.container {
  max-width: 500px;
  margin: 0 auto;
  text-align: center;
}

h1 {
  font-size: 2.5rem;
  margin-bottom: 30px;
}

form {
  display: flex;
  flex-direction: column;
  align-items: center;
  margin-bottom: 30px;
}

.form-group {
  margin-bottom: 20px;
}

label {
  font-size: 1.2rem;
  display: block;
  margin-bottom: 10px;
}

input[type="number"] {
  border: none;
  padding: 10px;
  border-radius: 5px;
  box-shadow: 0 0 5px rgba(0, 0, 0, 0.2);
  font-size: 1.2rem;
  width: 100%;
  max-width: 300px;
}

button {
  border: none;
  padding: 10px 20px;
  background-color: #4CAF50;
  color: #fff;
  border-radius: 5px;
  cursor: pointer;
  font-size: 1.2rem;
  transition: background-color 0.3s;
}

button:hover {
  background-color: #3e8e41;
}

#result {
  font-size: 1.5rem;
  font-weight: bold;
}