What is a page box in CSS?

You can specify the dimensions, orientation, margins, etc., of a page box within an @page rule. The dimensions of the page box are set with the 'size' property. The dimensions of the page area are the dimensions of the page box minus the margin area.

For example, the following @page rule sets the page box size to 8.5 × 11 inches and creates '2cm' margin on all sides between the page box edge and the page area −

<style>
   <!--
      @page { size:8.5in 11in; margin: 2cm }
   -->
</style>

You can use the margin, margin-top, margin-bottom, margin-left, and margin-right properties within the @page rule to set margins for your page.

Finally, the marks property is used within the @page rule to create crop and registration marks outside the page box on the target sheet. By default, no marks are printed. You may use one or both of the crop and cross keywords to create crop marks and registration marks, respectively, on the target print page.