...
 [%- IF top_menu.$base_name != '' -%]
 [%-   page_title = top_menu.$base_name -%]
 [%-   width = (100/(top_menu.$size)); -%]
 [%-   extra = (100-(width*(top_menu.$size))); -%]
 [%- ELSE -%]
 ...

##</code><code>##

 ...
 [%- IF top_menu.$base_name != '' -%]
 [%-   page_title = top_menu.$base_name -%]
 [%-   width = (100/(top_menu.$size)); -%]
 [%-   extra = ((100-(width*(top_menu.$size)))/2); -%]
 [%- ELSE -%]
 ...

##</code><code>##

file error - parse error - vb-template.tt2 line 31:
unexpected token (/2)
  [% extra = ((100-(width*(top_menu.$size)))/2); %]