Gets or sets the art box: the extent of the page's meaningful content.
public PdfRectangle ArtBox { get; set; }
ISO 32000-2 §7.7.3.3, Table 31, and §14.11.2. Defaults to the crop box; reduced to its intersection with the media box. Setting writes the entry as given (reading reduces it again) and records PDF 1.3 (Table 31). A mutation.