css specificity - Overriding a css property -

My HTML is like this:

  & lt; One class = "another adnius" & gt; Add another & lt; / A & gt;   
 I have defined a style in the outer style sheet using this kind of 'other' class.  
  fieldset.associations a.another {color: # 693; Display area; Margin: 7.5px 0px 15px; }   
 I am trying to override the style of the tag using the 'addAnother' class, such as (where necessary):  
  Fieldset.associations a.addAnother {Do not display anything; }   
 But I'm unable to override. Any help is appreciated.  
 Is there any rule that the selector must be the same when overriding a style (I tried to do it, but no use) ??  
 
 
 
 Both properties have the same importance, because both selectors are equally specific. Therefore, if the second appears in the second in CSS then it needs to get more importance to override to reduce it. You can override one before being more specific, like this:  
  field. Association a.addAnother.another {display: none; }   
 or  
  #someID fieldset.associations a.addAnother {display: none; }   
 or  
  Body Fields. Clearing a.addAnother {display: none; }