Media queries in CSS - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is a media query in CSS?

A media query is a CSS technique that applies styles only when certain conditions about the device or screen are true, like screen width or orientation.

beginner

How do you write a basic media query for screens smaller than 600px?

Use @media (max-width: 600px) { /* CSS rules here */ } to apply styles only when the screen width is 600 pixels or less.

beginner

What does min-width mean in a media query?

min-width means the styles inside the media query apply only if the screen width is at least the specified value.

intermediate

Why are media queries important for accessibility?

They help make websites easier to use on different devices and screen sizes, improving readability and navigation for everyone.

intermediate

What is the difference between max-width and min-width in media queries?

max-width applies styles up to a certain screen width, while min-width applies styles from that width and above.

Which media query applies styles only on screens wider than 800px?

A @media screen and (max-width: 800px)

B @media (max-width: 800px)

C @media (min-width: 800px)

D @media (width: 800px)

The min-width condition applies styles when the screen width is at least 800px.

What does this media query do? @media (max-width: 500px) { ... }

A Applies styles only if screen width is more than 500px

B Applies styles on all devices

C Applies styles only on devices with exactly 500px width

D Applies styles only if screen width is 500px or less

The max-width condition targets screens up to 500px wide.

Which media feature is used to detect device orientation?

A orientation

B aspect-ratio

C resolution

D color

The orientation media feature detects if the device is in portrait or landscape mode.

How can you combine multiple conditions in a media query?

A Using <code>or</code> keyword

B Using <code>and</code> keyword

C Using <code>but</code> keyword

D Using <code>then</code> keyword

The and keyword combines multiple conditions that all must be true.

Which of these is a valid media query for print devices?

A @media print { ... }

B @media screen { ... }

C @media handheld { ... }

D @media all { ... }

The print media type targets printers and print previews.

Explain how media queries help make a website responsive.

Think about how websites look different on phones and computers.

Describe the difference between using min-width and max-width in media queries.

Consider small screens versus large screens.

Practice

1. What is the main purpose of CSS @media queries?

easy

A. To link external CSS files

B. To add animations to elements

C. To apply different styles based on device screen size or features

D. To create CSS variables

Solution

1. Step 1: Understand what @media does

   @media queries let CSS change styles depending on device features like screen width.

2. Step 2: Compare options to this purpose

   Only To apply different styles based on device screen size or features describes applying styles based on screen size or features, which matches @media usage.

3. Final Answer:

   To apply different styles based on device screen size or features -> Option C

4. Quick Check:

   Media queries = responsive styles [OK]

Hint: Media queries adapt styles to screen size or device [OK]

Common Mistakes:

• Confusing media queries with animations
• Thinking media queries link CSS files
• Mixing media queries with CSS variables

2. Which of the following is the correct syntax to apply styles only when the screen width is 600px or less?

easy

A. @media (width < 600px) { /* styles here */ }

B. @media (max-width: 600px) { /* styles here */ }

C. @media screen and (min-width: 600px) { /* styles here */ }

D. @media max-width: 600px { /* styles here */ }

Solution

1. Step 1: Recall correct media query syntax for max-width

   The correct syntax uses @media (max-width: 600px) with parentheses and colon.

2. Step 2: Check each option

   @media (max-width: 600px) { /* styles here */ } matches the correct syntax. @media screen and (min-width: 600px) { /* styles here */ } uses min-width, which is opposite. @media (width < 600px) { /* styles here */ } uses invalid syntax. @media max-width: 600px { /* styles here */ } misses parentheses.

3. Final Answer:

   @media (max-width: 600px) { /* styles here */ } -> Option B

4. Quick Check:

   Use parentheses and colon for max-width [OK]

Hint: Use parentheses and colon for conditions in @media [OK]

Common Mistakes:

• Omitting parentheses around conditions
• Using min-width instead of max-width for smaller screens
• Writing conditions without colon

3. Given this CSS, what background color will the body have on a screen 500px wide?

body { background-color: white; } @media (max-width: 600px) { body { background-color: lightblue; } }

medium

A. Lightblue

B. White

C. No background color

D. Black

Solution

1. Step 1: Understand media query condition

   The media query applies styles when screen width is 600px or less. 500px is less than 600px, so it applies.

2. Step 2: Determine which background color applies

   The media query sets background to lightblue, overriding the default white for this screen size.

3. Final Answer:

   Lightblue -> Option A

4. Quick Check:

   Screen 500px ≤ 600px uses media query color [OK]

Hint: Check if screen width meets media query condition [OK]

Common Mistakes:

• Ignoring media query and picking default style
• Confusing max-width with min-width
• Assuming no style applies if media query exists

4. Identify the error in this media query CSS:

@media max-width: 800px { p { font-size: 1.2rem; } }

medium

A. Using max-width instead of min-width

B. Missing semicolon after font-size

C. Incorrect selector inside media query

D. Missing parentheses around the condition

Solution

1. Step 1: Check media query syntax

   The condition must be inside parentheses: @media (max-width: 800px).

2. Step 2: Verify other parts

   The selector p is valid, and semicolon is present. Using max-width is correct if targeting screens 800px or less.

3. Final Answer:

   Missing parentheses around the condition -> Option D

4. Quick Check:

   Media query conditions need parentheses [OK]

Hint: Always wrap media conditions in parentheses [OK]

Common Mistakes:

• Forgetting parentheses around conditions
• Confusing max-width and min-width usage
• Missing semicolons inside CSS blocks

5. You want a paragraph's font size to be 1.5rem on screens wider than 900px, and 1rem on smaller screens. Which CSS correctly achieves this?

hard

A. p { font-size: 1.5rem; } @media (max-width: 900px) { p { font-size: 1rem; } }

B. @media (max-width: 900px) { p { font-size: 1.5rem; } } p { font-size: 1rem; }

C. @media (min-width: 900px) { p { font-size: 1rem; } } p { font-size: 1.5rem; }

D. p { font-size: 1rem; } @media (min-width: 900px) { p { font-size: 1.5rem; } }

Solution

1. Step 1: Understand the requirement

   Font size should be 1.5rem on screens wider than 900px, and 1rem on smaller screens.

2. Step 2: Analyze each option

   p { font-size: 1.5rem; } @media (max-width: 900px) { p { font-size: 1rem; } } sets default font size to 1.5rem, then uses a media query with max-width 900px to reduce font size to 1rem on smaller screens. This matches the requirement.

3. Final Answer:

   p { font-size: 1.5rem; } @media (max-width: 900px) { p { font-size: 1rem; } } -> Option A

4. Quick Check:

   Default large, smaller inside max-width media query [OK]

Hint: Set default for large, override smaller with max-width query [OK]

Common Mistakes:

• Reversing min-width and max-width logic
• Setting default smaller and overriding larger incorrectly
• Missing default style outside media query