body {
  margin: 0;
  font-family: 'Segoe UI', Arial, sans-serif;
  background: #f9f9f9;
  color: #222;
}
nav {
  background: #222;
  padding: 1rem 0.5rem;
  text-align: center;
}
nav a {
  color: #fff;
  text-decoration: none;
  margin: 0 1rem;
  font-weight: 500;
  transition: color 0.2s;
}
nav a:hover {
  color: #4fc3f7;
}
main {
  max-width: 700px;
  margin: 2rem auto 3rem auto;
  background: #fff;
  padding: 2rem 1.5rem;
  border-radius: 10px;
  box-shadow: 0 2px 12px rgba(0,0,0,0.06);
}
h1 {
  color: #1976d2;
  font-size: 2rem;
  margin-bottom: 1rem;
}
h2 {
  color: #333;
  font-size: 1.2rem;
  margin-top: 2rem;
}
footer {
  text-align: center;
  color: #888;
  font-size: 0.95rem;
  padding: 1.5rem 0 1rem 0;
  background: none;
}
ul {
  padding-left: 1.2rem;
}
@media (max-width: 600px) {
  main {
    padding: 1rem 0.5rem;
  }
  nav a {
    margin: 0 0.5rem;
    font-size: 0.98rem;
  }
}