CSS CSS Advanced Practice 3

Question 1

What does the CSS custom property fallback syntax var(--x, blue) mean?

Accepted Answer

Use --x, or blue if --x is invalid or undefined

Answer

The second argument is the fallback used when the custom property is not set or invalid.

Question 2

Which property defines how a flex item grows relative to siblings?

Accepted Answer

flex-grow

Answer

flex-grow sets the proportion of available space an item takes when growing.

Question 3

What does 'object-fit: cover' do to a replaced element like an image?

Accepted Answer

Scales to fill the box preserving ratio, cropping overflow

Answer

object-fit: cover fills the content box while preserving aspect ratio, cropping the excess.

Question 4

Which at-rule lets you apply styles based on a container's size rather than the viewport?

Accepted Answer

@container

Answer

@container queries style elements based on the size of their nearest container with containment.

Question 5

What does the ':is()' pseudo-class function provide?

Accepted Answer

A way to match a list of selectors compactly, taking the highest specificity in the list

Answer

:is() matches any selector in its list and takes the specificity of its most specific argument.

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