Button sizes in Bootsrap - Practice Problems & Coding Challenges

Challenge - 5 Problems

❓ rendering

intermediate

What size will this Bootstrap button render?

Given the following button code, what size will the button appear in the browser?

Bootsrap

<button type="button" class="btn btn-primary btn-lg">Click me</button>

A A medium (default) sized button

B A very small button

C A large button

D A button with extra padding but default font size

💡 Hint

Look at the class that controls size: btn-lg means large.

The class btn-lg in Bootstrap makes the button large. Without it, buttons are medium sized by default.

🧠 Conceptual

intermediate

Which class sets a small Bootstrap button?

Which Bootstrap class should you add to a button to make it smaller than the default size?

A btn-sm

B btn-xs

C btn-small

D btn-mini

💡 Hint

Bootstrap uses btn-sm for small buttons, not btn-xs or others.

The correct class for a small button in Bootstrap is btn-sm. Other classes like btn-xs or btn-mini are not valid in Bootstrap 5.

📝 Syntax

advanced

What error occurs with this button size class?

What happens if you use this button code in Bootstrap 5?

<button class="btn btn-primary btn-xs">Click</button>

Bootsrap

<button class="btn btn-primary btn-xs">Click</button>

A Button is hidden

B The button renders with default size because btn-xs is not recognized

C Button renders extra large

D Syntax error in HTML

💡 Hint

Bootstrap 5 does not have btn-xs class.

The class btn-xs is not defined in Bootstrap 5. The button will ignore it and render with default size.

❓ selector

advanced

Which CSS selector targets all large Bootstrap buttons?

Which CSS selector will select all buttons with the large size class in Bootstrap?

A .btn .btn-lg

B .btn-lg button

C button .btn-lg

D button.btn-lg

💡 Hint

Look for buttons that have both btn and btn-lg classes.

The selector button.btn-lg selects all <button> elements with the class btn-lg. Other options select descendants or are invalid.

❓ accessibility

expert

How to make a large Bootstrap button accessible?

You have a large button with class btn-lg. What should you add to improve accessibility for screen readers?

Bootsrap

<button class="btn btn-primary btn-lg">Submit</button>

A Add aria-label="Submit form" to describe the button action

B Add tabindex="-1" to prevent keyboard focus

C Add role="presentation" to hide it from screen readers

D Add style="font-size: 2rem;" inline for better visibility

💡 Hint

Screen readers need clear descriptions of button actions.

Adding aria-label gives screen readers a clear description of what the button does. tabindex="-1" removes keyboard focus which harms accessibility. role="presentation" hides the button from assistive tech, which is wrong. Inline styles do not improve accessibility.

Practice

1. Which Bootstrap class makes a button smaller than the default size?
<button class="btn btn-primary ?">Click</button>

easy

A. btn-sm

B. btn-lg

C. btn-default

D. btn-small

Solution

1. Step 1: Understand Bootstrap button size classes

   Bootstrap uses btn-sm for small buttons and btn-lg for large buttons. The default button has no size class.

2. Step 2: Identify the class for smaller buttons

   The class btn-sm is the correct one to make a button smaller than default.

3. Final Answer:

   btn-sm -> Option A

4. Quick Check:

   Small button class = btn-sm [OK]

Hint: Small buttons use btn-sm class in Bootstrap [OK]

Common Mistakes:

• Using btn-lg for small buttons
• Using btn-default which is not a size class
• Using btn-small which does not exist

2. Which of the following is the correct syntax to create a large Bootstrap button?
<button class="btn btn-primary ?">Submit</button>

easy

A. btn-lg

B. btn-large

C. btn-big

D. btn-xl

Solution

1. Step 1: Recall Bootstrap large button class

   Bootstrap uses btn-lg to make buttons larger than the default size.

2. Step 2: Match the correct class syntax

   The correct class is btn-lg. Other options like btn-large, btn-big, or btn-xl are not valid Bootstrap classes.

