.login-body {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
    display: flex;
    align-items: center;
}

.login-card {
    background: white;
    border-radius: 15px;
    box-shadow: 0 10px 30px rgba(0,0,0,0.2);
    overflow: hidden;
}

.card-header {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 2rem 1rem;
}

.card-header h4 {
    font-weight: 300;
}

.card-body {
    padding: 2rem;
}

.btn-primary {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    border: none;
    padding: 0.75rem;
}

.btn-primary:hover {
    background: linear-gradient(135deg, #5a6fd8 0%, #6a4190 100%);
    transform: translateY(-1px);
    box-shadow: 0 5px 15px rgba(0,0,0,0.2);
}

.form-control:focus {
    border-color: #667eea;
    box-shadow: 0 0 0 0.2rem rgba(102, 126, 234, 0.25);
}
/* Estilos para validación */
.is-valid {
    border-color: #198754 !important;
}

.is-invalid {
    border-color: #dc3545 !important;
}

/* Transiciones suaves */
.login-card {
    transition: all 0.3s ease;
}

#systemSelection {
    transition: all 0.3s ease-in-out;
}

/* Mejora visual para los selects */
.form-select:focus {
    border-color: #667eea;
    box-shadow: 0 0 0 0.2rem rgba(102, 126, 234, 0.25);
}

/* Animación para mostrar/ocultar elementos */
.fade-in {
    animation: fadeIn 0.3s ease-in;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(-10px); }
    to { opacity: 1; transform: translateY(0); }
}