Background size in CSS - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to make the background image cover the entire element.

CSS

background-size: [1];

Drag options to blanks, or click blank then click option'

Arepeat

Bcontain

Cauto

Dcover

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'contain' which fits the image inside but may leave empty space.

Using 'repeat' which repeats the image instead of resizing.

The cover value makes the background image cover the entire element, scaling it as needed.

2fill in blank

medium

Complete the code to make the background image fit inside the element without cropping.

CSS

background-size: [1];

Drag options to blanks, or click blank then click option'

Aauto

Bcover

Ccontain

Dinitial

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'cover' which crops the image to fill the element.

Using 'auto' which keeps the original size.

The contain value scales the background image to fit inside the element without cropping.

3fill in blank

hard

Fix the error in the code to set the background size to half the element's width and height.

CSS

background-size: [1];

Drag options to blanks, or click blank then click option'

Aauto

B50%

C50px

Dcover

Attempts:

3 left

💡 Hint

Common Mistakes

Using '50px' which sets a fixed size instead of relative.

Using 'auto' which keeps the original size.

Using 50% sets the background size to half the width and height of the element.

4fill in blank

hard

Fill both blanks to set the background size to 100 pixels wide and 50 pixels tall.

CSS

background-size: [1] [2];

Drag options to blanks, or click blank then click option'

A100px

B50%

C50px

Dauto

Attempts:

3 left

💡 Hint

Common Mistakes

Using percentages instead of pixels for fixed size.

Using 'auto' which keeps original size.

The first value sets the width to 100 pixels, and the second sets the height to 50 pixels.

5fill in blank

hard

Fill all three blanks to set the background size to 80% width, 40% height, and ensure the image does not repeat.

CSS

background-size: [1] [2]; background-repeat: [3];

Drag options to blanks, or click blank then click option'

A80%

B40%

Cno-repeat

Drepeat

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'repeat' which causes the image to tile.

Using pixel units instead of percentages.

The background size is set to 80% width and 40% height, and no-repeat stops the image from repeating.

Practice

1. What does the CSS property background-size: cover; do to a background image?

easy

A. It repeats the image to cover the element area.

B. It stretches the image to fit the element exactly without cropping.

C. It makes the background image fill the entire element, cropping if needed.

D. It fits the whole image inside the element without cropping.

Solution

1. Step 1: Understand cover behavior

   cover scales the background image to fill the entire element area, even if some parts get cropped.

2. Step 2: Compare with other options

   contain fits the whole image inside without cropping, and repeating is controlled by background-repeat.

3. Final Answer:

   It makes the background image fill the entire element, cropping if needed. -> Option C

4. Quick Check:

   cover = fills and crops [OK]

Hint: Remember: cover fills and crops, contain fits fully [OK]

Common Mistakes:

• Confusing cover with contain
• Thinking cover repeats the image
• Assuming cover never crops

2. Which of the following is the correct CSS syntax to make a background image fit inside an element without cropping?

easy

A. background-size: contain;

B. background-size: cover;

C. background-size: fill;

D. background-size: stretch;

Solution

1. Step 1: Identify the property value for fitting without cropping

   contain scales the image to fit inside the element fully without cropping.

2. Step 2: Check other options for correctness

   cover crops, fill and stretch are invalid values for background-size.

3. Final Answer:

   background-size: contain; -> Option A

4. Quick Check:

   contain fits fully without crop [OK]

Hint: Use contain to fit fully, cover to fill and crop [OK]

Common Mistakes:

• Using invalid values like fill or stretch
• Mixing up cover and contain
• Forgetting semicolon in syntax

3. Given this CSS:

div {
  width: 200px;
  height: 100px;
  background-image: url('flower.jpg');
  background-size: contain;
  background-repeat: no-repeat;
  background-position: center;
}

What will the background image look like inside the div?

medium

A. The image will fill the div completely, cropping parts if needed.

B. The whole image will fit inside the div, centered, with possible empty space.

C. The image will repeat to fill the div area.

D. The image will stretch to exactly 200px by 100px, ignoring aspect ratio.

Solution

1. Step 1: Analyze background-size: contain; effect

   This makes the entire image fit inside the div without cropping, preserving aspect ratio.

2. Step 2: Consider other properties

   background-repeat: no-repeat; prevents tiling, and background-position: center; centers the image. So empty space may appear if aspect ratios differ.

3. Final Answer:

   The whole image will fit inside the div, centered, with possible empty space. -> Option B

4. Quick Check:

   contain fits fully, no repeat, centered [OK]

Hint: Contain fits whole image, no repeat means no tiling [OK]

Common Mistakes:

• Assuming contain crops the image
• Thinking image repeats by default
• Confusing stretch with contain

4. This CSS code is intended to make a background image fill the element without repeating, but it doesn't work as expected:

div {
  background-image: url('tree.jpg');
  background-size: 100%;
  background-repeat: no-repeat;
}

What is the problem?

medium

A. background-size: 100%; only sets width, height is auto, so it may not fill the entire element.

B. The URL is missing quotes around the image path.

C. background-repeat must be set to repeat-x to fill horizontally.

D. The property background-size does not accept percentages.

Solution

1. Step 1: Understand background-size: 100%; meaning

   Setting only one value means width is 100% of element, height auto to keep aspect ratio, so it may not fill the entire element.

2. Step 2: Check other options

   URL quotes are optional but recommended, background-repeat: no-repeat; disables tiling correctly, and background-size accepts percentages.

3. Final Answer:

   background-size: 100%; only sets width, height is auto, so it may not fill the entire element. -> Option A

4. Quick Check:

   One value sets width only, height auto [OK]

Hint: Two values needed to set both width and height [OK]

Common Mistakes:

• Using one value thinking it sets both width and height
• Ignoring aspect ratio effects
• Misunderstanding background-repeat options

5. You want a background image to always cover the entire element area on all screen sizes, but never be cropped. Which CSS approach is best?

hard

A. Use background-size: contain; and background-repeat: no-repeat;.

B. Use background-size: cover; and background-position: center;.

C. Use background-size: auto; and background-repeat: repeat;.

D. Use background-size: 100% 100%; to stretch image exactly.

Solution

1. Step 1: Understand the requirement

   The image must always fill the entire element area (no empty space) on all screen sizes without cropping (whole image visible).

2. Step 2: Evaluate options

   contain fits whole image but may leave empty space; cover fills but crops; 100% 100% stretches whole image to exactly fill without cropping or space; auto repeat tiles.

3. Final Answer:

   Use background-size: 100% 100%; to stretch image exactly. -> Option D

4. Quick Check:

   100% 100% fills exactly, no crop [OK]

Hint: 100% 100% stretches to fill exactly, no crop or space [OK]

Common Mistakes:

• Choosing cover which crops
• Choosing contain which leaves space
• Using repeat which tiles