Navbar color schemes in Bootsrap - Practice Problems & Coding Challenges

Challenge - 5 Problems

❓ rendering

intermediate

What color scheme does this Bootstrap navbar use?

Look at the navbar code below. What color scheme will the navbar have when rendered in a browser?

Bootsrap

<nav class="navbar navbar-expand-lg navbar-dark bg-primary">
  <a class="navbar-brand" href="#">Brand</a>
</nav>

A Light background with light text

B Light background with dark text

C Dark background with light text

D Transparent background with dark text

💡 Hint

The class 'navbar-dark' changes text color to light, and 'bg-primary' sets a dark blue background.

The 'navbar-dark' class makes the text light colored, suitable for dark backgrounds. The 'bg-primary' class applies a dark blue background. Together, they create a dark background with light text color scheme.

📝 Syntax

intermediate

Which option will cause a syntax error in this Bootstrap navbar?

Identify which navbar code snippet will cause a syntax error and fail to render correctly.

A

<nav class="navbar navbar-light bg-light">
  <a class="navbar-brand" href="#">Brand</a>
</nav>

B

<nav class="navbar navbar-dark bg-dark">
  <a class="navbar-brand" href="#">Brand</a>
</nav>

C

>van/<
>a/<dnarB>"#"=ferh "dnarb-rabvan"=ssalc a<  
>"thgil-gb thgil-rabvan rabvan"=ssalc van<

D

<nav class="navbar navbar-dark bg-primary">
  <a class="navbar-brand" href="#">Brand</a>
</nav>

💡 Hint

Check if all tags are properly closed.

Option A is missing the closing '>' for the closing nav tag, causing a syntax error in HTML and preventing correct rendering.

❓ selector

advanced

Which CSS selector targets the navbar brand text in Bootstrap?

Given a Bootstrap navbar, which CSS selector correctly selects the brand text link for styling?

Bootsrap

<nav class="navbar navbar-expand-lg navbar-light bg-light">
  <a class="navbar-brand" href="#">Brand</a>
</nav>

A .navbar-brand a

B .navbar .navbar-brand

C nav > .brand

D .navbar-brand > nav

💡 Hint

The brand text has class 'navbar-brand' inside an element with class 'navbar'.

Option B selects any element with class 'navbar-brand' inside an element with class 'navbar', which matches the brand link. Other options are invalid selectors or select wrong elements.

❓ layout

advanced

How does the 'navbar-expand-lg' class affect the navbar layout?

What is the effect of adding 'navbar-expand-lg' to a Bootstrap navbar?

Bootsrap

<nav class="navbar navbar-expand-lg navbar-light bg-light">
  <a class="navbar-brand" href="#">Brand</a>
  <button class="navbar-toggler" type="button" data-toggle="collapse" data-target="#navbarNav">
    <span class="navbar-toggler-icon"></span>
  </button>
  <div class="collapse navbar-collapse" id="navbarNav">
    <ul class="navbar-nav">
      <li class="nav-item active">
        <a class="nav-link" href="#">Home</a>
      </li>
    </ul>
  </div>
</nav>

A Navbar expands only on extra small screens

B Navbar is always expanded horizontally on all screen sizes

C Navbar is always collapsed on all screen sizes

D Navbar expands horizontally on large screens and collapses on smaller screens

💡 Hint

'navbar-expand-lg' controls when the navbar changes from collapsed to expanded based on screen width.

The 'navbar-expand-lg' class makes the navbar show its full horizontal menu on large screens (lg and up) and collapse into a toggle menu on smaller screens.

❓ accessibility

expert

Which attribute improves accessibility for the navbar toggle button?

In a Bootstrap navbar, which attribute on the toggle button best helps screen reader users understand its purpose?

Bootsrap

<button class="navbar-toggler" type="button" data-toggle="collapse" data-target="#navbarNav">
  <span class="navbar-toggler-icon"></span>
</button>

A aria-label="Toggle navigation"

B alt="Toggle menu icon"

C tabindex="-1"

D role="button"

💡 Hint

Screen readers need a clear label describing the button's function.

The 'aria-label' attribute provides a descriptive text for screen readers, explaining the button toggles navigation. 'role="button"' is redundant on a button element, 'tabindex="-1"' removes keyboard focus, and 'alt' is for images, not buttons.

