tional Emacs modes also supported by the LaTeX listings package */
  pre.src-ada:before { content: 'Ada'; }
  pre.src-asm:before { content: 'Assembler'; }
  pre.src-caml:before { content: 'Caml'; }
  pre.src-delphi:before { content: 'Delphi'; }
  pre.src-html:before { content: 'HTML'; }
  pre.src-idl:before { content: 'IDL'; }
  pre.src-mercury:before { content: 'Mercury'; }
  pre.src-metapost:before { content: 'MetaPost'; }
  pre.src-modula-2:before { content: 'Modula-2'; }
  pre.src-pascal:before { conten