/* Reset & base styles */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  font-family: "Segoe UI", sans-serif;
}

body {
  background-color: #f4f4f4;
  color: #333;
  line-height: 1.6;
  padding: 20px;
}

/* Header and navigation */
header {
  background: #004466;
  color: white;
  padding: 20px 0;
  text-align: center;
  border-bottom: 5px solid #00aaff;
}

nav {
  background: #006699;
  text-align: center;
  padding: 10px 0;
}

nav a {
  color: white;
  text-decoration: none;
  margin: 0 15px;
  font-weight: bold;
}

nav a:hover {
  text-decoration: underline;
}

/* Main content */
main, .container {
  max-width: 960px;
  margin: auto;
  background: white;
  padding: 20px;
  border-radius: 8px;
  box-shadow: 0 0 10px rgba(0,0,0,0.1);
}

/* Footer */
footer {
  background: #004466;
  color: white;
  text-align: center;
  padding: 15px 0;
  margin-top: 40px;
}

/* Responsive layout */
@media (max-width: 768px) {
  nav a {
    display: block;
    margin: 10px 0;
  }

  body {
    padding: 10px;
  }
}