body {
  font-family: sans-serif;
  max-width: 800px;
  margin: auto;
  padding: 2rem;
  background: #f4f4f4;
}
.card {
  background: white;
  border-radius: 1rem;
  padding: 1rem;
  margin-bottom: 1rem;
  box-shadow: 0 2px 5px rgba(0,0,0,0.1);
}