Dimensions

The dimensions of a component include its width and height. They should be specified whenever possible. Dimensions do not include margins around an element, but they do include any padding and borders.

Height and width can be specified with minimum and/or maximum values, allowing them to shrink or expand to fit the layout. When describing an element’s dimensions, the width goes first. So, if an element is 12×10px, then it’s 12px wide and 10px high.