* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: Arial, Helvetica, sans-serif;
  background: #f4f7fb;
  color: #1f2937;
}

header {
  padding: 48px 20px;
  text-align: center;
  background: #1f4e79;
  color: white;
}

nav {
  display: flex;
  justify-content: center;
  gap: 24px;
  padding: 16px;
  background: #163a5c;
}

nav a {
  color: white;
  text-decoration: none;
  font-weight: bold;
}

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

main {
  width: min(900px, 92%);
  margin: 32px auto;
}

.card {
  background: white;
  margin-bottom: 24px;
  padding: 24px;
  border-radius: 12px;
  box-shadow: 0 4px 14px rgba(0, 0, 0, 0.08);
}

button {
  padding: 10px 18px;
  border: none;
  border-radius: 8px;
  background: #1f4e79;
  color: white;
  cursor: pointer;
}

button:hover {
  opacity: 0.9;
}

footer {
  text-align: center;
  padding: 24px;
  margin-top: 40px;
  background: #163a5c;
  color: white;
}