Q1. What does opacity do?

opacity sets transparency level from 0 (completely transparent) to 1 (completely opaque).

Q2. How does opacity affect child elements?

opacity affects the entire element including all children - they all become equally transparent.

Q3. What's the difference between opacity and RGBA?

RGBA applies transparency only to the background color, leaving content fully opaque. Opacity affects everything.

Q4. How do you create fade effects with opacity?

Combine opacity with :hover and transitions: opacity: 0.7; transition: opacity 0.3s; hover: opacity: 1;

Q5. What is the default opacity value?

Default is 1 (fully opaque).