* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body {
  font-family: Arial, sans-serif;
  background-color: #0f172a;
  color: #ffffff;
  text-align: center;
  padding: 40px;
}

header {
  margin-bottom: 20px;
}

button {
  margin-top: 20px;
  padding: 10px 20px;
  border: none;
  background-color: #3b82f6;
  color: white;
  cursor: pointer;
  border-radius: 5px;
}

button:hover {
  background-color: #2563eb;
}