body {
  font-family: sans-serif;
  background-color: #f4f4f9;
  display: flex;
  justify-content: center;
  padding: 20px;
}
.container {
  background: white;
  padding: 2rem;
  border-radius: 8px;
  box-shadow: 0 4px 8px rgba(0, 0, 0, 0.1);
  max-width: 600px;
  width: 100%;
}
h1 {
  color: #333;
  text-align: center;
}
.card {
  margin-top: 20px;
  padding: 20px;
  border: 1px solid #eee;
  border-radius: 5px;
}
button {
  background-color: #007bff;
  color: white;
  border: none;
  padding: 10px 20px;
  border-radius: 5px;
  cursor: pointer;
}
button:hover {
  background-color: #0056b3;
}
.result-box {
  margin-top: 15px;
  padding: 15px;
  background: #e9ecef;
  border-radius: 5px;
}
.hidden {
  display: none;
}
.success {
  color: green;
}
.error {
  color: red;
}