This property specifies the size and orientation of a page box. The size of a page box may either be "absolute" (fixed size) or "relative" (scalable, i.e., fitting available sheet sizes).

The page box is a rectangular region that contains two areas - the page area and the margin. The page area

<length>  {1,2} | auto | portrait | landscape | inherit

@page {size:auto; margin: 10%;}

@page {  size: 8.5in 11in;  /* width height */ }