Mobile-first philosophy in Tailwind - Mini Project: Build & Apply

Mobile-First Responsive Card with Tailwind CSS

📖 Scenario: You are building a simple profile card for a mobile app. The card should look good on small screens first, then adjust for larger screens.

🎯 Goal: Create a responsive profile card using Tailwind CSS that is mobile-friendly by default and changes layout on larger screens.

📋 What You'll Learn

Use Tailwind CSS utility classes

Start with a vertical layout for mobile screens

Change to a horizontal layout on screens medium and larger

Include an image, a name, and a short description

Use semantic HTML elements

💡 Why This Matters

🌍 Real World

Profile cards are common in social apps, team pages, and portfolios. Mobile-first design ensures good experience on phones.

💼 Career

Understanding mobile-first responsive design with Tailwind CSS is essential for front-end developers building modern websites and apps.

1

Create the basic HTML structure for the profile card

Write the HTML code to create a <section> element with a class max-w-sm mx-auto p-4. Inside it, add an <img> with src='https://via.placeholder.com/150' and alt='Profile picture'. Below the image, add a <h2> with the text Jane Doe and a <p> with the text Web developer and designer.

Tailwind

Hint

Use a section with classes for max width, center alignment, and padding. Add an img, h2, and p inside.

2

Add Tailwind classes for mobile-first styling

Add Tailwind CSS classes to the img to make it rounded with rounded-full, centered with mx-auto, and width w-24. Add classes text-center mt-4 to the h2 and p elements to center the text and add margin top.

Tailwind

  
  Jane Doe
  Web developer and designer
  

Hint

Use rounded-full for circle image, mx-auto to center horizontally, and w-24 for width. Center text with text-center and add margin top with mt-4.

3

Add responsive layout for medium screens and larger

Modify the section to use md:flex md:items-center md:space-x-6 classes. Add md:w-32 to the img to make it smaller on medium screens. Add md:text-left to the h2 and p to align text left on medium screens.

Tailwind

  
  
    Jane Doe
    Web developer and designer
  
  

Hint

Use md:flex to switch to horizontal layout on medium screens. Use md:items-center to align vertically. Add spacing with md:space-x-6. Adjust image width with md:w-32. Change text alignment with md:text-left.

4

Add accessibility and final touches

Wrap the h2 and p inside a <div> for grouping. Add aria-label="Profile card for Jane Doe" to the section for accessibility. Ensure the image has an alt attribute describing it.

Tailwind

  
  
    Jane Doe
    Web developer and designer
  
  

Hint

Add aria-label to the section for screen readers. Make sure the image has a descriptive alt attribute.

Practice

1. What does the mobile-first philosophy mean in web design?

easy

A. Designing for small screens first, then adding styles for larger screens

B. Designing only for desktop screens

C. Designing for large screens first, then adjusting for smaller screens

D. Ignoring screen sizes and using fixed layouts

Solution

1. Step 1: Understand mobile-first philosophy

   Mobile-first means starting design with small screens like phones, then adding styles for bigger screens.

2. Step 2: Compare options

   Only Designing for small screens first, then adding styles for larger screens correctly describes this approach; others describe desktop-first or fixed layouts.

3. Final Answer:

   Designing for small screens first, then adding styles for larger screens -> Option A

4. Quick Check:

   Mobile-first = Start small screens first [OK]

Hint: Mobile-first means start small, then grow bigger [OK]

Common Mistakes:

• Thinking mobile-first means designing desktop first
• Confusing mobile-first with ignoring screen sizes
• Believing mobile-first means only designing for phones

2. Which Tailwind CSS class applies styles only on medium and larger screens?

easy

A. md:bg-blue-500

B. bg-blue-500

C. sm:bg-blue-500

D. lg:bg-blue-500

Solution

1. Step 1: Understand Tailwind screen prefixes

   In Tailwind, md: applies styles at medium screen size and above.

2. Step 2: Identify correct prefix for medium screens

   md:bg-blue-500 uses md:, so it applies on medium and larger screens. Others apply on small, large, or all screens.

3. Final Answer:

   md:bg-blue-500 -> Option A

4. Quick Check:

   md: means medium screens and up [OK]

Hint: Remember md: prefix targets medium+ screens [OK]

Common Mistakes:

• Confusing sm: with md:
• Using no prefix and expecting medium-only styles
• Mixing lg: with md:

3. Given this Tailwind code:

<div class="bg-red-500 md:bg-green-500">Box</div>

What background color will the box have on a small screen?

medium

A. Green

B. Red

C. No color

D. Blue

Solution

1. Step 1: Analyze classes on small screen

   The class bg-red-500 applies to all screens by default. The md:bg-green-500 applies only on medium and larger screens.

2. Step 2: Determine active class on small screen

   On small screens, md:bg-green-500 is ignored, so background stays red.

3. Final Answer:

   Red -> Option B

4. Quick Check:

   Default class applies on small screens [OK]

Hint: Default classes apply on all screens unless overridden [OK]

Common Mistakes:

• Thinking md: classes apply on small screens
• Ignoring default classes
• Assuming no color if md: class exists

4. What is wrong with this Tailwind code if the goal is to make text blue on small screens and red on medium and larger screens?

<p class="md:text-red-500 text-blue-500">Hello</p>

medium

A. The order of classes is reversed; it should be text-blue-500 md:text-red-500

B. The md: prefix should be on text-blue-500

C. No error; it works as intended

D. Tailwind does not support multiple text color classes

Solution

1. Step 1: Understand class application order

   Tailwind applies base classes first, then overrides with media prefixes like md:.

2. Step 2: Check if code matches goal

   text-blue-500 applies on all screens, overridden by md:text-red-500 on medium+ screens, matching the goal.

3. Final Answer:

   No error; it works as intended -> Option C

4. Quick Check:

   Base then md: override works [OK]

Hint: Base class first, then md: override for bigger screens [OK]

Common Mistakes:

• Thinking order of classes matters in Tailwind
• Believing md: prefix must be on base class
• Assuming Tailwind can't override colors

5. You want a button that is full width on small screens but only 200px wide on medium and larger screens using Tailwind. Which class combination achieves this?

hard

A. w-full w-[200px] md:w-full

B. md:w-full w-[200px]

C. w-[200px] md:w-full

D. w-full md:w-[200px]

Solution

1. Step 1: Understand mobile-first width classes

   Use w-full for full width on small screens (default). Use md:w-[200px] to set width 200px on medium+ screens.

2. Step 2: Check options for correct order and values

   w-full md:w-[200px] sets full width by default, then overrides to 200px on medium screens. Others reverse or duplicate incorrectly.

3. Final Answer:

   w-full md:w-[200px] -> Option D

4. Quick Check:

   Default full width, md override 200px [OK]

Hint: Default small screen first, then md: for bigger screens [OK]

Common Mistakes:

• Reversing order of width classes
• Using md: on full width instead of fixed width
• Duplicating conflicting width classes