body {
  margin: 0;
  font-family: Arial, sans-serif;
  background: #f5f5f5;
  text-align: center;
}

header {
  background: #333;
  color: #fff;
  padding: 20px;
}

.card {
  background: #fff;
  margin: 40px auto;
  padding: 20px;
  width: 300px;
  border-radius: 10px;
  box-shadow: 0 4px 10px rgba(0,0,0,0.1);
}

button {
  padding: 10px 20px;
  border: none;
  background: #007bff;
  color: #fff;
  border-radius: 5px;
  cursor: pointer;
}

button:hover {
  background: #0056b3;
}

footer {
  margin-top: 40px;
  padding: 10px;
  background: #eee;
}