body {
  background-color: #f5f8fc;
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
}

header {
  background: linear-gradient(to right, #0052cc, #0088ff);
  box-shadow: 0 4px 8px rgba(0,0,0,0.2);
}

h1, h2, h3 {
  font-weight: 600;
}

form {
  background-color: white;
  padding: 1.5rem;
  border-radius: 15px;
  box-shadow: 0 3px 12px rgba(0,0,0,0.1);
}

.form-label {
  font-size: 1.1rem;
}

.form-control, .form-select {
  padding: 1rem;
  font-size: 1.2rem;
  border-radius: 10px;
}

#go {
  padding: 0.8rem 2rem;
  font-size: 1.2rem;
  border-radius: 10px;
  background-color: #0066ff;
  border: none;
  transition: background 0.3s;
}

#go:hover {
  background-color: #004ec2;
}

#result {
  animation: fadeIn 0.5s ease-in-out;
  background: #ffffff;
  padding: 1rem;
  border-radius: 10px;
  margin-top: 1rem;
  box-shadow: 0 2px 6px rgba(0,0,0,0.05);
}

.resultado-grande {
  font-size: 2em;
  font-weight: bold;
  color: #2c3e50;
  margin-top: 1em;
  text-align: center;
}

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

@media (max-width: 768px) {
  h1, h2 {
    font-size: 1.5rem;
  }

  form {
    padding: 1rem;
  }

  .form-label, .form-control, .form-select {
    font-size: 1rem;
  }

  #go {
    width: 100%;
    font-size: 1rem;
  }
}