Universal selector in CSS - Mini Project: Build & Apply

Styling All Elements with the Universal Selector

📖 Scenario: You are creating a simple webpage and want to apply a basic style to every element to ensure consistent spacing and font style.

🎯 Goal: Use the CSS universal selector * to apply a margin of 0 and a font family of Arial, sans-serif to all elements on the page.

📋 What You'll Learn

Create a CSS rule using the universal selector *

Set the margin property to 0 for all elements

Set the font-family property to Arial, sans-serif for all elements

💡 Why This Matters

🌍 Real World

Web designers often use the universal selector to reset or normalize styles across all elements to create a consistent base for their designs.

💼 Career

Understanding the universal selector helps in writing efficient CSS that applies broad styles quickly, a common task in front-end web development.

1

Create the CSS universal selector

Write a CSS rule using the universal selector * to select all elements.

CSS

/* Write a CSS rule using the universal selector * */
/* Your code here */

Hint

The universal selector is a single asterisk *. Start your CSS rule with * { and close it with }.

2

Add margin property to the universal selector

Inside the universal selector * rule, add a CSS property to set margin to 0.

CSS

* {
  /* Set margin to 0 for all elements */
  /* Your code here */
}

Hint

Use the syntax property: value; inside the curly braces.

3

Add font-family property to the universal selector

Add a CSS property inside the universal selector * rule to set font-family to Arial, sans-serif.

CSS

* {
  margin: 0;
  /* Set font-family to Arial, sans-serif for all elements */
  /* Your code here */
}

Hint

Remember to separate multiple properties with semicolons inside the CSS rule.

4

Complete the CSS rule for universal styling

Ensure the CSS rule using the universal selector * includes both margin: 0; and font-family: Arial, sans-serif; properties.

CSS

* {
  margin: 0;
  font-family: Arial, sans-serif;
  /* Final check: all properties included */
}

Hint

Make sure your CSS rule is complete and correctly formatted.

Practice

1. What does the CSS universal selector * do?

easy

A. Selects elements with a specific class

B. Selects only div elements

C. Selects all elements on the page

D. Selects elements with a specific ID

Solution

1. Step 1: Understand the universal selector symbol

   The * symbol in CSS means "all elements" without exception.

2. Step 2: Apply the selector meaning

   Using * targets every element on the page, regardless of tag, class, or ID.

3. Final Answer:

   Selects all elements on the page -> Option C

4. Quick Check:

   Universal selector = all elements [OK]

Hint: Remember * means every element on the page [OK]

Common Mistakes:

• Thinking * selects only specific tags
• Confusing * with class or ID selectors
• Assuming * targets only visible elements

2. Which of the following is the correct syntax to apply a margin of 0 to all elements using the universal selector?

easy

A. # * { margin: 0; }

B. . * { margin: 0; }

C. all { margin: 0; }

D. * { margin: 0; }

Solution

1. Step 1: Identify the universal selector syntax

   The universal selector is just * without any prefix like dot or hash.

2. Step 2: Check the CSS rule format

   The correct CSS rule to apply margin 0 to all elements is * { margin: 0; }.

3. Final Answer:

   * { margin: 0; } -> Option D

4. Quick Check:

   Universal selector syntax = * { ... } [OK]

Hint: Universal selector is just * without dot or hash [OK]

Common Mistakes:

• Adding dot or hash before *
• Using invalid selector names like 'all'
• Forgetting curly braces

3. Given this CSS code:

* { padding: 10px; }
p { padding: 5px; }

What will be the padding of a paragraph (<p>) element?

medium

A. 10px

B. 5px

C. 15px

D. 0px

Solution

1. Step 1: Understand selector specificity

   The universal selector * applies padding 10px to all elements, but the p selector is more specific.

2. Step 2: Apply CSS specificity rules

   Since p selector is more specific than *, the paragraph's padding will be 5px, overriding the universal selector.

3. Final Answer:

   5px -> Option B

4. Quick Check:

   More specific selector wins = 5px [OK]

Hint: More specific selector overrides * [OK]

Common Mistakes:

• Assuming * always overrides other selectors
• Adding padding values instead of overriding
• Ignoring CSS specificity rules

4. You wrote this CSS:

* { font-size: 16px }

But the browser ignores it and uses default font sizes. What is the likely error?

medium

A. CSS file not linked properly

B. Universal selector cannot set font size

C. Font size must be in quotes

D. Missing semicolon after 16px

Solution

1. Step 1: Check CSS syntax

   The CSS rule * { font-size: 16px } is syntactically valid; a trailing semicolon is optional at the end of a rule.

2. Step 2: Understand common issues

   If valid CSS is ignored by the browser, the stylesheet is likely not linked properly in the HTML with a <link rel="stylesheet" href="..."> tag.

3. Final Answer:

   CSS file not linked properly -> Option A

4. Quick Check:

   No styles applied? Check <link> tag [OK]

Hint: If * styles not applying, verify CSS file link [OK]

Common Mistakes:

• Thinking universal selector can't style fonts
• Using quotes around numeric values
• Ignoring CSS file linking issues

5. You want to reset margin and padding for all elements but keep links (<a>) with no margin and 5px padding. Which CSS achieves this?

hard

A. * { margin: 0; padding: 0; } a { padding: 5px; }

B. a { margin: 10px; padding: 5px; } * { margin: 0; padding: 0; }

C. * { margin: 0; padding: 5px; } a { margin: 0; padding: 0; }

D. * { margin: 0; padding: 0; a { padding: 5px; } }

Solution

1. Step 1: Reset all elements margin and padding

   The universal selector * { margin: 0; padding: 0; } sets margin and padding to zero for all elements.

2. Step 2: Override padding for links

   The selector a { padding: 5px; } specifically sets padding to 5px for all <a> elements, overriding the universal selector.

3. Final Answer:

   * { margin: 0; padding: 0; } a { padding: 5px; } -> Option A

4. Quick Check:

   Specific selector overrides universal [OK]

Hint: Use * first, then override with specific selector [OK]

Common Mistakes:

• Placing universal selector after specific selector
• Nesting selectors incorrectly
• Setting wrong padding values