CSS

width css

/*Based on viewport*/
width: 100vh;
width: 100vw;

width css

The width CSS property sets an element's width. By default, 
it sets the width of the content area, but if box-sizing is set 
to border-box, it sets the width of the border area.

width in css

The width property in CSS specifies the width of the element's content area. This “content” area is the portion inside the padding, border, and margin of an element (the box model).