow: 0 0 15px rgba(0, 188, 212, 0.3) !important;
    }

    /* Ojito de contraseña */
    .password-toggle {
        color: #80cbc4 !important;
        right: 15px !important;
        font-size: 1.1rem !important;
    }
    
    /* Espacio para el ojito en el input */
    .password-field .form-control {
        padding-right: 50px !important; 
    }

    /* Mensajes de error (Invalid feedback) */
    .invalid-feedback {
        font-size: 0.85rem !important;
        color: #ff5252 !important; /* Rojo brillante para que se vea en oscuro */
        margin-left: 15px !important;
        margin-top: 5px !important;
    }

    /* 4. BOTÓN "REGISTRARSE" (NEÓN VERDE/TEAL) */
    .btn-success {
        width: 100% !important;
        height: 55px !important;
        border-radius: 50px !important;
        /* Degradado Verde a Teal */
        background: linear-gradient(135deg, #009688 0%, #2e7d32 100%) !important;
        border: none !important;
        font-size: 1.1rem !important;
        font-weight: 800 !important;
        text-transform: uppercase;
        letter-spacing: 1px;
        box-shadow: 0 0 20px rgba(0, 150, 136, 0.4) !important;
        margin-top: 10px !important;
    }
    
    .btn-success:hover, .btn-success:active {
        transform: scale(0.98) !important;
        background: linear-gradient(135deg, #2e7d32 0%, #009688 100%) !important;
    }

    /* 5. ENLACE "INICIA SESIÓN AQUÍ" */
    .text-muted { color: #b0bec5 !important; font-size: 0.9rem !important; }
    .text-primary { 
        color: #4dd0e1 !important; /* Cian claro */
        font-weight: 700 !important; 
        text-decoration: none !important;
        margin-left: 5px !important;
    }
}