@media (max-width: 768px) {
  .hamburger { display: block; }
  .nav-links {
    position: absolute;
    top: 100%; left: 0; width: 100%;
    background: var(--dark);
    flex-direction: column;
    padding: 20px;
    display: none;
    border-bottom: 2px solid var(--primary);
  }
  .nav-links.active { display: flex; }
  .hero h1 { font-size: 2.8rem; }
  .slogan { font-size: 1.3rem; }
}