CSS Height: When to Use `100%` vs. `auto`?

Navigating CSS Height Properties: '100%' vs. 'auto'

In a recent interview, you faced a query regarding the distinction between the CSS properties 'height: 100%' and 'height: auto'. Let's delve into the nuances of these properties to clarify their differences:

'height: 100%'

When you set an element's 'height' to 100%, it implies that the element will occupy 100% of its parent container's height. In other words, the element will stretch to fit its parent's height.

'height: auto'

On the contrary, 'height: auto' gives the element the flexibility to adjust its height dynamically. It allows the element to assume a height that accommodates its content. The element's height will automatically adjust based on the height of its child elements, if any.

Here's a visual illustration to further clarify these concepts:

'height: 100%' Example:

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<p>In this example, the 'innerDiv' will have a height equal to the parent div's height, which is 50px.</p>
<p>'height: auto' Example:</p>
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<p>In this example, the 'innerDiv' will have a height of 10px, adapting to the height of its child 'evenInner'.</p>
<p>By employing 'height: 100%', you can ensure that an element fills its parent's height, while 'height: auto' provides flexibility and adjusts the element's height to suit its content or children.</p>
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