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

.container {
  max-width: 500px;
  margin: auto;
  padding: 20px;
  background: white;
}

button {
  width: 100%;
  padding: 15px;
  font-size: 18px;
  background: #ff4d4d;
  color: white;
  border: none;
}