3. Final Answer:

   btn-lg -> Option A

4. Quick Check:

   Large button class = btn-lg [OK]

Hint: Large buttons use btn-lg class in Bootstrap [OK]

Common Mistakes:

• Using btn-large instead of btn-lg
• Using btn-big which is not a Bootstrap class
• Using btn-xl which does not exist in Bootstrap

3. What will be the visual difference between these two buttons?

<button class="btn btn-primary">Default</button>
<button class="btn btn-primary btn-sm">Small</button>

medium

A. Both buttons will be the same size

B. The first button is smaller, the second is default size

C. The first button is larger, the second is default size

D. The first button is default size, the second is smaller

Solution

1. Step 1: Identify button classes and their sizes

   The first button has only btn btn-primary, so it is default size. The second button adds btn-sm, making it smaller.

2. Step 2: Understand visual difference

   The second button will appear smaller than the first because of the btn-sm class.

3. Final Answer:

   The first button is default size, the second is smaller -> Option D

4. Quick Check:

   btn-sm makes button smaller [OK]

Hint: btn-sm makes button smaller than default [OK]

Common Mistakes:

• Thinking btn-sm makes button larger
• Assuming both buttons look the same
• Confusing btn-sm with btn-lg

4. Identify the error in this Bootstrap button code:

<button class="btn btn-primary btn-small">Click Me</button>

medium

A. Missing closing tag for button

B. btn-primary cannot be combined with size classes

C. btn-small is not a valid Bootstrap size class

D. btn class is missing

Solution

1. Step 1: Check Bootstrap size classes

   Bootstrap uses btn-sm and btn-lg for sizes. btn-small is not valid.

2. Step 2: Verify other classes and syntax

   The btn-primary and btn classes are correct and present. The button tag is properly closed.

3. Final Answer:

   btn-small is not a valid Bootstrap size class -> Option C

4. Quick Check:

   Use btn-sm or btn-lg for sizes [OK]

Hint: Use btn-sm or btn-lg, not btn-small [OK]

Common Mistakes:

• Using btn-small instead of btn-sm
• Thinking btn-primary can't combine with size classes
• Missing btn class in button

5. You want a form with two buttons: a large green 'Save' button and a small red 'Cancel' button. Which code snippet correctly applies Bootstrap button sizes and colors?

hard

A. <button class="btn btn-success btn-sm">Save</button> <button class="btn btn-danger btn-lg">Cancel</button>

B. <button class="btn btn-success btn-lg">Save</button> <button class="btn btn-danger btn-sm">Cancel</button>

C. <button class="btn btn-primary btn-lg">Save</button> <button class="btn btn-warning btn-sm">Cancel</button>

D. <button class="btn btn-danger btn-lg">Save</button> <button class="btn btn-success btn-sm">Cancel</button>

Solution

1. Step 1: Match button colors to meanings

   Bootstrap uses btn-success for green and btn-danger for red buttons.

2. Step 2: Apply correct sizes to buttons

   The 'Save' button should be large, so use btn-lg. The 'Cancel' button should be small, so use btn-sm.

3. Step 3: Verify the correct combination

   <button class="btn btn-success btn-lg">Save</button> <button class="btn btn-danger btn-sm">Cancel</button> correctly uses btn-success btn-lg for 'Save' and btn-danger btn-sm for 'Cancel'. Other options swap colors or sizes incorrectly.

4. Final Answer:

   <button class="btn btn-success btn-lg">Save</button> <button class="btn btn-danger btn-sm">Cancel</button> -> Option B

5. Quick Check:

   Green = btn-success, Large = btn-lg, Red = btn-danger, Small = btn-sm [OK]

Hint: Green = btn-success, Red = btn-danger, sizes btn-lg/sm [OK]

Common Mistakes:

• Swapping btn-success and btn-danger classes
• Using wrong size classes for buttons
• Mixing colors and sizes incorrectly