Change footnote size for html export

doc/userdoc.org

@@ -12,7 +12,7 @@
 #+ATTR_LATEX: :width 4cm
 #+HTML_HEAD_EXTRA: <style> pre.src-pugs:before { content: 'pugs'; } </style>
 #+HTML_HEAD_EXTRA: <style> pre.src-pugs-error:before { content: 'invalid pugs'; } </style>
-#+HTML_HEAD_EXTRA: <style> .remark{ @extend .todo !optional;} </style>
+#+HTML_HEAD_EXTRA: <style> .footref{ color: #2980b9; font-size: 100%; }  </style>
 #+LATEX_CLASS_OPTIONS: [10pt]
 #+LATEX_HEADER: \usepackage[hmargin=2.5cm,vmargin=1.5cm]{geometry}
 #+LATEX_HEADER: \usepackage{ae,lmodern}