html {
  font-size: 14px;
}

@media (min-width: 768px) {
  html {
    font-size: 16px;
  }
}

.btn:focus, .btn:active:focus, .btn-link.nav-link:focus, .form-control:focus, .form-check-input:focus {
  box-shadow: 0 0 0 0.1rem white, 0 0 0 0.25rem #258cfb;
}

html {
  position: relative;
  min-height: 100%;
}

body {
    margin-bottom: 60px;
    background-color: #e6f2ff;
}

.fondo-principal {
    background: url('/imagenes/fondo.jpeg') no-repeat center center fixed;
    background-size: cover;
    min-height: 100vh; /* ocupa toda la pantalla */
    display: flex;
    align-items: center;
    justify-content: center;
    color: white; /* texto blanco encima del fondo */
    text-shadow: 2px 2px 5px rgba(0,0,0,0.7); /* mejora la legibilidad */
}