Border Stroke Size

The border-stroke-size parameter allows you to dynamically increase or decrease the thickness of a stroke applied around an image border. It works in conjunction with border-stroke-color to create a visually prominent outline, useful for highlighting images, creating frames, or enhancing design contrast.

This parameter accepts a relative length: a whole number is pixels, and a decimal between 0 and 1 is a fraction of the shorter side of the frame.