What are the differences between CSS units like px, em, and rem?

What are the differences between CSS units like px, em, and rem?

CSS units like px, em, and rem are used for sizing elements. Pixels (px) are fixed units, while em and rem are relative units. Em is relative to the font size of its parent, and rem is relative to the root font size.

When should I use em instead of rem?

Use em when you want the size to be relative to the parent element, which can be useful for nested components. Use rem for consistent sizing across the entire document, as it scales with the root font size.

Are there any other CSS units I should know about?

Yes, there are several other units like vh (viewport height), vw (viewport width), and percentages (%). Each has its own use cases depending on the layout and design requirements.

Can you give me an example of using these units in a CSS rule?

Sure! Here's an example: font-size: 2em; will make the font size twice the size of its parent, while font-size: 16px; sets it to a fixed size. Using font-size: 1.5rem; will set it to 1.5 times the root font size.