body {
  font-family: Arial;
  background: #f5f5f5;
  margin: 0;
}

.container {
  width: 500px;
  margin: 100px auto;
  background: white;
  padding: 40px;
  border-radius: 12px;
  box-shadow: 0 0 10px rgba(0,0,0,0.1);
}

button {
  background: #2563eb;
  color: white;
  border: none;
  padding: 12px 20px;
  border-radius: 8px;
  cursor: pointer;
}