Help refactoring CSS

Answer 1

#adminmenu li.hideshow-news,#adminmenu li.hideshow-users,#adminmenu li.hideshow-pages, li.hideshow-gallery,#adminmenu li.hideshow-references,#adminmenu li.hideshow-settings  {
display: none;
font-size: 11px;
background: #fff;
padding: 3px;}

Answer 2

You should use:

#adminmenu li.hideshow-news, #adminmenuli.hideshow-users, ETC...
{
}

Answer 3

The grouping selector (,) groups complete selectors, not partial ones.

#adminmenu li.hideshow-news, 
#adminmenu li.hideshow-users, 
#adminmenu li.hideshow-pages, 
#adminmenu li.hideshow-gallery, 
#adminmenu li.hideshow-references, 
#adminmenu li.hideshow-settings  { ... }

That said, it might be easier to just say:

#adminmenu li { ... }