Question 1

How to create a circle with border-radius?

Accepted Answer

Set all four border-radius values to half the element's width/height, or simply set 50%, to get a perfect circle.

Question 2

Can border-radius be set for each corner individually?

Accepted Answer

Yes. Use border-top-left-radius, border-top-right-radius, border-bottom-right-radius, and border-bottom-left-radius to control each corner individually.

Question 3

Can border-radius use percentages?

Accepted Answer

Yes, border-radius supports both px and percentages. Percentages are relative to the element's dimensions, so they behave differently at different sizes.