body {
  font-family: "Segoe UI", Arial, sans-serif;
  background-color: #f4f6fa;
  margin: 0;
  padding: 0;
}
header {
  background-color: #061b2e;
  color: white;
  text-align: center;
  padding: 1rem;
}
nav a {
  color: #0cf;
  text-decoration: none;
  margin: 0 10px;
}
main {
  padding: 20px;
}
.card {
  background: #fff;
  border-radius: 10px;
  padding: 15px;
  box-shadow: 0 2px 4px rgba(0,0,0,0.1);
  margin-bottom: 20px;
}
footer {
  text-align: center;
  padding: 15px;
  color: #444;
}