/* Contenedor principal */
#contabilidad-app {
  max-width: 800px;
  margin: 2rem auto;
  padding: 2rem;
  background: #ffffff;
  border-radius: 8px;
  box-shadow: 0 4px 12px rgba(0,0,0,0.1);
  font-family: "Segoe UI", Roboto, sans-serif;
}

/* Título */
#contabilidad-app h2 {
  text-align: center;
  margin-bottom: 1.5rem;
  font-weight: 600;
  color: #2c3e50;
}

/* Formulario */
#transaccion-form label {
  display: block;
  margin-bottom: 0.25rem;
  font-weight: 500;
  color: #34495e;
}

#transaccion-form input,
#transaccion-form select {
  width: 100%;
  padding: 0.6rem;
  margin-bottom: 1rem;
  border: 1px solid #dcdcdc;
  border-radius: 6px;
  transition: border-color 0.2s ease;
}

#transaccion-form input:focus,
#transaccion-form select:focus {
  border-color: #3498db;
  outline: none;
}

/* Botón principal */
#transaccion-form button {
  width: 100%;
  padding: 0.8rem;
  background: #3498db;
  color: #fff;
  border: none;
  border-radius: 6px;
  font-weight: 600;
  cursor: pointer;
  transition: background 0.3s ease;
}

#transaccion-form button:hover {
  background: #2980b9;
}

/* Mensajes */
#resultado .alert,
#balance .alert {
  margin-top: 1rem;
  border-radius: 6px;
  font-size: 0.95rem;
}

/* Tabla responsiva */
#tabla-transacciones {
  width: 100%;
  border-collapse: collapse;
  margin-top: 1.5rem;
  font-size: 0.9rem;
}

#tabla-transacciones th,
#tabla-transacciones td {
  padding: 0.75rem;
  text-align: left;
  border-bottom: 1px solid #eaeaea;
}

#tabla-transacciones th {
  background: #f4f6f8;
  font-weight: 600;
  color: #2c3e50;
}

#tabla-transacciones tr:hover {
  background: #f9fbfd;
}

/* Scroll horizontal en móvil */
@media (max-width: 768px) {
  #tabla-transacciones {
    display: block;
    overflow-x: auto;
    white-space: nowrap;
  }
}