var size=new Array(6);
size[0]="70%";size[1]="80%";size[2]="85%";size[3]="90%";size[4]="95%";size[5]="100%";
var current=0;
function charsize(step){
   if (!document.styleSheets) return;
   if (document.styleSheets[1].cssRules) regles=document.styleSheets[1].cssRules
   else if (document.styleSheets[1].rules) regles = document.styleSheets[1].rules
   else return
   if ( (current+step >=0 ) & (current+step<=5)){ regles[0].style.fontSize =  size[current+step]; current = current+step; }
}