body {
  font-family: Arial, sans-serif;
  margin: 0;
  padding: 0;
  background: #f4f4f4;
  color: #333;
}
header {
  background-color: #0a0a0a;
  color: white;
  padding: 20px;
  text-align: center;
}
nav {
  background: #222;
  padding: 10px 0;
  text-align: center;
}
nav a {
  color: white;
  margin: 0 15px;
  text-decoration: none;
  font-weight: bold;
}
.container {
  max-width: 900px;
  margin: 40px auto;
  padding: 20px;
  background: white;
  box-shadow: 0 0 8px rgba(0,0,0,0.1);
  border-radius: 8px;
}
footer {
  background: #0a0a0a;
  color: white;
  text-align: center;
  padding: 15px 0;
  margin-top: 40px;
}