Variable strings : string-set property

Use the string-set property to make a named variable for a string.

The string-set value is pairs of a variable name and followed by the content list stored in the named string. Strings defined with a string-set value can be referenced in running headers.

h1 {
  /*set contents of h1:before and h1 in Chapter content(before) content()*/
  string-set: Chapter content(before) content();