body {
  font-family: Arial, sans-serif;
  text-align: center;
  background-color: #f4f4f4;
  transition: background-color 0.5s ease-in-out;
  padding: 20px;
}
.container {
  background: white;
  padding: 20px;
  border-radius: 10px;
  box-shadow: 0 0 10px rgba(0, 0, 0, 0.1);
  max-width: 400px;
  margin: auto;
}
input {
  width: 80%;
  padding: 10px;
  margin: 10px 0;
  border: 1px solid #ddd;
  border-radius: 5px;
  text-align: center;
}
button {
  background-color: #007bff;
  color: white;
  border: none;
  padding: 10px;
  width: 100%;
  border-radius: 5px;
  cursor: pointer;
  font-size: 16px;
}
button:hover {
  background-color: #0056b3;
}
.result {
  margin-top: 20px;
  font-size: 18px;
  font-weight: bold;
  padding: 10px;
  border-radius: 5px;
  opacity: 0;
  transform: translateY(10px);
  transition: opacity 0.5s ease-out, transform 0.5s ease-out;
}
.result.show {
  opacity: 1;
  transform: translateY(0);
}
.error {
  color: red;
}