Mobile-First Responsive Design Patterns

Mobile-first means content priority and touch ergonomics drive the default stylesheet—not squeezing desktop layouts at 375px.

Breakpoint strategy

Start with single column, add complexity:

.card-grid {
  display: grid;
  grid-template-columns: 1fr;
}
@media (min-width: 768px) {
  .card-grid { grid-template-columns: repeat(2, 1fr); }
}

Touch targets

Minimum 44×44px interactive areas with adequate spacing—fat-finger errors cost conversions on checkout.

Content priority

Mobile shows: headline, primary CTA, one proof point. Secondary links move to footer or progressive disclosure—not hidden hamburger-only surprises.

Performance on mobile networks

• Hero image responsive srcset
• Defer non-critical JS
• Test on 3G throttling in DevTools

Navigation patterns

Bottom nav for 3–5 primary destinations on apps; hamburger acceptable for long-tail settings only.

Mobile-first is constraint-driven design—decisions get easier when small screen is the default canvas.