/* default (desktop ≥1024 px) already 100 px */
section { margin-bottom: 100px; }

/* Tablet: 768 – 1023 px → 80 px gap */
@media (max-width: 1023px) {
  section { margin-bottom: 60px; }
}

/* Mobile: ≤ 767 px → 60 px gap */
@media (max-width: 767px) {
  section { margin-bottom: 60px; }
}