body {
  font-family: Arial, sans-serif;
  background-color: #f4f4f4;
  color: #222;
  margin: 0;
  padding: 0;
}

header {
  background-color: #2d6cdf;
  color: white;
  text-align: center;
  padding: 40px 20px;
}

.karte {
  background-color: white;
  max-width: 700px;
  margin: 30px auto;
  padding: 20px;
  border-radius: 12px;
}

button {
  background-color: #2d6cdf;
  color: white;
  border: none;
  padding: 10px 16px;
  border-radius: 8px;
}