One of 25
, 50
, 75
, 100
, "auto"
, or "viewport"
specifying the width of
the tag element.
If 25
, 50
, 75
, 100
, the element's width is a percentage of the
width of the parent element must also be specified.
These percentages do not account for margins or padding and may cause an
element to extend beyond its parent element.
If "auto"
, the element's width is determined by the browser. The
browser will take into account the height, padding, margins, and border of
the tag element's parent to keep the element from extending beyond its
parent.
If "viewport"
, the element's height is determined by the size of the
browser window.