Part 35: Mobile-First Responsive Design Philosophy
Tailwind CSS employs a strict Mobile-First responsive architecture using min-width media queries.
1. How Mobile-First Works
Unprefixed utilities apply to all screen sizes (starting from mobile). Breakpoint prefixes apply to that screen size and larger:
<!-- On mobile: font size is small (text-sm)
On medium screens (md: 768px+): font size increases to base
On large screens (lg: 1024px+): font size becomes xl -->
<h2 class="text-sm md:text-base lg:text-xl">Responsive Headline</h2>
⚠️ Common Beginner Anti-Pattern:
Don't write sm:text-sm md:text-base if text-sm is your default. Simply write:
<h2 class="text-sm md:text-base">Headline</h2>
Key Takeaways
- Design for mobile first, then layer on larger screen adjustments with prefixes.
- Unprefixed classes define the mobile foundation.
In Part 36, we explore the Standard Breakpoints: sm, md, lg, xl, and 2xl!