Practice

1. Which Bootstrap class should you use to make the navbar text dark and suitable for a light background?

easy

A. navbar-dark

B. navbar-light

C. bg-dark

D. text-light

Solution

1. Step 1: Understand navbar text color classes

   The navbar-light class makes text dark for readability on light backgrounds.

2. Step 2: Match class to background type

   Since the background is light, navbar-light is appropriate, unlike navbar-dark which is for dark backgrounds.

3. Final Answer:

   navbar-light -> Option B

4. Quick Check:

   Light background needs dark text = navbar-light [OK]

Hint: Light background? Use navbar-light for dark text [OK]

Common Mistakes:

• Confusing navbar-light with navbar-dark
• Using bg-dark instead of navbar color scheme
• Applying text-light on light backgrounds

2. Which of the following is the correct way to apply a dark navbar with a dark background in Bootstrap?

easy

A. <nav class='navbar navbar-light bg-dark'>

B. <nav class='navbar navbar-dark bg-light'>

C. <nav class='navbar navbar-light bg-light'>

D. <nav class='navbar navbar-dark bg-dark'>

Solution

1. Step 1: Identify the correct navbar text color for dark background

   For dark backgrounds, navbar-dark ensures text is light and readable.

2. Step 2: Match background color class

   The background class bg-dark sets a dark background color.

3. Final Answer:

   <nav class='navbar navbar-dark bg-dark'> -> Option D

4. Quick Check:

   Dark background needs navbar-dark + bg-dark [OK]

Hint: Dark background? Use navbar-dark with bg-dark [OK]

Common Mistakes:

• Mixing navbar-light with bg-dark
• Using bg-light with navbar-dark
• Forgetting to include both navbar and bg classes

3. What will be the visible text color of the navbar brand in this code?

<nav class='navbar navbar-dark bg-primary'>
  <a class='navbar-brand' href='#'>Brand</a>
</nav>

medium

A. Dark text color

B. Primary blue text color

C. Light text color

D. Default black text color

Solution

1. Step 1: Understand navbar-dark effect on text

   The navbar-dark class makes text light-colored for contrast on dark backgrounds.

2. Step 2: Recognize bg-primary background

   bg-primary is a dark blue background, so light text is used for readability.

3. Final Answer:

   Light text color -> Option C

4. Quick Check:

   navbar-dark + dark bg = light text [OK]

Hint: navbar-dark means light text on dark backgrounds [OK]

Common Mistakes:

• Assuming text matches bg-primary color
• Thinking navbar-dark means dark text
• Ignoring the effect of navbar-dark on text color

4. Identify the error in this navbar code snippet:

<nav class='navbar navbar-light bg-dark'>
  <a class='navbar-brand' href='#'>Brand</a>
</nav>

medium

A. Using navbar-light with a dark background

B. Missing navbar-expand class

C. Incorrect use of navbar-brand class

D. Missing href attribute in anchor tag

Solution

1. Step 1: Check navbar color scheme consistency

   The class navbar-light is for light backgrounds, but bg-dark sets a dark background.

2. Step 2: Understand readability issue

   This mismatch causes dark background with dark text, reducing readability.

3. Final Answer:

   Using navbar-light with a dark background -> Option A

4. Quick Check:

   navbar-light must pair with light backgrounds [OK]

Hint: Match navbar-light with light bg, navbar-dark with dark bg [OK]

Common Mistakes:

• Ignoring navbar-expand necessity
• Thinking navbar-brand needs href fix
• Confusing navbar-light and navbar-dark usage

5. You want a navbar with a light background but dark text and a custom green background color using Bootstrap utilities. Which class combination is correct?

hard

A. navbar navbar-light bg-success

B. navbar navbar-dark bg-light

C. navbar navbar-light bg-light

D. navbar navbar-dark bg-success

Solution

1. Step 1: Identify background color and text color needs

   You want a light background with dark text. The green background bg-success is a bright green, considered light.

2. Step 2: Choose matching navbar text color class

   For light backgrounds, navbar-light is used to make text dark and readable.

3. Final Answer:

   navbar navbar-light bg-success -> Option A

4. Quick Check:

   Light bg (green) needs navbar-light for dark text [OK]

Hint: Light or bright bg? Use navbar-light for dark text [OK]

Common Mistakes:

• Using navbar-dark with bright green background
• Choosing bg-light instead of desired green
• Mixing navbar-dark with light backgrounds